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Addition of a Remote Reservoir to MG TDs and TFs

3 Jan

MG TDs and TFs have a Lockheed brake master cylinder combined with a fluid reservoir. This reservoir has a limited capacity and access to check the brake fluid level and add fluid is difficult in that the cylinder is located just below the floor near to the foot pedals. To gain access the carpet must be folded back and a metal cover, screwed down onto the flooring, must be removed. This gives access to the filler plug through a small hole in the flooring.

Even with the steering wheel removed it is difficult to position one’s head to see down into the opening and pretty well impossible to add fluid and check the fluid level. The only solution appears to be one which involves a mirror, torch and a purpose made dipstick.

Ed’s note: Keith Douglas’ solution was published in the October 2010 issue of TTT 2, available to read here.

The fitting of a remote reservoir addresses both access and potential low fluid levels, eases the bleeding of the brakes, and enables the car user to see any drop in fluid level by simply lifting the bonnet.
The sketch below shows how I installed a remote reservoir to my TF.

The installation was not that easy as access is from above, and this necessitates removal of the seats, steering wheel, drive and transmission cover and the timber floor panel on the driver’s side.

The master cylinder sits in a fairly restricted space between the pedal box and a tubular chassis cross member.

These restrictions were further compounded by the additional supports on the cross member for the 5 speed gearbox fitted onto my car, and I found the best solution involved a banjo off the front of the master cylinder (photos 1 and 2) with a 1⁄4 in feed pipe up (photo 3) to the remote reservoir which I located on the outside face of the tool box under the bonnet (photo 4).


Photos 1 & 2: two views of the cramped space; the banjo fitting off the front of the master cylinder can be clearly seen in both photos.


Photo 3 showing banjo fitting and 1⁄4” feed pipe

Please note that no modifications to the existing master cylinder are required other than the replacement of the filler and cleaning plugs.

However as the work necessitates removal of the master cylinder the owner may take the opportunity to have the cylinder refurbished by a specialist, say Past Parts of Bury St Edmunds, beforehand.


Photo 4 showing position of remote reservoir

MATERIALS USED
Remote reservoir
Single chamber remote reservoir by Girling.
7/16 inch 20 tpi UNF connection.
F 7/16 20 tpi to 1⁄4 inch pipe.
I purchased mine from Europa Spares on the Internet.

Feed pipe
1⁄4 copper pipe of length sufficient to wind down to a location beneath the master cylinder where it is connected to a 1⁄4 inch flexible pipe.

I used standard copper as this is easy to bend using a pipe bending tool.

Flexible pipe and banjo
13 inch long purpose made flexible pipe with a female union at one end to make connection to the 1⁄4 copper feed pipe via a 7/16 inch, 20tpi UNF brake nut and a 1⁄4 BSP banjo and bolt at the other end.

Ideal Hose and Safety Ltd at Rugby made up the flexible hose connected to the banjo and banjo bolt, but no doubt there are others who can do this.

Connection to master cylinder.

Remove the existing drain plug at the front of the master cylinder reservoir. You can drill and tap this to take the banjo bolt but the interfaces must be perfect as brake fluid leaks readily through weak points.

I replaced this plug with one from a Morris Minor restoration company and drilled and tapped this out to take the banjo bolt. Owing to the tight space between the front of the master cylinder and the circular chassis cross member I found it necessary to reduce the thickness of the head of the banjo bolt to enable a fit.

I used standard new copper washers and a big spanner to ensure a tight leak proof fit. In my case the location of the 5 speed gear box connection very much dictated the angle of the banjo.

Existing filler plug. This is a 1&1/8” 20 tpi UNF aluminium plug 3⁄4 inch deep with a vent hole. I tried sealing this but was not assured that it would not leak in time so I replaced this with a solid steel plug from the same Morris Minor restoration company who supplied the other plug. I fitted fibre washers which gave an adequate seal with the new plug well tightened down.

Filling: I left off the new plug from the original filler hole and only put this in at the last moment during filling before the brake fluid spilt over to ensure that there was little or no air trapped in the master cylinder reservoir.

Note: I then made a suitably large opening in the floor above the master cylinder so that I could see the end connections and tighten the bolts if necessary. I covered this with an aluminium plate screwed down to the floor. This being beneath the carpet, it cannot be seen.

Since fitting this system in January 2011 I have found it so useful in not only having the comfort of being able to see the brake fluid level at any time but in bleeding the brakes. It is so simple to top up the remote reservoir during this process.

Additional Note: During the course of this work I discovered that the same Lockheed master cylinder was used on a number of cars in the 50s most notably the Morris Minor. MM specialists often replace the drum brakes at the front with discs and as the reservoir is insufficient they have been fitting a remote reservoir for some time. They use standard 3/16 copper pipe and connect this direct into the predrilled plug they screw into the front of the master cylinder. They have room to do this not having a tubular cross member in the way.

Recently another MG Kilsby member has fitted this system to his TF and in this case used 3/16 copper pipe connected to a flexible pipe and a banjo. I used 1⁄4 inch to ensure I could overcome the air lock during initial filling.

Noel Lahiff

Indicators for a MG TD

5 Nov


Photo 1 showing rear lamp and stainless steel bracket fabricated by Adhoc Engineering along with the replacement inners for the 1130 sidelight on the front.

I love the simplicity of our old T-Type cars but over the last few years I have increasingly felt that sticking my arm out to let other traffic know that I am planning to turn or manoeuvre, was leaving me feeling a little vulnerable. It is fine when the hood is down and the sun shining. Visibility then is excellent but what about when the weather is inclement and the hood and/or side screens are up? When these are in place I find visibility is significantly reduced as well as accessibility to stick out the arm.

My car, like many other MG TDs in the UK, was re-imported from the USA and therefore had an indicator system fitted. However, as it was designed to meet 1950s American regulations it uses the existing white front wing side lights and the red rear brake lights. In short, the brake light doubles as the indicator. The wiring for me as a novice on these things seems complicated with the standard flasher unit wired through an additional relay that controls the indicator by interrupting the brake light if that is in operation.

When I purchased the car this was working correctly but after a year or two something in the system failed and I was unable to trace the problem, so for the last seven or eight years I have happily relied on hand signals. Not seeing any amber indicator lights on the car, the MOT station was content that none were fitted and passed the car every year.

Visiting the MG Restoration Show at Stoneleigh earlier this year I saw that Stafford Vehicle Components had produced a replacement light fitting for T-Types that fits inside the existing wing lamp housing. This fitment offered both white and amber bulbs and seemed like an excellent solution for the front. However there is nothing similar for the rear and looking around at other TD/TFs I found that everyone who had fitted rear indicators lamps had used all kinds of different lights, locations and fitting arrangements.

I decided that I wanted to fit something that was clear, looked period and could if wanted, be fairly easily removed should the car be entered for a Show (not that it ever is!). Also I didn’t want to drill any holes in the car.

The range of lights available on the market is extensive and in the end I went with a chrome torpedo light offered by SVC (+44 (0) 1827 67714) with the view of using the outmost bumper bar bolt as the fixing point. This would allow the lights to be aligned with the central crease in the rear wing and the brake lights.

A local engineering company “Adhoc Engineering” fabricated some stainless steel brackets that would allow easy fitting plus some adjustment to get the alignment just right.

As always, starting one task on an old car inevitably leads to another. On doing a trial run fit on the new rear indicator lights I noticed that the brake lights weren’t working very well and would probably fail the MOT that was due in a few days time. With the help of Brian Rainbow the fault was identified as the inline switch set in the in the hydraulic system. So that had to be replaced first. An easy task but as a precaution I also chose to replace the brake fluid and bleed the system which in turn highlighted a failure of the master cylinder which also required a rebuild or replacement. I digress!

Fitting the front replacement lights was easy following the instructions supplied by SVC. One comment in those instructions was to ensure the front mounting bolt didn’t foul the lower of the two bulbs, which was for the indicator. The first fitting clearly showed the bolt to be marginally too long so rather than pack it with washers I chose to cut off a couple of threads so they fitted perfectly. An additional earth wire was required for each wing lamp and that was easily fixed to the headlamp mounting bracket.

The rear lights were easily mounted thanks to the new brackets and wired through bullet connectors so they could be easily removed if needed. The aim was to use as far as possible the existing wiring loom and Brian had kindly looked at the TD wiring diagram and came up with a set of instructions I could follow.

Both the indicators and brakes lights were wired through a relay located in the passenger foot well. As we had already installed a new brake light power supply wire to by-pass the relay as part of the previous investigation in to the faulty brake lights, this job was already done. The rest was fairly simple and a matter of removing the relay and reconnecting the wiring as per the instructions. Great, it should all work, except it didn’t……

I rechecked the instructions and all the wiring and as all seemed correct so it was time to call in the cavalry. Brian very quickly identified that the flasher relay was dead and I had wired the rear lights back to front assuming the black wire was earth and the coloured one live, which perhaps I should have checked out before fitting the lights.

With a new flasher unit and a quick swop over of the wires in the bullet connectors everything worked perfectly.

Colin Hooper


Photo 2 showing the location of the rear direction indicator lamp.


Photo 3 showing the aesthetically pleasing line of the rear direction indicator lamp in relation to the stop/tail lamp.

Wiring Instructions

Instructions to fit standard direction indicators to an MG TD with stop/flash relay installed.

Note: Wire numbers and colours are taken from the TD/TF workshop manual page N.23 “Wiring diagram for cars with separate control and fuse boxes, headlamp beam warning light, foot operated dip switch and provision for flashing traffic indicator lights”. The one exception is in Step 1 where the previous rewiring of my car has left a connection slightly different to that shown in the workshop manual.

Step 1 – Brake lamps

As these are wired through the Direction Indicator Relay as well and need to work independently of it, they should therefore be re-wired first. I suggest checking the operation of the brake lights before starting work to ensure there are no bulb failures.

1.1 Disconnect the green and purple wire (22) from the Stop Lamp Switch and tape over end of the unused cable.

1.2 Connect a length of new wire (ideally green with purple) from the vacant Brake Lamp Switch terminal to the rear of the car, connecting the end to a new double bullet connector.

1.3 Remove the white with brown wire (15) from the right-hand rear light from its current bullet connector and plug the bullet into the new double bullet connector used in the previous step.

1.4 Remove the white with purple wire (14) from the left-hand rear light from its current bullet connector and plug the bullet into the new double bullet connector used in step 1.2 above.

1.5 Test for the correct operation of the brake lights

Step 2 – Front indicators

2.1 Fit the replacement wing lamp bulb holders from SVC as per the instructions supplied with the units.

2.2 A new earth wire will be needed on each wing lamp as the new bulb holders are mounted in plastic fittings and do not earth though the lamp body to the wing as per the old units. I fitted a short length of black cable to the headlamp bracket bolt although it could probably be fed back to the new bolt retaining the wing lamp.

2.3 Test the side lamp operation (these work independently to the indicators).

Step 3 – Rear indicators

3.1 Fit the lamps as per supplier’s instructions or via your own home made bracket.

Step 4 – Wiring the new rear indicators (see Note)

(Note: in this paragraph the wire colour number is given first and Direction Indicator Relay Unit terminal number second)

4.1 Locate the Direction Indicator Relay Unit. (Mine was in the passenger foot well)

4.2 Label all 8 wires on the Relay (in case the wire colours do not match the workshop manual) with the numbers from the relay, then remove the wires from the relay unit.

4.3 Remove the Relay completely as it is no longer required.

4.4 Connect Relay wires green/red (18 numbered 2), white/purple wire (14 numbered 3) and green/blue wire (20 numbered 4) together using a double bullet connector. (I used a 15amp terminal connector block for this and the next actions and to isolate the unused wires rather than bullet connectors)

4.5 Connect Relay wires green/white (21 numbered 6), white/brown wire (15 numbered 7) and green/yellow wire (19 numbered 8) together using a double bullet connector.

4.6 Tape up Relay wire green/purple (22 numbered 5) as it is not now used.

4.7 Tape up Relay wire green/brown (23 numbered 1) as it is not now used.

4.8 Remove the other end of the green/brown wire (23) from Flasher Unit terminal L & tape it up.

4.9 Identify double bullet connector (17) with 3 green wires and remove the green wire that goes to the indicator switch common (middle) connection. Connect this green wire to the vacant Flasher Unit L terminal.

4.10 Connect left-hand rear indicator lamp to the old white/purple wire (14) bullet connector at n/s rear of car. Ensure that the wire from the indicator light is not earthed to the light body

4.11 Connect right-hand indicator lamp to the old white/brown wire (15) at bullet connector at n/s rear of car. Ensure that the wire from the indicator light is not earthed to the light body

4.12 Test that all indicators are working correctly.

(Option – fit a 12 volt buzzer in place of/or in addition to the Direction Indicator warning lamp as an audible reminder to cancel the indicators)

Ed’s Note: When I fitted direction indicators to my PB earlier this year I purchased the front sidelight conversion from SVC along with a pair of 1130 type lamps with orange lenses for the rear.

My recommendation would be to always fit a buzzer rather than a warning light. I’ve been in the passenger seat of a couple of cars with a warning light and I’ve had to tell the drivers to cancel their indicator switch on more than one occasion.

Original MG T-Series by Anders Ditlev Clausager

7 Jul

First published in 1989 by Bay View Books Limited and re-printed five times. Out of print for some years before Herridge & Sons published this edition in June of this year.

The book needs little introduction, but for those who are not familiar with it, the following reviews give a good flavour of what to expect:

“Page after colourful page of various models in minute detail ….. a must for any owner” Motor Sport.

“Goes a long way to assist the purist in his quest for authenticity…..well written and profusely illustrated” Enjoying MG (MG Owners’ Club monthly magazine).

The cover price of the book is £22.50 but it is available to order from the T-Shop at the discounted price of £18.50. Postage rates are £3.15 UK, £6.60 EU and £12.03 Rest of World. The link to purchase is here: Original MG T Series by Clausager

We do not make any charge for packing, nor do we levy any surcharge for payment via PayPal.

Just good old-fashioned service at the lowest price we can possibly give!

Also back in stock is the MG TD/TF Workshop Manual at £19.50 (compare our price with those of the Car Clubs). Postage rates are £3.15 UK, £5.50 EU, £10 Rest of World.

Supercharging a TD

6 Jul

Colin’s supercharged TD at a show

This article may not appeal to the MG T-Type purist due to the non standard modification I am about to describe, but hopefully it will be of interest to most T-Typers. It is not a detailed technical article but a log of my experiences and thoughts with what I hope are a few helpful suggestions and some worthwhile contacts at the end.

I’d like one of those one day…..!

10 years ago when I set out to buy a T-Type MG the very first car I looked at was a supercharged TC. It was well outside my budget but it triggered a wish to run a supercharged MG at some point in the future. However, as usual when buying a new car, there are all sorts of things that crop up to divert any available funds and it took about another 8 years before I was in a position to start thinking about it again. Even then, looking around, it became clear that finding a supercharger was not going to be easy and made doubly difficult as the project was to be completed on a fairly limited budget. Over the space of the next 18 months I managed to find three for sale in the small ads and two of those were well outside my budget. Not only that, they had been sold by the time I managed to respond to the advert. So rather than relying on the small ads, I started emailing around and talking to other MG owners, as well as some of the T-Type racers.

Careful research bears fruit…..

Eventually I came across Steve Baker’s web site and dropped him an email asking if he had one for sale. To my surprise he did, although it was not the period unit I had set out to get, but a modern Eaton supercharger adapted to fit a XPAG manifold. This unit was a nearly new unit that had been used on his own car, however in a subsequent chat he offered a brand new unit which came with an inlet manifold specifically designed to fit an XPAG engine. It was a new design which had not been fitted to a car in the UK before. A deal was haggled and a date set for nearly four months ahead when I could collect it. This allowed me some time to check the engine over and carry out one or two maintenance items that needed attending to on the car.

Steve was extremely helpful and he guided me on what I should be looking at on the engine to ensure it could cope with the extra power. I was fortunate in that the engine had been professionally rebuilt a few years before I acquired the car and had not covered too much mileage since. A test of the cylinder compression showed that all were within a couple of pounds pressure of each other, which was the major worry. Had there been considerable variation it would have necessitated an overhaul of the engine which was beyond both the time and cash I had for this project. One job that did need doing was to replace the core plugs as three of these had been weeping for a couple of years and they were getting worse. This was a task that I had been putting off as the one in the worst condition was located at the rear of the engine block next to the firewall. The others that needed attention were directly below the exhaust manifold, so almost as difficult to access.

Two steps forward, but one back (later)…..

Like many T-Typers I try and attempt as many tasks on the car myself but, as I am not very mechanically minded, I am not shy about calling for help when my knowledge runs out. Having talked to quite a few people and looked at all the advice in the various journals on replacing the rear core plug, I decided I didn’t want to cut a hole in the fire wall, so the only other solution to make sure the work was done well, was to lift the engine out of the car. A friend with an engine crane kindly offered to help and one sunny late January day with air temperatures hovering around zero we pulled the car on to the driveway and set to the task. I had done as much of the preparatory work myself as I could beforehand, so all we had to focus on was lifting the engine and gearbox out. All went surprisingly smoothly except for one tiny snag. Neither of us remembered to take off the aluminium cover and gear lever from the gear box and it snagged on the firewall as we attempted to lift the block. There was no apparent damage, or so we thought at the time, and once the cover was removed the engine came out cleanly.

Doing the job properly…..

Over the next few weeks the engine was degreased, cleaned of paint, all of the old core plugs removed, the cooling system flushed through before new ones were installed. These were coated with 2 heavy coats of Hammerite paint before being installed. Various gaskets were replaced prior to repainting the engine and gear box in the proper MG engine maroon colour. I also took the opportunity to clean and touch up the engine bay and many of the other peripheral items at the same time.

It was planned that the supercharger would be fed air/fuel via a single 1¾ inch SU carburettor and one of Steve’s recommendations was to improve the delivery of fuel to the supercharger by adding a Facet pump to replace the low pressure unit used on the TD. As I wanted to keep the look of the car as original as possible (the Eaton SC looks very similar to the period Shorrocks unit) I decided to fit a second Lucas pump in tandem with the original to provide the period look of a TDC. Pumps are plentiful but the mounting brackets are not and no one had them in stock or had any idea when they might be available, so in the end I had to have one made.

The really useful Ad Hoc Engineering

A small local engineering firm called Ad Hoc Engineering fabricated one out of stainless steel for me after I provided a drawn design to match as closely as possible the original fitting. Rubber mounts for the bracket, copper fuel line and the fuel tank to pipe connector piece were purchased from Moss. The last item which fits in the fuel tank drain plug was slightly over sized and needed to be machined down, again done by Ad Hoc Engineering. Fitting these items went very smoothly. A hot air paint stripper was used to anneal the copper pipe to ensure it bent easily without fracturing and a honey jar provided a former to obtain nice smooth curves in the pipe. The second line was attached to the chassis rail adjacent to the standard one, using the correct clips. Pleasingly this part of the project went without a hitch.

Remember two steps forward but one back?

One March afternoon my friend came round again we put the engine and gear box back in the car. As he had done this a number of times before he suggested we make sure everything moved freely, by engaging a gear and moving the car back and forth, before putting all the peripherals back on the car. This must have been foresight because however hard we tried we could not engage 1st or 2nd gear. With day light hours still short we still managed to remove both engine and gearbox quite quickly before it got dark. Lifting the lid on the top of the box it quickly became evident that one of the selector rods had been bent when the gear lever snagged on the fire wall.

Mark Sellick to the rescue…..

Obviously this generated another job before the car could run again. Brian Rainbow recommended Mark Sellick as a good person to speak to about gearbox repairs. Luck was with me and he managed to turn around the repair in less than a week and at a reasonable price using a mixture of new and second hand components. It was a good thing I passed this task across because Mark encountered a couple of seized bolts on the top of the selector rods that sheared as he tried to get them out requiring some additional repairs.

Putting the engine back in the car for the second time in the space of a couple of weeks we knew what to expect and this time the unit went in fairly easily. To our joy (and surprise) the car fired up on the first pull of the starter. After all the other components were put back on the car it was run for about 400 miles as I wanted to be sure all was okay before I attempted anything else. All went smoothly so it was onto the next stage of the project.

Following further discussions with Steve he felt that it would be best if we fitted the supercharger together at his work shop, as this would give me confidence on the whole installation process and allow him to see how the new inlet manifold fitted and worked. The 50 mile run up to his house was pleasant in the July sunshine and we decided to do the work on his drive way rather than being inside. Having recently taken the car apart to remove the engine, all the items that needed to be removed to fit the unit came off easily. This included the bonnet, carbs, manifold, horn, radiator, fan and starter switch.

A relatively trouble free fitting session…..

The supercharger came as a kit complete with instructions. It included the blower unit, inlet manifold, double pulley wheel to take the drive belt plus the existing fan belt, clamp bracket for the supercharger’s long nose and a few other peripheral parts like the long V shaped drive belt. The kit was manufactured in the USA and made of duralinium and stainless steel and produced to a very high quality with a superb finish. On the advice of the suppliers of the kit, a 1½ inch SU carburettor was fitted because, as the engine is un-tuned, the fuel demand is not great enough to justify the 1¾ inch carb Steve and I had planned to fit. During the installation a number of small problems were encountered but nothing that couldn’t be overcome fairly easily. Working together at a fairly leisurely pace it took us nearly 8 hours from start to finish to fit the supercharger and get the car running again so I could drive it home.

The TD was booked into Peter Burgess’ workshop in Alfreton, Derbyshire, the following day, to be set up on his rolling road. Steve recommended that I didn’t exceed 3000 rpm until the car had been correctly tuned. So it was quite a frustrating slow drive home that evening and the trip up to Derbyshire the next morning to Peter’s workshop was even worse, having to negotiate the heavy rush hour traffic.

A rolling road experience and 6,500 rpm….!

Until this point I had no idea what to expect when the car was put on the rolling road, having never experienced this before. On Peter’s instructions I drove the car on to the rolling road so the back wheels dropped on to the pair of rollers. He then strapped the back axle down to U bolts set in the workshop floor. The bonnet was removed to give easy access to the engine and he placed a very large electric fan right in front of the radiator to assist with cooling. An electronic metering system was then connected to the engine and a CO2 monitor to the exhaust, so between them the computer could analyse the benefits of any fine tuning Peter would be carrying out. The next bit was seriously scary for me, as he ran the engine up to 6,500rpm, i.e. right off the scale on the rev counter. His comment was that he needed to prove that the engine wouldn’t break half way through the testing. The noise of the car in the confined space of the workshop was unbelievable and was only just louder than my thudding heart!

Over the next couple of hours Peter ran the car like that 12 times, each time up to about 6,000rpm. In between each run he adjusted the carburettor, plugs and timing in order to get the best performance from the engine. With each tweak the performance improved and towards the last test I filmed the dashboard as he revved the car up, to show 6,000 rpm on the rev counter and 100mph on the speedo. If you want to see the film it is on You Tube. Type in “MG TD supercharged”. Please bear in mind that my speedo is probably not too accurate and as there is no wind resistance to encounter in the workshop the car will never achieve this speed on the road.

Afterwards the car was a completely different machine, running ever so sweetly and with noticeably better acceleration and torque. The computer readouts showed that the bhp had increased to 76 at the flywheel, which is excellent as the engine is completely stock and only had 54 bhp when new.

The drive home was completed with a huge smile on my face and a rather heavy right foot!

There were still a few tasks that needed to be completed before the project was finished to my satisfaction. The main one was to source and fit an air filter. I wanted the best I could find and KN was what everyone recommended. After a lot of careful measuring I managed to determine that the narrowest centre mounted version of the pancake type filter would fit but it would require the repositioning of the starter switch further back up the fire wall to create sufficient space and even then it would be a tight fit. It was a fiddly job but it worked and looks good.

So what have been the downsides of supercharging the car?

In fact there have been very few, the main ones being:

• The positioning of the supercharger in the engine bay means that at the moment the car only has one horn. I have yet to find a suitable place to position the second one. It is a small inconvenience to have just one and is more of an aesthetic issue than a practical one.

• To fit the second fuel pump and relocate the starter switch I had to drill four holes in the firewall, two for each unit. These were the only modifications I had to make to the body work. Everything else done to the car is reversible.

• The fuel consumption has increased slightly. More on that later.

So what are the upsides and what is the car like to drive?

Since installing the supercharger last summer I managed to put about 800 miles on the car and these are some of my experiences:

Power: Wow, the car is transformed! The acceleration is better (the car still has the standard back axle ratios) and the car manages to keep up with the modern traffic more easily. But it is the torque that is really noticeable. Hills that used to require 3rd gear are accelerated up with no trouble in 4th, even with a passenger and full luggage rack as we found out when Alison and I went down to the Goodwood Revival last September for a few days away.

Engine temperature: this hardly ever rises above 85 degrees even when being driven hard on warm days and is usually steady around 82.

Starting: The car requires only minimal choke except on cold days when full choke is necessary and then only on the start. If it is left out for more than a few seconds the engine floods and falters.

Fuel consumption: Unfortunately this has dropped to around 23 to 25 mpg (previously 28 to 30) but I think this is as much about a lack of control over my right foot as I enjoy exploiting the extra power. Now that the novelty is starting to wear off I am beginning to drive more normally again so I expect the mpg figure to improve.

Noise: Virtually none extra from the engine bay but the exhaust note sounds slightly louder than before.

Braking: A number of people have asked me what I was planning to do to improve the braking now that the car has the extra power? Interestingly, with the brakes well set up on the TD I have not found the need to make any alterations. Again, from talking to some who use their T-Types for racing and sprinting, many rely on the twin leading shoe of the TD/TF as being the best brakes T-Types ever had. Certainly they cope well with what I ask of the car.

Maintenance: None, as the supercharger is engineered to a very high standard and being a sealed unit requires no additional oil supply or regular maintenance work.

Look: I set out to try and get the period look as far as possible and by and large I think that is what I have managed to achieve, although others may disagree.

Reversibility: I am aware that the changes I have made to the TD are my choice and for my pleasure. The next owner of the car may prefer to return the car to standard format and the work done is all reversible except the four extra holes in the firewall which could be plugged with grommets or filled if necessary.

Reassurance: Having someone else demonstrate that the engine can rev to 6,000 rpm and a little beyond, without breaking, is actually very reassuring and shows the durability of the XPAG. Whilst I don’t run the car to those levels it is comforting to know that the engine is easily capable of running beyond the occasional burst to 5,000rpm that I sometimes take it to.

So what were the learning experiences I can share?

• When taking so much of the car apart, make sure you have made room to store all the components, they take up considerably more space than you might imagine.

• Before starting the work to remove the engine, using the workshop manual make a tick box list of every item that needs to be done, and in the correct order. The same list can be used in reverse for the refitting. This is far easier than having to constantly refer to the book to discover “what next” and saves the manual getting covered in grub.

• Invest in a few packets of sealable sandwich bags and yellow sticky labels, so that everything removed from the car, including nuts and bolts that may be removed from a fitting, are bagged and labelled for easy identification when it comes to replacement.

• Get in a load of boxes to store all the bagged bits you remove. Label and use them logically to make easier the refitting of the components removed.

• Allow at least twice as much time as you think you might need and then add more. Nearly everything takes longer than expected. (Maybe I am too optimistic!)

• When taking the car apart one job inevitably leads to finding another one you had not planned for or costed, so make sure you have some contingency in both the cash budget and timetable for the unforeseen.

• When replacing the cork gasket located under the square steel cover on the waterway at the back of the engine block, do not re-use the 4 cheese head screws but replace them with hex head bolts. With the engine back in place the screws are virtually impossible to access if the gasket hasn’t sealed correctly and weeps. Using bolts allows easy removal of this cover at any time, even with the engine is the car.

• It takes a minimum of two cans of aerosol paint to coat the engine and gear box, preferably three, to get a really good finish

• When removing the twin carburettors, make a timber former to receive them. Using a short length of wood (c.35cm long x 10cm wide), drill 4 holes located to mirror where the carburettor mounting bolts hold them to the inlet manifold. The holes can receive the actual bolts (alternatively, add four protruding dowels to take the place of the bolts to hold the carbs) and use this set up to hold the entire unit securely. This means you can store the carburettors safely without them suffering any alteration to their set up, allowing you to put them back on the car without the need for any fine tuning.

• Take the time to have the car properly set up on a rolling road as it does make a big difference to performance and smooth running of the car.

What next? Back axle ratio change, electronic ignition, five speed gearbox? Perhaps the last item some years down the line when we want to take part in long distance continental touring but until then no changes are planned, as the car is just as I want it. Which begs the $64,000 question “was it all worth it and would you do it again? Absolutely, I love the car set up this way.

I can’t finish this note without saying thanks to those people who helped out this project. Andy Bye for his assistance in removing and replacing the engine and the loan of his engine hoist, Mark Sellick for doing such a good job on the gear box and most of all, Steve Baker for his patience with my endless questions and worries, all of which he was able to answer. Lastly, Alison, my good lady for keeping Andy and I supplied with endless cups of tea, homemade cake and a patient ear when things weren’t going too smoothly.

Colin Hooper, June 2011

Useful contact details:

Steve Baker: www.stevebakermg.co.uk 01865 600251
Mark Sellick: email: louise_and_mark ‘at’ talktalk.net 07733 536966
Ad Hoc Engineering (John Watts): email: john ‘at’ adhoc-engineering.co.uk 01789 731119
Peter Burgess Engineering: www.peter-burgess.com 01773 520021

Ed’s Note: The following table gives the comparative performance figures for unsupercharged and supercharged (Shorrocks blown) TD and is taken from a 1950s article by W. J. Blower.

Above and Below: “Before and After”

Cover Story

11 Apr


TD17904 as found in Zimbabwe

A TD Rebuild was not even on the radar!

I was due to retire at the end of 2008 and was looking for a project to ease myself into retirement. I had been an MG fan for many years, which probably started when I left school and my dad bought me a 1949 MG TC wreck which had to have extensive repairs. From there I graduated to a 1959 Austin Healey Sprite, then marriage, mortgage and kids, which meant I had other more pressing commitments that required my attention and contents of my wallet. By 1995 these commitments were past and I could return to things MG so I purchased a 1965 MGB roadster basket case. Since then I have rebuilt six MGB roadsters so my upcoming project was probably going to be another B roadster, or so I thought.

…until a friend returned from a visit to Zimbabwe with some photos of a TD

A friend had two Frogeye Sprites ex-Zimbabwe that he started rebuilding but had lost interest in; we were in negotiations when another friend returned from a visit to Zimbabwe with pictures of a MG TD that had been standing since 1975. The dilemma was now Frogeyes or TD; with these two on offer my thoughts of another B roadster faded into the distance. Prior to retiring I was responsible for our subsidiary business in Zimbabwe so on my next business trip I went to see the TD. It was parked under a lean to structure where it was left in early 1975 due to an apparent engine seizure, but it was complete and apart from rust was not damaged. The ‘as found’ picture however belies what lay underneath. The TD won the race and I made an offer to purchase it there and then.

Getting the car out of Zimbabwe was the next challenge as it carried a now expired South African licence, but was never registered in Zimbabwe. Speaking to local Customs officials I soon learnt that the Zimbabwe authorities were aware of the value of vintage and classic cars that were being taken out of the country and were consequently confiscating them at the border for the slightest reason, to be sold on auction. The solution was to entrust the removal to the local Zimbabwean who had brought the two Sprites out; money upfront and take my chances was the only business model that could work and it did, the TD was delivered in January 2009.

Assessing the work – taking on a challenge!

With time on my hands I could now do a realistic assessment of my purchase; it was much worse than I anticipated and my first thought was to strip and sell the parts as spares to recover my costs. Fortunately, that thought only lasted a week as my appetite for a challenge took over.

I learnt from the owner that he bought the TD in 1964 in Salisbury and that he had it rebuilt in 1974. He proudly told me that they used Rhodesian Teak (also known as rail sleeper wood) for the tub timbers and that the engine had been overhauled at the same time. He drove the TD for his daily commuting and as a land surveyor he used the car to travel to outlying regions where there were only tracks.

I registered the car with the T Register and found that it left Abingdon on 18 July 1952 and both engine number and chassis numbers were matched and original. The original colour was Ivory with green trim.

The objective was to restore it to its original colour and as close to original as my budget would allow, without taking out a mortgage on the house and this meant doing as much of the work as I could myself.

Any newcomer to a T-Type rebuild is advised to spend time doing internet research on the rebuilding of one of these cars, preferably before buying, as there are many guys out there with a lot more experience that they are willing to share; once committed, find someone who is doing a similar rebuild as original parts are often missing and parts and ideas can be exchanged or borrowed to use as patterns.

Sound advice from Horst Schach

Stripping the car was relatively easy but as each panel was removed more horrors were uncovered. The front quarter panels had rusted through where they abut the mudguards, the front splash pan was irreparably rusted and beyond saving, the RHS front mudguard had rusted away where it joins the splash pan. Apart from the splash pan that had to be renewed all the other panels were saved by welding in new hand shaped sheet metal sections. Horst Schach in his TD restoration book gives good advice when he says not to throw anything away until the job is completed.

The chassis was stripped, sandblasted and primed prior to painting; suspension and steering was overhauled and new tie rod ends fitted. The drive shaft universal joints were renewed and the shaft balanced, the differential was inspected and the pinion bearing and oil seal were renewed. The oval hole wheel rims suffered severe rust damage due to standing in water after the tyres deflated and only two were salvaged. My centre wheel hubs were cut out of the damaged rims and fitted into donor 15 inch rims with new rivets and a generous bead of welding for good measure.

Having stood for 36 years I assumed that all the springs would have lost some of their resistance due to being in compression for so long; this was certainly true of the front suspension, so they were re-tempered and set to their original length, other springs were replaced as assembly proceeded.

Probable explanation for the ‘engine seizure’

The engine was tackled next. The car had apparently been driven and parked but the next day the engine would not turn over and even after trying with a second battery the owner assumed that the engine had seized. I found this rather odd as seizures normally occur whilst driving. Whilst stripping I found that the starter motor bolts were loose and must have been so for some time as it had come out of the bell housing spigot; the starter pinion was out of mesh with the ring gear and the starter motor shaft was bent. This must have jammed up the works and could have been the “engine seizure” that caused the car to be left for 36 years. My elation was short lived however as the pistons were rusted solid in the cylinders. Someone had removed the sparkplugs at some stage and with the cylinders open to the atmosphere rust took over. The engine block was previously bored to +.060” and surprisingly the pistons hardly showed any signs of wear – we did however have to machine the old piston rings out of the grooves. After careful examination and measurement we decided that the pistons were still in good order for further use. The block was re-sleeved back to +.060” and the original pistons with new rings installed. The cylinder head was pressure tested for cracks but found to be OK; the valve seats were refaced but I decided to fit new valves. The crankshaft was crack tested and once again journals were found to be within specification and only new bearings were required. I can only assume that the car had not done many miles between the previous rebuild and the apparent seizure.

End float in the oil pump was excessive so gear ends, body and cover were machined to restore the clearance to specification, a new idler shaft and relief valve springs were fitted.

It pays to examine the big end bolts to see if they have been stretched, I found several that were, so I renewed the entire set. The need for applying special grease or thick oil on the camshaft lobes is well known and essential to prevent wear in the initial start up before the oil pump gets the oil circulating. Lastly, have lots of patience when fitting the rear crankshaft oil sealing cork; I had to do this job twice.

The gearbox looked OK except for the selector forks that were badly worn; these were built up and machined to the correct thickness to fit the grooves in the gears. Selector indent balls and springs were also replaced as were the front and rear oil seals.

The clutch and pressure plate looked in good condition so they were refitted only to be pulled out once the car was road tested due to severe clutch shudder. I had overlooked the damper spring plates between the clutch linings; they too had flattened due to standing. A new clutch plate together with resurfaced and reset pressure plate was fitted and the shudder was cured.

The radiator was never drained during the 36 years and the core had corroded away along with the lower water pipe and part of the thermostat housing, these were all renewed.

Exhilaration and a sense of achievement as the engine roars back to life after 36 years

A highlight at this stage was to refit the engine and gearbox into the chassis and the exhilaration of hearing the engine roar back to life after 36 years. This feeling of achievement gave me new motivation for the remaining challenges.

When doing the body work, the doors must be done first as they are used to ensure the correct positions of the two door posts.

When the previous owner did the rebuild he did not refit the original door locks and striker plates but used residential Yale front door latches, so the front latch pillars were never recessed for the striker plates. If anyone has worked with Rhodesian Teak they will know it is hard, very dense and difficult to cut and not friendly to any type of cutting tool.

Missing tub members were painstakingly fashioned by hand from oak using new sections borrowed from a friend and used as patterns. Assembly of the tub timber is best done once the angle iron frame has been set up and fixed to a pair of trestles as this allows work to be carried out at a comfortable height. All timbers were sealed with a polyurethane preservative.

Using grit blasting to remove old paint and rust is OK on the chassis and other heavy sections but be extremely cautious on thin body sections as the metal will tend to warp due to peening and/or heat build up. I used a number of different paint strippers together with a rotary brush on stubborn paint. Where light rust was encountered, phosphoric acid and a wire brush did the job. To do larger curved areas I covered the area with an old towel then saturated it with the phosphoric acid and finally covered that with plastic sheeting to prevent it from drying out.

Please wear proper personal protection when using these methods and chemicals.

Having stood for so long it was not surprising to find that the bottom of the fuel tank had rusted through and I could not see an easy way to repairing it. I was fortunate enough to find a used replacement with a sound bottom, however the filler neck had been removed so I had to cut out the filler neck from my tank and weld that into this tank.

Once the tub had been skinned it was ready to start the finishing process and at this stage a decision must be taken to either proceed on your own or give it to a specialist. I chose the former and started the process of achieving a smooth flat surface by filling minor dents and undulations. This process took several weeks, miles of abrasive paper, tons of dust and many coats of primer filler. The wife’s vacuum cleaner came in very handy at this stage.

The car had been re-sprayed silver in its previous rebuild but I found that the underside of the toolbox lid was still the original ivory colour and after cleaning and polishing it was used to match the new paint mix.

Mudguards, bonnet and other loose panels were all prepared before any thought was given to applying the top coat. Unlike many European countries there are no laws here preventing the ‘Do-it-yourself(er)’ from spray painting at home; the other advantage was the weather, as most days were windless and above 25° C. There were also days of 35° C but I found this to be too hot as the paint dried too fast. I chose not to use a base coat clear coat system as I did not have the benefit of a spray booth so I used a two pack polyurethane paint in ivory for the top coat and applied several coats. I did not attempt any buffing at this time and left that until the car was fully assembled; this gave plenty of time for the paint to cure.

All 55 items of brightwork had to be re-chromed and it is advisable to do a background search on the company you choose, I chose a company close to where I live who had done good work for other classic car restorers but unbeknown to me they were going through a period of staff problems. Everything had to be done twice and they nearly ruined the radiator surround so do your homework on who you choose.

The front bumper and over riders were rusted beyond repair; both bumpers and the over riders were renewed. The rear luggage rack was also badly rusted but I made a new one and whilst I was at it I also made a badge bar for the front.

The original generator had burnt out but came with the car, unfortunately without the tacho drive gear; this together with the starter had to be rewound, the starter armature shaft was also straightened. A new cotton braided wiring loom was purchased as it does add a bit of originality to the job. Other electrical items that went missing on the way from Zimbabwe were the SU fuel pump, the coil and the Lucas voltage regulator – fortunately used units were readily available from local club members. I decided to convert the front side and tail lights to double up as turn signals. I have yet to find out if they will pass the roadworthiness test as they are not the amber colour.

The ignition/light switch had no key and the Bakelite housing was severely burnt at the headlight terminal but I was fortunate in that a friend had a new switch that did not work, yes a new reject which he gave me. On opening it I found that the blob of solder connecting the incoming power to the rest of the switch terminals had been omitted during manufacture. A blob of solder was all that was needed.

Having stood for such a long time I took all the instruments to a specialist for checking and lubricating. However, during the first 100 yards on the road test both tacho and speedo instrument let out an inhumane screech as they were about to seize. I stopped and disconnected both. The instrument guy got a piece of my mind when I took them back; he agreed to repair them at his cost but told me to check the inner cable length when I refit them. The original steel wound outer and inner cables were in the car when I got it so why would they now be different? I checked the inner cable protrusion at the dashboard end and found that they were indeed too long and when tightening the knurled nut it was putting an axial force on the instrument drive. This was odd but maybe I used a slightly different/shorter route to the dashboard – who knows, but I took his advice and I cut both shorter and had no further trouble.

An unexpected delivery facility

Where it came to the interior this car’s original dashboard had been discarded in favour of a once varnished plywood dash with a centrally mounted radio; the instruments were clustered together in front of the driver. As I wanted to get back to the original I had to find a dash centre panel, not easy to find here where I am. Fortunately there was a guy in Holland who advertised one on eBay UK, we did a deal and he asked if I knew his friend here in South Africa as he was a member of the club. I made contact and to my surprise he was about to leave for Europe and was going to see his friend in Holland, problem solved.

Talking of eBay I was also fortunate enough to get a set of new chromed fuel tank side panels, yes new and still in their wrapping; they were advertised by Moss Europe as shop soiled. I have yet to find the damage that they said it had.

I looked at local upholstery materials as a possible solution for the trim but decided against it as colour and patterns were nowhere near the original plus the hidem trim was just not available. I purchased a full trim kit from Moss. Doing a T-Type for the first time means there are lots of lessons to be learnt; for instance, knowing that the side trim panels go past the floor boards and that the width of the floorboards must therefore be narrower than the actual floor width to allow the panels to pass.

When I purchased the TD the steering wheel consisted of the three spokes, the centre hub and a bare metal outer ring. The outer wheel plastic had long since disintegrated. I decided that a woodrim would be a most appropriate replacement, albeit not original. Once again the internet has several sites giving details of how this is done, so armed with my router and a sheet of 10mm MDF I proceeded to make a wood or is it now an MDF rim for my steering wheel? The final product came out great and coated with a clear urethane sealer – looks like the real thing.

The hood frame that came with the car was cut in half for some reason and the bows were badly rusted. As I had an old hood frame from an unknown car, I was able to use these bows on the TD bits to make up a complete frame. The sidescreen frames were intact but without the chrome trim strips. Having rebuilt six MGBs I had an accumulation of damaged B side moulding strips in stainless steel. The B strips are too wide and of a flatter section but by squeezing them in a vice I was able to create the correct width and half round profile. A small dolly, hammer and bit of heat from a propane torch was all that was needed to create the spoon ends. Being stainless steel they were buffed to look like chrome.

I ordered a new hood and sidscreen covers from a local agent but on arrival I had two vastly different shades of tan which I rejected, this is the problem when importing parts, so I am waiting for a set that match.

The final hurdle here in South Africa is getting the car re-registered as it no longer appears on the department’s computer. There is a system for these situations along with reams of papers, receipts of parts purchased and affidavits to prove it was legally purchased which were submitted in December but to date it is still not approved – yet another lesson in patience. So for now, TD17904 is in the garage waiting for its new licence – that is apart from the regular jaunt it does around the block on a Sunday afternoon.

Randall Everson
reverson(at)mweb.co.za
South Africa
April 2011

MG TD “All Clear” – Redux

9 Mar

Following publication of the above named article in the February issue of TTT 2, the author (Alan Atkins) received a number of expressions of interest from far and wide. Most wanted further information and more photos, so Alan has obliged with some more photos and will be happy to answer any additional queries from interested parties (his e-mail address is alan.atkins903(at)hotmail.co.uk – substitute @ for ‘at’ in the address).

The photos follow:


Practical M.G.TD: Maintenance Update and Innovation

Jonathan Goddard’s book, titled as above, has sold nearly 400 copies worldwide to date. Nearly 100 of these have been purchased from the ttypes.org ‘T-Shop’. In these days of automated everything, ‘T-Shop’ customers receive a personal e-mail, acknowledging their order and telling them that their copy has been dispatched (along with the obligatory automated one!).

The book costs £6.99 with postage costs being £0.81 (UK), £2.25 (EU) and £3.75 (Rest of World). The book can be ordered using the following link: The T-Shop

Postage costs are set to rise steeply from April, but we will hold the pre-tariff increase rates for as long as possible.

TD and TF Rear Axle Oil Seal

8 Mar

There has been some past debate concerning the above subject; it has been said that this is a never ending problem, but why?

The MGTD/TF does not have a flange gasket on its two mating surfaces, which also carries the oil seal in a bearing cap; this cap has to be machined to exact standards in order to control the oil flow, particularly at the two mating flanges which must be absolutely flat (and many are not) – so let us look at some of the reasons.

Firstly, the axle bearing must protrude when fully home exactly ½” from the axle flange; likewise the bearing cap recess for the bearing must also be the same measurement and the tolerance should be -0.000”+0.005”. I know this is technical to some, but it is to ensure minimum movement of the ball bearing race, hence less oil loss and also to the flange mating faces.

Now, the bearing and oil seal cap has a very thin flange and can easily become distorted and damaged on removal and on reassembly, so check before assembly that the flange surface is absolutely flat and free from surface damage; also check with a straight edge of a rule as the flange can be bowed due to the bolts being pulled up unevenly when the cap is tightened down over the bearing. If the cap is bowed then this has to be rectified by machining in a lathe, removing only the minimum amount of metal to achieve a perfectly flat surface. This is a difficult operation to set up in a lathe and is probably best left to a skilled engineer.

Using a dial indicator clock on the lathe to set the bearing cap up, the following format should be adopted; the clock has to be set up at the centre part of the flange, near the bearing recess as this is the only part of the bearing cap which is not damaged and is perfectly flat, so that the clock reads that the surface is truly flat as you turn over the lathe by hand (indicated by the clock hand being stationary on “0”).

The cutting tool used on the lathe should also be set at this point on the bearing cap with a feeler gauge size 2 thousands of an inch between bearing face and cutting tool. Again, turning the lathe by hand, wind out the cutting tool, start up the lathe to remove any metal (which will be very small), finish off by setting the cutting tool at the centre point of the bearing cap so that the cutting tool barely touches the surface; wind out the cutting tool, start the lathe, moving the cutting tool to the centre – you will only be taking off 2 thousandths of an inch of metal and nothing at the centre of the bearing cap. Now you end up with a bearing cap surface which is perfectly flat and the bearing race recess remains correct in depth; you have only machined away the imperfections of the cap surface.

Before you assemble the bearing cap in place you should check the axle collar, on which the oil seal runs, is also perfect (no ridges etc) and is a good fit to the axle shaft (no play). It will also pay you to check the collar angle against the angle on the brake drum (or wire wheel hub if fitting new components). There could be a very slight difference, which has to be rectified because these two angles have got to match and there is no room for error.

What I do is to apply a very small amount of engineer’s blue to one part of the taper cone the complete length of the taper, then insert the cone into the drum or wire wheel hub and rotate with a little pressure back and forwards; remove to see if the blue has transferred on to the drum or wheel hub in a uniform way and for the complete length of the taper.

If this is not the case then what you have to do is to apply a very small amount of fine grinding paste with grease to the cone taper and rotate the cone in the drum or wheel hub taper angle; you will see the dull finish it leaves on the cone angles, which again, must be uniform. Remove all traces of grinding paste from both components, including the slots on the cone body and try again with the engineer’s blue. If the results are good, then all is well. If not, you will need to get out the grinding paste and start all over again!

When you are satisfied that you have got it right you can fix the taper collar in place on the axle shaft, which must be tapped right up to the roller bearing face – this is important. Assembly of the bearing cap with a new oil seal, to which low melting point grease has been added (to the seal internally over the protruding bearing race) is best done with longer bolts, which will then line up all the axle holes correctly. At this point, put around the outer diameter of the ball bearing race an application of RTV sealant and also to the axle flange. Put on the brake back plate, insert the original bolts very tightly and you will see that the sealant is now showing on the bearing flanges, being squeezed out under pressure.

You put a very, very small amount of grease on the taper part of the cone – this is to create a sliding effect on the cone. Place the brake drum or wire wheel hub on the axle shaft and torque the central nut up to 125 to 150 ft lbs (a considerable torque, which will need and extension bar to achieve it). Finally insert the split pin in the castellated nut. Hopefully, it will line up, but more often than not it won’t and you’ll need some thin shims to help.

I have tried to write this technical article in layman’s language – I hope I have succeeded!

Alan Atkins
alan.atkins903(at)hotmail.co.uk

TD Indicator/Sidelight Conversion

2 Mar

I had fitted discreet amber indicator lights under the bumpers on the front of my TD in the interest of safety, but felt that indicators incorporated in the torpedo side lamps would be even more discreet.

Having priced those commercially available I felt that I could make the conversion much cheaper, so I set about finding suitable lampholders and bulbs that could be fitted.

The lampholders I found in Maplins (Stock No. KJ71 @ £1.49 each – four required). The bulbs were from a local motorcycle shop (bayonette fitting 23watt amber [£1.47 ea – two required] and 4watt clear bayonette fitting [49p. each – two required]).

The brackets were made from 3mm (1/8th) flat steel shaped as per diagram (below), with the uprights welded on. I also used two 6mm. nuts and bolts to fix the lamp back to the wing. The nuts were again welded into place to act as captives.

The wiring was soldered to the lamp holders and insulated with ‘shrinkwrap’. The lampholders were attached to the upright with a small BA nut and bolt. The result can be seen in the photograph below.

Altogether a nice little project to work on, during the miserable winter months – and all for under a tenner!

I would advise physically checking the drilling dimensions against your own torpedo lamps before actually drilling. The dimensions I have given applied to mine, which I assume to be original.

Gordon Davies (Wrexham)

Machining the Ovality out of TD/TF Brake Drums

4 Jan

I had a very frustrating couple of years trying to find the cause of a judder transmitted through the brake pedal of my TF.

During the investigation I talked to many “experts” and followed up on several suggestions, one of which was to check the brake drums for ovality – the fronts were fine but the rears had wear ridges and a few thou of ovality. The drums were in good condition and the splines excellent – amazing really on a car some 55 years old. So I decided to machine them back to true as replacements are not available.

The solid rear drums on the TD & TF are driven by the half shafts but locate on the oil seal collar – a split cone that tightens up in a similar way to a collet. To replicate this and to machine the drums concentrically I made a mandrel as shown in the drawing and picture accompanying this article.

The shaft of the mandrel is a sliding fit in the bore of the splines. The split cone is tightened into place through a washer and by a locking nut. This arrangement fixes the drum braking surface parallel to the mandrel. The mandrel and drum are rotated between lathe centres for machining.

To remove the wear ridge and machine out the ovality, I increased the i/d of the drums by 40 thou over the original diameter of 9 inches. The drums are 3/8” thick at the outer rim and reducing this by 20 thou (approximately 0.5%) will not, in my opinion, compromise their mechanical strength.

After machining and using the original brake shoes, the adjusters ran up 18 clicks (out of 20 max.) to lock-up. I solved this issue by having thicker linings bonded to the shoes. This was done by Brake Re-Lining Services, Unit 2, West Point Industrial Estate, Penarth Road, Cardiff, CF11 8JQ. Telephone 029 2070 2900 – contact Richard who is very helpful.

Since asbestos was banned and steel drums and pads are used more-or-less exclusively on modern cars, brake friction materials have become much “harder” and consequently more abrasive when used with the cast iron drums on our cars. Richard recommended using a “softer” woven compound and I have covered several hundred miles with this material fitted to both front and rear shoes. The brakes are very positive and efficient, they bedded in nicely and the rate of wear is not excessive.

The mandrel now sits in my tool box and should anybody wish to borrow it please contact me via email at: keithdouglas1938[‘at’]btinternet.com

Did machining the drums solve the judder? No, but perhaps the rest of the investigation and solution of the problem will be the subject of another article.

Keith Douglas

MG TD, TF & TF1500 – The Essential Buyer’s Guide

4 Jan


Pre-order now from the T-Shop!

Features

• Like having a real marque expert at your side – benefit from 45 years of real ownership (TF1500) experience
• Full coverage of all TD & TF models
• Advice on choosing the right model & condition
• Key checks – how to spot a bad car quickly
• Comprehensive inspection guide
• In depth analysis of strengths & weaknesses
• Discussion of desirable upgrades as well as modifications to avoid
• Market and value data, predicts which models will become collectable
• Details of Club back-up and support organisations

The Author

Barrie Jones is the TF Registrar for the ‘T’ Register of the MG Car Club and he is also its Technical Specialist for the TD/TF models. Barrie has owned his TF1500 since 1966.

Paperback 13.9cm x 19.5 cm 64 pages, 100 colour pictures.

Barrie’s book is not published until 1st February 2011, but you can pre-order your copy now from our website’s T-Shop and it will be sent out to you as soon as the copies arrive from the printers.

Price: £8.49 (£1.50 reduction on price advertised by the Publisher) plus postage (£0.81 UK, £2.25 EU, £3.75 Rest of World). Service excellence comes as standard!