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Restoration of the hand brake cross shaft on the TC

1 Mar

Complete restoration was not the intention until…………..!

The original plan was to remove the hand lever from the cross shaft to have the chrome plating renewed. This would require removing one cable lever by grinding off two welds and removing two taper pins on the driver side end of the shaft. After the hand lever was removed the wear on the shaft where the hand lever is positioned was quite evident. The two brass bearing sleeves in the end supports were also heavily worn and the decision to rebuild the hand brake cross shaft was made.

Making the two brass bearing sleeves for the end supports and the brass bushing for the hand lever would be straight forward since I have a lathe in my shop. What to do with the shaft needed to be decided.

Options for dealing with wear on the shaft

I felt there were two options:

One option would be to weld up the worn area on the shaft and turn it back to size. This would require that the centre hand brake lever be removed from the shaft by machining off the welds and removing two more taper pins since the worn area is adjacent to this lever. I felt it would be difficult to keep the shaft straight due to the welding on a small diameter tube.

Another option would be to replace the shaft but the challenge here was how to locate the three levers back in their correct positions and relationship to each other. Closer examination revealed that the two cable levers and their taper pins that pull the hand brake cables at each end are in alignment with each other. The centre lever that the hand lever attaches to via the threaded rod with the clevis end would require that it be properly positioned so the cable levers would work correctly.

Preparation for making a new shaft

I made a drilling jig that would hold and locate the shaft when drilling the holes for the three levers. The jig consists of two V blocks and clamps for holding the shaft, an end stop to position the shaft axially and a block with a hole and pin that would lock the position of the shaft when drilling the cable levers on each end. I used the old shaft and before I removed the other two levers I needed to locate the pin hole in the pin block. With the shaft in the V blocks and a steel rod in the taper pin holes at the end of the shaft to help measure that the taper pin holes were vertical, I marked the position of the hole in the pin block and drilled the hole. Now that the jig was made it was time to remove the last two levers and make the new shaft.


Picture 1 shows the drilling jig along with all the parts that make up the assembly)

Picture 2 shows the drilling jig after marking and drilling the hole in the pin block to align with the centre hand brake lever

Making the shaft

I bought a piece of tubing that was 1 1/4” OD and 7/8” ID by 24” long so there was enough length to chuck on in the lathe. My first attempt at turning the shaft on my lathe was unsuccessful as I could not hold the OD size consistent over the whole length of the shaft. On the second attempt I left .010” of stock on the OD and took the shaft to work and asked the fellow that runs the cylindrical OD grinder to finish grind the shaft. He had the same problem of holding size over the length of the shaft. At this point I asked myself why I was trying to hold size the entire length of the shaft. It only needed to be on size on each end plus the area under the centre hand brake levers and stop collar. Again I made a shaft leaving grind stock on the critical areas and undercut the other areas by .005/.010”. This time it was successful.

Using the jig was as simple as putting the old shaft without the centre lever in the jig and positioning the jig on the drill press so that the centre lever hole was aligned with the drill and clamping the jig to the drill press table. Removing the old shaft and putting the new shaft in the jig, the hole was drilled thru both sides of the shaft. The old shaft with the centre lever assembled was put back into the jig with the centre lever temporarily pinned in place and the jig was then positioned so that the holes for one of the cable levers aligned with the drill. Take out the old shaft, assemble the centre lever onto the new shaft, pin it in place and drill thru the shaft again. Repeat the process for the other cable lever on the opposite end. The drilled and tapped hole for the stop collar had no relationship to any other holes but needed to be positioned so that the hand lever and the ratchet plate were a nice fit between the centre lever and the stop collar. I assembled these items so the hole could be marked thru the hole in the stop collar.

While everything was apart I had all the hardware zinc plated and the hand lever chrome plated. The only parts replaced were the ratchet and the pawl.

One modification I made to the bushing in the hand lever was to drill a hole that aligned with the thru hole in the hand lever. This allows the knob to be removed at the top of the hand lever and a few drops of oil can be added so that it can drip down to the shaft and provide a bit of lubrication.

The other parts that needed to be made were the bearing sleeves for the end supports. This was just a matter of turning up the sleeves then mounting them on a mandrel to turn the outside shape. The shape is pretty much three flat lengths connected by a generous radius on each side, not really a true spherical shape. The end supports had to have the rivets drilled out, brass sleeves replaced and then assembled with new rivets although a small nut and bolt could have been used.

The assembly is pretty straight forward with putting on the items on the shaft in the correct order. I made new taper pins for the three levers and welded the levers as originally done. The bottom of the hand lever was previously painted so all the needed to be done was a bit of masking and finish painting the shaft. After the paint was dry, the balance of the items were assembled to the shaft.

This was a fun and challenging project. While not everyone has a lathe at home (I really don’t know how I could manage without one) the shaft could be made by a competent machine shop and the remaining work done at home in a modestly equipped shop.

John Libbert Ohio USA

Ed’s note: The following series of photos show the various steps taken to complete the job.

For readers in the UK and Europe, complete handbrake cross-shaft restoration for Triple-M and TA/B/C cars is undertaken by Digby Elliot. He can be contacted on 07836 754034. His address is ‘Beam Ends’. (at Newton crossroads), Southampton Road, Whiteparish, SALISBURY, Wiltshire SP5 2QL, UK.

Digby has just commissioned some hemispherical bushes and end plates for the TA/TB/TC brake cross-shaft and when I spoke to him during the first week in February he said that he hoped to have these ready for inspection at the Stoneleigh MG Spares Day.

He sells the bushes in two sizes (standard and undersize). The reason for this is that he has found from experience that if the old shaft is being re-used it is usually worn on the ends thereby necessitating the use of undersize bushes.


Picture 3 shows the detail of the pin in the pin block and centre hand brake lever

Picture 4 shows using the old shaft to set the drill jig for drilling the first hole for the centre hand brake lever

Picture 5 shows using the old shaft with the centre hand brake lever pinned in place to set the alignment for drilling the first hole for the cable lever

Picture 6 (right) shows the centre hand brake lever on the new shaft in the drill jig just after drilling the hole for the cable lever

Picture 7 shows the new shaft after all holes drilled and two levers pinned and welded in place

Picture 8 shows the final shape of the bearing sleeve for the end supports

Picture 9 shows the mandrel used to turn the outside shape of the bearing sleeves

Picture 10 shows one view of the finished article

Picture 11 shows another view of the finished article

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

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

Replacing T-Type Brake Pipes

14 Nov

The brake pipes on T-Types were originally made from steel and later replacements from copper. No doubt some cars still have their original brake pipes or copper replacements today. Steel pipes are liable to corrosion, of course, and it is now widely recognised that copper pipes have a tendency to fracture over time as a result of metal fatigue. So if you are rebuilding a car or refurbishing your brakes, it makes sense to use the best material available today, which is Cunifer tubing. Cunifer gets its name from the chemical symbols of the metals of which it is an alloy, namely, copper (CU), nickel (NI) and iron (FER).

Cunifer tubing is widely available on both sides of the Atlantic. A Google search will reveal plenty of sources. It is available in 4.8mm, 6.35mm and 8mm diameters. 6.35mm is correct for the TABC, being the metric equivalent of the ¼ inch tubing used originally and 4.8mm is correct for TDs and TFs. It is typically sold in 25 foot lengths, which is ample for a T Type.

Whilst ordering the tubing, it is probably a good idea, (but not essential), to order a new set of nipples. Alternatively, these can be reclaimed from the original brake pipe set. The correct size for TABC is ¼ inch x 7/16 UNF and 3/16 inch x 3/8 BSF for the later cars. 7/16 inch nipples are available with 7/16 or ½ inch AF (across flats) heads. The latter perhaps allow more purchase when tightening. You need 12 nipples for a TABC and 16 for the TD/TF. Whilst ordering material have a close look at the date code printed on your rubber brake hoses. If your hoses are any more than ten years old you may want to consider replacing them at the same time. There are three hoses on T-Types, two at the front and one at the back, but they are not the same across the range of cars. The least expensive source of these flexible hoses is, in my experience, the Octagon Car Club who will sell you a set for little more than some suppliers charge for one! If you live in North America and Octagon won’t sell to you for fear of litigation I can only apologise on their behalf.

If you have a TABC the final item on your shopping list will be the wire to make the armour coils that slip over the tubing to protect them from potential damage in their vulnerable position under the car. Most commercially available brake pipe sets that I have seen for the TABC use wire that is too thin, the turns are spaced too far apart and the coils are never long enough to replicate the original arrangement. All of the pipes on the TABC, except the longest one that connects the three-way union at the front of the car to the flexible hose at the rear, have armour covering. Most are completely encased, and one is encased for part of its length. Fig 1 shows a section of original pipe encased in its armour coil. This is a picture of John James’ TC0750, ‘The Vicar’s Car’, before restoration began. It shows the section of pipe that crosses the brake pedal shaft on the driver’s side of the chassis.


Fig. 1 An original brake pipe and armour coil on ‘The Vicar’s Car’, (complete with 60+ years of accumulated dirt, oil and no doubt some corrosion too).

It took me a long time to find a suitable source of wire to make these armour coils. Stainless steel is the obvious choice to avoid the tendency of plain or plated steel wire to rust, but it needs to be soft enough so that it can be wound easily into the spring-like coils that slip over the pipes. Wire from most sources in the thickness required, 1.2-1.4 mm, (0.048-0.056 inches) is too hard to allow a tight coil to be made using a realistic tension. Eventually I hit on the idea of using ‘tying wire’, which is used in the construction industry to tie reinforcing bars together before they are encased in concrete. I have found this to be ideal. It is sold in two kilogram reels, and comes in a handy cassette dispenser, designed to be worn on a belt around your waist, so leaving both hands free during the winding process.

These cassettes can be bought from the manufacturer Reelfix from their Ebay store: see this link.


Fig. 2 The Reelfix Wire Cassette

I wound coils for my TC using a lathe and a mandrel consisting of a piece of ¼ inch piano wire, about a metre long. If you don’t have a lathe I’m sure your local machine shop will wind the coils for you.

Start by making a means of fixing the wire to the mandrel. This can be as simple as several turns of masking or gaffer tape, or a more elaborate fixture as shown in Fig 3. Fit the mandrel into the lathe chuck, with about 150mm protruding from the chuck, the remainder of the mandrel being inside the headstock as shown in Fig 3.


Fig. 3 Winding the Armour Coils

Now fix the free end of the wire to the mandrel, engage backgear, reverse and the slowest speed. Using a pair of tough leather gloves grip the wire tightly, and turn on the lathe. As the wire is pulled from the cassette keep it under tension and guide it from right to left to form a spring-like coil with adjacent turns touching. When the coil has progressed to within about 10-20mm of the chuck, stop the lathe. Release the chuck, and pull out the next 150mm of the mandrel. If any more than about 150mm of the mandrel is exposed at a time there is a danger that the mandrel will bend due to the tension required to form the coils. Repeat the winding process until you have produced a coil of sufficient length as described in the table on the next page. Beware when cutting the coil from the remainder of the wire in the cassette as the spring will uncoil somewhat as the tension is released. Hold the end of the wire as it is cut and let it unwind slowly to minimise this effect. This slight unwinding is essential to allow the coil to be removed easily from the mandrel and allow it to be fitted over the brake pipe. Fig 4 below shows a length of armour coil taken straight off the mandrel before trimming to length.


Fig. 4 A Length of Armour Coil Ready To Be Trimmed To Length

With a little practice you will be able to produce perfect coils in no time at all. Once you have gained confidence you can increase the lathe speed to quicken up the process. It is a wise precaution to wear safety glasses during this operation, as it is when using any machinery. Make the coils a little longer than specified so that the start and finish can be trimmed off. Keep adjacent turns touching so that the coils can be teased out later as they are fitted to the car. The coils cannot cover the whole length of the pipe with adjacent turns touching because a gap is required at one end of the pipe for the flaring tool to grip it whilst the second flare is formed. This gap is covered by stretching the coil after the second flare is formed and is unnoticeable in practice, except possibly on the shortest pipe on the TABC, which connects the rear three-way union to the driver’s side rear brake cylinder.

Now that you have perfected the production of armour coils it is time to try your hand a pipe flaring. T-Type pipes use double flares, so called because the flare is formed in two separate operations. An example of a double flare is shown in Fig 5 below.


Fig. 5 A Double Flare formed on a piece of ¼ inch tube.

Again it is a good idea to practice on a short length of tube to gain confidence, before making the actual pipes that you will fit to your car. It is not difficult; it is just a matter of gaining confidence, which comes after a couple of attempts.

There are many flaring tools on the market which range in cost from about £25 for a basic tool, up to around £100 for a ‘professional’ version. I have used a model sold by Automec, whose list was included along with Brian Rainbow’s article in August’s TTT 2 (Page 19). The tool is shown in Fig 6 below:


Fig. 6 The Automec Flaring Tool suitable for both 4.8 and 6.35mm tube.

Again, the internet comes in handy here, this time in the form of YouTube:

Above you can watch a video demonstration of one of the many types of double flaring tools. It gives you an idea of how easy it is to make a perfect flare.

Now for some tips – I learnt the hard way:

• When making brake pipes it is a good idea to start with the longest one first. That way, if you make a mess of it, you can cut off the flares and use the remaining tube to make the next longest pipe. If you start with the shortest pipe and make a mess of that, it is scrap.

• Another useful tip is to make absolutely sure you have the armour coil and both pipe nipples (the correct way around) on the tube before you form the final flare. It is not easy to fit either the armour or the second nipple once the second flair has been formed! If you do forget (and I have to admit to doing so myself) again you can cut off one of the flares and use the remaining tube to make the next shortest pipe.

• Note that as a result of forming the flares at each end of a pipe the tube ‘shrinks’ in length by a few millimetres each time. When making your practice flare, measure the length of the tube before and after forming the flare(s) and note how much it has shrunk. Add this amount to each pipe to obtain an accurate finished length.

• Finally, it is important to remove all the burrs from the cut end of the tube; otherwise you won’t get a good flare (see next para for advice on how to do this).

• This is the method I use. Firstly cut the tube to the length specified in the table*, plus a shrinkage allowance determined by the tool you are using (see note above about calculating the shrinkage). Use a fine-toothed junior hacksaw, keeping the cut square to the tube end. Then with the tube horizontal, file the cut end with a fine file to remove the saw marks and the burrs from the cut. Then de-burr the internal wall of the tube with a drill bit.

• Finally suck out any debris left inside the pipe with a vacuum cleaner. This should be done from the end of the tube being worked on, to avoid drawing the debris along the full length of the tube where some of it could remain.

* Table follows.

Table 1: Brake Pipe Lengths for TABC

From – To Finished Length Armour Coil
Front 3-way union to rear hose 1890 mm None
Master cylinder to LH hose 1020 mm Full length
Front 3-way union to RH hose 765 mm Full length
Rear 3-way union to RH rear wheel cylinder union 740 mm 340 mm*
Master cylinder to front 3-way union 740 mm Full length
Rear 3-way union to LH rear wheel cylinder union 395 mm Full length

NB: LH & RH as viewed from the front of the car.

* Only the RH portion of this pipe from the wheel cylinder union to the fixing clip is fitted with an armour coil. The section looping over the differential is unprotected.

Before fitting the armour coils and forming the second flare it can be helpful to form the bends in the end of each pipe that is to be bent around the tightest radius. This is generally the ends of the pipes that connect to the three-way unions or the rear wheel cylinder unions. For really tight bend radii use an external bending spring to stop the pipe collapsing as it is bent. The larger radii can be formed easily by hand after the pipe is complete. This applies particularly to the TABC, which uses the larger diameter tube. The smaller tube used on the TD/TF is much easier to bend as they are fitted. Don’t bend any of the pipes closer than about 100mm to the end before the final nipple is fitted because the nipple will not fit onto a curved pipe. Fig 7 shows an example of a finished pipe with nipples and armour fitted.


Fig. 7 A finished pipe complete with armour and nipples.

Making your own brake pipes is a satisfying job and can be less expensive than buying commercial brake pipe sets, especially if you can borrow or hire a flaring tool. You will know the tube is indeed Cunifer, there is no debris left in the pipe to damage the delicate brake cylinder seals and the coils look just like they did when your car came off the end of the line in Abingdon all those years ago.

Please note: Brake pipes are a safety critical part of the braking system of your car. Do not attempt any work on your braking system unless you are competent to do so. Check for leaks after bleeding the brakes before you use your car on the road. If you are unsure always seek professional advice.

Eric Lembrick
ericlembrick ‘at’ gmail ‘dot’ com

Ed’s Note: Thanks Eric for a really useful article and the links you have given are particularly helpful.

Whilst we are on the subject of brakes there has been some off-line correspondence arising from Brian Rainbow’s article in the August issue (Issue 1). This has centred around the mixing of Glycol (DOT 3, 4, 5.1) and Silicone (DOT 5) brake fluids, and the use of methylated spirits for cleaning the system.

Who better I thought to seek advice than from Barrie Jones, TD/TF Technical Specialist for the ‘T’ Register!

Barrie commented as follows:

“There is a lot of anecdotal evidence that old rubber cups impregnated with DOT3 or DOT4 can swell up if they come into contact with DOT5.  Therefore, it is important to replace them when converting to DOT5.  Even then (according to my friends at Nelson Brovex*), you run the risk of slight swelling.

Five years ago I converted my TF from DOT3 to DOT5 as follows:

1) Flush out the entire system with denatured alcohol (methylated spirits) in order to remove all trace of old brake fluid.

2) Blow out the denatured alcohol with compressed air, leaving the system open to the air for several hours so that any residue can evaporate

3) Strip the entire system down, replacing every rubber component
-Master cylinder cups
-Slave cylinder cups
-Flexible brake hoses

4) Fit a slightly thinner main cup inside the master cylinder

My TF tends to hibernate over the winter, and every spring I had the ritual of `freeing off’ the brakes. Since converting to DOT5 I have never had any problems with corroded pistons. 

It really was `fit and forget’.”

*Brovex Nelson is a supplier of automotive components (including brake hoses and brake cylinder repair kits) based in Camelford, Cornwall.

Ed’s Further Note: If you’ve renewed the brake pipes on your car you will probably have renewed or overhauled the wheel cylinders and master cylinder.

A couple of years back when I was plagued with leaking wheel cylinders on TC0750 and a wheel cylinder repair kit did not do the job, I decided to buy some new bronze ones from C & C parts in The Netherlands. You can also buy them from the MG Octagon Car Club.

The original wheel cylinders were left on the shelf in the garage (never throw anything away!) and it occurred to me that this was really a wasted resource, since if I was to get them refurbished, it might help somebody else. So I boxed them up and sent them to Past Parts in Bury St Edmunds, Suffolk – Telephone: +44 (0) 1284 750729. They arrived back in ‘as new’ condition. Within a matter of weeks an ‘e-mail pen friend’ of mine in Poland needed some for his TC so I was pleased to be able to help.

The service provided by Past Parts was very good and the price for refurbishing four wheel cylinders was £185 which included the postage for getting the cylinders back to me. The postage for sending the cylinders for reconditioning was around £9.

So that’s most things sorted with the notable exception of brake drums. Cast iron brake drums for TA/B/C machined from a modern drum still in production (a Nissan Vanette) can be bought from Brian Thomas of Engineering Solutions in Bexley, Kent. These are the same drums as advertised in Issue 1 (August 2010). Brian’s website can be found at engineeringsolutionsuk.com. Each drum costs £85, which includes an amount for postage. Brian also does VW steering box conversion kits, so he’s a handy chap to know.

Up to now, brake drums for the TD/TF (disc wheels) have been unobtainable. A while back I made some enquiries about getting some produced but there weren’t any manufacturers ‘busting a gut’ to take the job on. I hear that the MG Octagon Car Club are looking to get both TA/B/C and TD/TF drums produced. Those of you who are Octagon members will already know this; those who aren’t will learn of developments through TTT 2.

In the February issue of TTT2 there will be an article about skimming TD/TF brake drums and fitting oversize brake linings.

Simplifying the task of draining and re-filling the brake system

29 Sep

Issue 1 of Totally T-Type 2 included a very useful guide to brake maintenance presented by Brian Rainbow.

I use DOT 4 in my TF and in order to avoid corrosion due to water ingress, I purge and re-fill the system with new fluid each spring.

To simplify the task I’ve designed and made a kit that takes a lot of hassle out of the job and eliminates the risk of spilling brake fluid (which doubles as an excellent paint stripper) onto the chassis.

The pictures and drawing show what the kit looks like and how it’s made.

The procedure is as follows:

Having exposed the master through the floor board, remove the filler plug and attach the reservoir. Now fill the reservoir with clean brake fluid.

Follow Brian’s guide to bleeding the brakes and top up the reservoir as and when necessary. This is easily done because the mouth of the reservoir is wide, it is well clear of the floor board and the fluid level can be seen without the need for a double jointed neck.

Completely purge each slave cylinder – this is still a two-man job.

I find that even after only 12 months the old fluid is cloudy, suggesting the presence of small amounts of water.

Finally to the clever bit:

Insert the length of brake pipe through the reservoir and into the master cylinder – suck out the excess fluid with the aid of a small bore flexible tube and plastic bottle – mine is an old hand cream container.

The length of the brake pipe (see drawing) is measured to leave the brake fluid level in the master cylinder ½” below the neck, as per the Workshop Manual for TD/TF.

Keith Douglas

Editor’s commentary: The photo immediately below shows the early stage of the manufacture of the kit. A brass disc has been silver soldered to the bottom of the length of copper tube to form the base. Under the base is a short length of hexagon bar and the dummy filler cap.

MG T-Type Brake Maintenance

12 Jun

Fault Finding

1. PEDAL TRAVEL EXCESSIVE

(Requires Pumping)

(a)   Brake Shoes require adjusting or re-lining if adjustment is already at a maximum

(b)   Master Cylinder push rod requires adjusting. (Excessive pushrod clearance)

(c)   Master Cylinder requires replenishing

(d)   Leakage past main cup in Master Cylinder

2. PEDAL FEELS SPRINGY

(a) Linings not “bedded-in”

(b) Linings greasy

(c) Linings incorrect type

3. PEDAL FEELS SPONGY

(a) Leakage past main cup in Master Cylinder

(b) Master Cylinder secondary cup worn (Air bubbles rise in supply tank)

(c) Leak at one or more points in system

(d) Brakes not properly bled

4. BRAKES INEFFICIENT

(a) Linings not “bedded-in”

(b) Linings greasy

(c) Linings incorrect type

5. BRAKES DRAG

(a) Shoes over adjusted

(b) Shoe pull-off springs weak or broken

(c) Pedal spring weak or broken

(d) Pedal to push rod adjustment incorrect

(e) Handbrake mechanism seized

(f) Wheel cylinder piston seized

(g) Supply tank overfilled or vent hole in filler cap blocked

(h) Master Cylinder by-pass port blocked

(i) Handbrake cables over adjusted

6. BRAKES REMAIN ON

(a) Shoes over adjusted

(b) Handbrake over adjusted

(c) Pedal to pushrod adjustment incorrect

(d) Master Cylinder and/or wheel cylinder cups swollen, due to contamination with mineral oil
or spurious fluid

7. UNBALANCED BRAKING

(a) Greasy linings

(b) Distorted drums

(c) Front spring broken or loose at anchorage

(d) Tyres unevenly inflated

(e) Brake backplate loose on axle

(f) Worn steering connections

(g) Worn spring shackles

(h) Different grades of linings fitted