Category Archives: Issue 64 (February 2021)

TA/B/C Front brake twin leading shoe (TLS) conversion (continued…..)

Preparing the wheel cylinders. The wheel cylinders that I have chosen to use, are those listed for the Marina 10cwt van or pick-up, being Girling 64678875 (N/S) & 64678876 (O/S), however previously I used the Vauxhall Victor type, which are 64676115/6, sharing the same bodies, which are now looking a bit scarce, both types having 7/8″ bores so are identical in size to those on TD/TFs.

What I have found since starting this build, is that there is yet another alternative, that has both the same bore size & the same fixing hole positions, the only obvious difference being that it has a rectangular boss for the 3/8″ UNF ports, which are 64678928/9, these also have a larger flat mating face around the fixing holes so that a gasket can be employed between the cylinder/backplate but I must stress that I haven’t done any more, than confirm the hole positions/bore size.

I have also found, that pattern cylinders, marketed by both Borg Beck and Quinton Hazell, are freely available, listed as direct replacements, for those listed above first but when enquiring further, are only 3/4″ bore, as they are listed for numerous models of cars so “one size fits all” or not, if you wanted 7/8″?

A modification is required to one of each of the two different handed wheel cylinder ports, as shown, if you want to reuse the original front brake hoses, which is to enlarge the inner port, from 3/8″ UNF, to 7/16″ UNF.

The picture shows how a piece of 3/8″ UNF studding can be used to easily locate a stripped- down wheel cylinder, in a machine vice so that it is mounted vertically, prior to first opening the beginning of the existing hole, to a depth of about one thread, to 7/16″.

Next, drilling the remainder of the hole carefully to the correct tapping drill size for 7/16″ UNF, then without removing the cylinder from the vice, using the chuck to hold the taps, the threads can be tapped by hand or to simply start the tap off squarely.

The two copper link pipes are 3/16” diameter, being formed from lengths cut to 13.25″ so as to get tight to the bottom mounting bolts and out of harm’s way.

The bleed nipples are stainless, being fitted into the front ports and are really easy to bleed, due to the layout of the cylinders, being one in front of the other, instead one above the other, I suppose that bleeding would be even quicker, were you to jack the front of the car up, more than just getting the tyres clear of the ground?

Fitting the wheel cylinders. Because of the significant differences between the TC and Marina backplates, 5mm thick mild steel spacers are required to place the centreline of the wheel cylinders correctly in-line with the brake shoes.

The pictures show that they are a simple spacer but the area shown within the red circle, requires a significant chamfer to be created; this is to allow the end of the brake return springs to move sufficiently, to allow the spring to rest, when the shoes are centralised, without any side loading.

Easier to do this now, than to have to do it later, as I did, with a mini grinder!

These spacers only require a light weld along each end and when they are attached, just leaving the return spring mounting plates to be fitted.

Unfortunately, you will once again need to check the plates for flatness and most importantly, that they have not dished because the cylinders need to be perpendicular to the drum face so out with the straight edge, then perhaps back to the press?

Modifying the brake shoes.

The brake shoes employed on this conversion, are those used on three vehicles, manufactured in the same time frame, the most exotic being the Morris Marina 10cwt van or pick-up, then the Triumph Toledo 1300 and lastly the Vauxhall Victor. They all used 9″ diameter Girling brakes so their diameter is compatible with the first 3 models of T-Type, having only S.L.S. brakes.

New old stock shoes are available at the moment, for varying prices but by now their linings will be a little on the hard side, not to mention containing the dreaded “A” word so the first thing to do, is to go outside, hold the linings over one of the many holes in the top of your trusty B & D workmate, then using a punch, remove the rivets by punching them out through the linings, then please be responsible about disposing of the 4 old linings.

The existing adjuster pegs need to be then removed so a bit of sawing, drilling & punching, then with the use of either a lathe, milling machine or a pair of odd leg calipers and a hacksaw/file, carefully remove 1/8″ from each edge of the shoes because they are 1/4″ wider than is required, as can be seen in the pictures of before, then after.

On the trailing edge of each shoe, I decided to fit 1″ square packers, made from 16 swg stainless steel but mild steel or brass should be fine, these are attached simply using 1/8″ aluminium pop rivets but to make a neater job, I countersunk the back 16swg plate’s 2 holes, to allow the rivet to spread into it, then allowing me to flatten it into the countersink, leaving it looking similar to its head.

I marked out 4 plates first so that the holes would be away from the guide slot in the back of the wheel cylinders, first drilling them just under 1/8″, then carefully clamped the 3 layer sandwich together, with some long nosed mole grips, before drilling each assembly individually 1/8″ and riveting them so as to avoid mixing up any of the parts.

When the plates are attached, I filed them to match the radiused profile on the end of the shoes, then filed a shallow chamfer up the sides of these curved edges, to allow the sandwich to move freely in their slots in the back of the cylinders, giving them the ability to rock a little, both up and down, to aid correct alignment of the shoes with the drums.

The original Marina brake plate had them sitting on a ledge, only allowing them to move into the drum, against the hold down springs but I wanted it to float a bit more than that.

The piston end of the shoe is guided by one of the original triangular guide plates, as previously removed, rewelded into a new position so the shoe sits centrally, as originally intended but can pivot both ways a bit, against its central hold down springs.

The new adjuster pegs/pins are simply cut down stainless steel M8 bolts, nuts and washers, as shown, luckily in the 2 bottom shoes, they make use of an already existing hole from the previous peg but on the top shoes this is not the case because this area on the backplate is not flat, which is what the new adjuster requires.

The position for the top shoe adjuster pegs can be determined by first fitting that shoe, with its return spring to the modified back plate, along with the lower shoe the same, then by having the brake plate uppermost, under a bench drill or mill, first making sure by rule measurement, that the shoe is seated centrally with the edge of the back plate, the either 3/8″ or 2.5mm hole, for the adjuster cam, needs to be carefully spotted through, onto the brake shoe.

This is safest perhaps being done by rotating the chuck with just your hand, in the reverse direction, as you only require it to mark the centre position of the hole, then with the shoe removed so that the mark is visible, the position for the new adjuster peg/pin, needs to be 11.5mm towards the lining, from the mark left by the drill, this should then only hold the shoe off of the bottomed cylinder by about 0.5mm, hopefully ensuring that the finished assembly will easily enter the drum, even if a brand new one, with plenty of adjustment remaining.

After previously having used a woven lining material, that works well on steel motorcycle brake drums, I found their annoying squealing noise, when just feathering the brakes so bad, that I switched lining materials to the type recommended by Frans Sitton, being Ferodo DS3920, which is a great improvement, being done this time for me by Villiers Services, who despite what is going on with Covid, turned them around in a respectable time and were reasonably priced too.

As standard, DS3920 comes in a 5mm thickness so is ideal for slightly worn drums, being only about 0.2mm or 8 thou oversize, it is a soft material, of a greenish colour so easy to file some nice gentle chamfers on, giving you a nice progressive feeling.

Brake Shoe Adjusters, Hold Down Pin Assemblies & Return Springs. The modified brake shoes employed on this conversion, were retained by hold down pins, passing through short slots, about midway along the steel shoe, these slots are reused, without any modification required but had previously used different length pins, as well as different springs to those now used. The amount of work to get everything to fit, depends on the gauge of pin acquired, as I have only just discovered because 42mm long pins, suitable for use on Fords, can be supplied as either a heavy gauge pin, with a 9mm diameter head or one which is lighter gauge, with an 8mm head, the latter will avoid some fiddly filing, as mine were the heavy ones.

In the picture of the hold down pin components,  the coil springs are I believe for British Leyland, being 14.5mm in diameter by 22.5mm long, at each end of these springs are “Girling Type” hold down washers, which if you have the better pins, will not require slight modification, with a needle file, the spring clips, that hold it all together, are for Fords, either Fiestas or MK5 Escorts, maybe others as well, these will require squeezing down a bit, as shown, then the whole lot goes together OK.

The brake shoe return springs used, are the type employed on the 3 original vehicles concerned, being Girling SS2.

Adjusters are however a complete “foreigner”, in more ways than one, being intended for use on “Willys Jeeps” but readily available, as pattern parts. What I have chosen to do with them, is to not use the nuts & spring washers, as supplied but to substitute stainless steel nyloc nuts, with Dowty washers.

This has 2 advantages, the first being that it enables the area of thread within the nuts to be sealed so if copper grease is used, it should always come undone – but I also found through use, that the Dowty washers act like a friction washer, enabling the adjuster to be rotated, then staying in position, in a similar way to the original adjusters, making their use a very simple affair, just needing a tiny spanner by comparison to the original brake.

The last few ‘fiddly bits’. These are quite fiddly bits to make and fit, the return spring plates but very important to get right, easy with a milling machine, otherwise some careful sawing & filing required, with maybe a little bit of mini grinding to finish off.

As with much of this, it needs to end up right, fitting well, my first attempt was not good enough, as it needs to fit closely around the shoulder of the wheel cylinder mounting points, to give enough metal around the area for the return spring holes to go, you can improve this slightly by only marking the position for these holes with the jig.

When marked, carefully eye things up and like me you should be able to move the hole positions over a millimetre or so, gaining some more metal where needed around the holes.

When drilled, you will need either to be patient with a rat tail needle file or use a mini grinder, to chamfer the hole, as required on one side only at the top and on the opposite side to that below because the spring needs to be seated horizontally to be parallel with the bracket, allowing the shoes to sit down on the guide plate, at the piston end of the shoe, before even the hold down pins are fitted.

Also as previously mentioned, the return springs need to swing across, slightly past the position required when the shoes are centred, to ensure there are no side loads, causing any bias to the shoe position, when the shoes retract.

That is how you get it to be a “floating” brake shoe, with a bit of patience so why rush, when if you take the time now, you can more confidently rush later!

The finished job.

Ed’s note: A couple of updates from Steve Priston as follows:

There is actually a fourth popular model of car that employed the same nine-inch brake shoes, making them even more plentiful. This is the MK1 Cortina Super, from the 1200s up. Also, EBC make the required shoes new, at about £35, part number EBC6235, so sustainable for a good while but original NOS shoes are a lot cheaper!

If anybody is seriously interested in tackling this conversion a paper copy of the template can be made available for a modest cost, as well as many more pictures.

There are, also, some laser cut blanking discs available for the hole left by the original wheel cylinders and arrangements could be made for some more infill plates to be folded-up locally as long as his costs are covered.

Steve Priston has collected some of the required components, for his future use, whilst they are still plentiful and relatively cheap, as he is intending to make one more set. Whilst he is not in position to actually manufacture currently, due to an impending house move, he would be willing to source kits of parts for those who might prefer it or could pass on the relevant eBay/part numbers.

Steve is willing to share his knowledge and experience gained in the manufacture of this TLS conversion. He can be contacted at: steve.priston(at)virgin.net [Please substitute @ for (at)].

Lost & Found

TC4526

Well, not really Lost and Found, but certainly lost as a complete car. It is (was) TC4526, a CKD car assembled in Ireland. Unfortunately, the garage that the car was in caught fire, caused by a faulty battery conditioner. It destroyed 4 cars and a horse van.

Thanks go to Stewart Penfound for drawing this to my attention and for sending a couple of pictures and to Steve Baker, who sent this picture.

TA2836 (JRE 932) – an automatic TA

This car was featured in Issue 33. The car had been converted to automatic transmission using a Morris Marina engine and gearbox. The conversion was done by Andy Schultz of Cuerden Classics in Preston for an owner who had suffered a leg amputation. This enabled the owner to continue to enjoy driving his car for a short while, but unfortunately, he died soon after and the car was sold by Andy, along with a TA engine and gearbox. Andy did not keep the details of the new owner; all that he can remember is that the car went to a new owner in the south of England.

I’d be grateful if the present owner would get in touch with me as we have a potential buyer for the Marina drivetrain if she/he wants to sell it.

jj(at)ttypes.org [substitute @ for (at)].

TA registration number DKT 634

Kevin Morrison in Cyprus, who is well on with the restoration of his TC, finds it hard to believe that he used his TA on a daily basis 50 years ago, doing many thousands of miles in her, even driving up to London in the early ‘70s.  He’s just discovered that it was an ex-Kent police car and he thinks it still exists, having been exported to Germany in the late 1980s.

It would be nice if the present owner could get in touch with me jj(at)ttypes.org [substitute @ for (at)].

1949 TC7891(HAA 308)

Mention was made of this car in the last issue. Liz Moore, daughter of a former owner has now sent me a photo and has written some notes entitled “Looking for HAA 308”

“My father owned this MG TC in the late 1950s and early ‘60s. According to family legend, it was his first car; that must have been a worry for my grandmother as he was still a young driver. HAA 308 was first registered in 1949, body colour British racing green, which Dad loved. Unfortunately, that was never an option for a family car in the 70s, when Dad had to ferry 4 small kids around!

Sadly, my father died young in 1990. Recently, I “inherited” several boxes of family photos and documents. During lockdown, I have had time to sort through everything, and found a good picture of Dad with his beloved MG (on left in the photo). This photo is from the Wiltshire Times newspaper; it must have been a car rally, but I cannot be sure of the date. The gentleman in the middle was my father’s best friend at the time, with his girlfriend sitting on the bonnet of his own MG TC. (I cannot imagine my father allowing any girl to sit on the bonnet like that!) Curious about the car, I searched DVLA and found that HAA 308 is still taxed and on the road somewhere in the UK.

I would love to get in touch with the current owner and learn more about this car. My siblings have other photos, I am planning to get these digitized. I can be contacted on haa308(at)outlook.com

TA0943 (DDH 900)

Cathelijne Spoelstra would like to contact the present owner as she thinks that there may have been a Dutch connection in the past. If you can help, please get in touch with Cat at info(at)mgworkshop.nl

Bits & Pieces

Sheet metal work

Andrew Carnan reports as follows:

“BK Sheet Metal Ltd have recently remade the roots of both of my front TC wings, removed dents, reinforced cracked areas and straightened them along with repair work to my running boards. I can thoroughly recommend their quick work and excellent workmanship, and they are right next door to the MG Octagon Car Club.  Contact Jason Lee at BK Sheet Metal Ltd, Sparkenhoe House, Southfield Road, Hinkley, Leics. LE10 1UB. Tel. 01455 633511 info(at)bksheetmetal.co.uk [substitute @ for (at)] www.bksheetmetal.co.uk

 It is difficult to find good panel beaters that have T-Type panel experience”.

“I also can recommend SPL Ltd at Dudley who stripped all paint and rust prior to sheet metal work and afterwards e-coated all panels in primer. See their website at www.surfaceprocessing.co.uk I have tried cleaning bodywork in the past with wire brushes, also blasting, using various media but the acid based total immersion processes at SPL and the subsequent electrophoretic tank priming is almost unique and incomparably better”.

The Kithead Trust https://kitheadtrust.org.uk/ is a useful reference website if you want to find out where your car was registered from new and with contact details for the Licensing Authority who first registered it, together with an indication of what records they still hold. Before you get too excited, surviving records are few and far between, as most will have been destroyed when the vehicle licensing work was centralised with the setting up of the DVLA (Driver and Vehicle Licensing Agency for the benefit of readers outside of the UK).

The Kithead Trust was the recipient of some of these records. In the main these consisted of index cards, the function of which was recently described to me by the ever-helpful Peter Jacques of the Trust as follows:

The index cards we hold were originally location cards.  Every vehicle had a vehicle file which followed the vehicle around according to where it was currently owned.   The card system recorded any changes of location by way of a request from the new area to the previous area to forward the file.  Consequently, a new card replaced the old which was discarded.    The cards themselves never included ownership details; after all, the vehicle file itself could be referred to in case of need.    The system lasted until computerization in the 1970s.

Having read this explanation, it does seem to me to have been a wonderfully bureaucratic process with files whizzing around and criss-crossing the country; so much so that one is almost grateful that the DVLA was established – but no, hold your horses! – based on my experience of many dealings with this organisation, I hesitate to endorse this sentiment!

TC rear spring shackles

Paul Busby was short of two of these, so he made a small batch. pyb.7(at)tiscali.co.uk [please substitute @ for (at)].

TD & TF rear springs

I have never seen a drawing for TD or TF rear  springs, but the two spring makers I am aware of (Jones Springs in Darlaston, West Midlands and Owen Springs in Rotherham, South Yorkshire) must have them as they supply the springs.

However, to the best of my knowledge (it is certainly the case with Jones), neither of these companies bore the springs for the insertion of the interleaf pads and do not supply the springs with the wider clips to accommodate the angle pads.

First two pics show the angle pads in position; the next one shows the wider angle clips.

This begs the question as to why the drawing does not show the holes for the interleaf pads and the (wider) measurement for the spring clips, or if it does, why the springs are not made to the original specification.

However, we are where we are, but I wanted my springs made to the original spec. So, to cut a long story short, I agreed with the helpful Kevin at Jones Springs that I would remove the rivets from my old springs to free up the clips and them on to him. Kevin suggested that I also send my interleaf pads for him to insert between the leafs (I refuse to refer to them as leaves) which would save me taking the new springs apart.

By the time this issue of TTT 2 appears I am hoping to have received my new springs.

Expansion core plugs –        The following from Michael Bangs:

“A leaking large core plug at the rear of the XPAG block has been a problem that has led to owners mutilating the bodywork in an effort to fit a replacement.

There is no room to flatten a replacement core plug with a hammer. Short of lifting the engine and moving it forward, there seemed to be no obvious solution.

Faced with this problem on my TC, I investigated various websites and found an answer on the mgaguru website (mgaguru.com).

MGAs have a similar access problem and a metal screw in core plug made by Dorman is identified as the answer. The size wasn’t right for the TC but I found a screw in plug on eBay that I thought would do the job.

It uses rubber sandwiched between two metal plates. When the plates are screwed together, the rubber expands to form a seal.

These expansion plugs seem to be available only in the USA. I ordered some and they work (Item 222794860473 on the eBay US site).

They are intended to be a temporary fix, but on a You Tube site someone demonstrating them said he had used one for five years!”

TF heat shields

I have a few of these, designed by Barrie Jones in stainless steel. The top picture is the TF shield, the bottom is for TB/TC which should be available in about one month (just waiting for the spacers).

The heatshield will not fit if you have a 5-speed ‘box and the engine has been moved forward.

The price of the TF shields is £19.50 each plus postage. The cost of sending the shields from 1st January 2021 within the UK is £3.20. Unfortunately, the cost of sending outside of the UK has risen dramatically with three price increases during the last 12 months and it is best to contact me for a quote: jj(at)ttypes.org [substitute @ for (at)].

Starter motor and dynamo overhauls

Philipp Will in Germany e-mailed to say that he is very pleased with the quality of the work done for him by Chris Wallis on the restoration of his dynamo and starter motor. In particular he’s most impressed with the speed of the turnaround and very good communication from Chris.

Chris Wallis, 39 School Lane, Chellaston, DERBY DE73 6TF (01332 703630) clwallis39(at)hotmail.co.uk [substitute @ for (at)].

Luvax TA/TB shock absorbers – Wanted

Tom Lange in the US is seeking a set of 4, pair or single Luvax TA/TB vane-type shock absorbers needed for TB0327.  All help greatly appreciated. tlange(at)prexar.com [please substitute @ for (at)]

TC PARTS

Now that I have sold my TC, I have a few surplus parts that I no longer need. These are as follows:

  • (new) keyed washers for the front ‘pin’ on the TC rear leaf spring (5 available at £4 each plus postage at cost – I am not sure if these are available commercially).
  • (new) oil seals for the bottom of the Bishops Cam sector shaft housing (3 available at £4 each plus postage at cost).
  • Buffer rear axle (Moss UK part no.280-660) unused, but old – free, please pay postage.

Thin steel gaskets for tappet chest cover

Further to Paul Ireland’s Keeping Oil in an XPAG article in Issue 63 ((December 2020) sufficient interest has been shown for the thin steel gaskets, so an order has been placed for 10.

The gasket material to use with this installation is automotive cork (nitrile bonded cork).

Enquiries for the thin steel gaskets (and for the previous TC PARTS item to jj(at)ttypes.org [please substitute @ for (at)]

TA/B/C Front brake twin leading shoe (TLS) conversion

Issue 55 featured an article by Steve Priston about a TLS conversion he did on his TC, using a backplate from a Morris Marina 10cwt van as a pattern for altering his TC backplates. The article raised not a whisper, so Steve, having done the job a second time (this time for Trad Harrison), thought he would explain in more detail the various processes to encourage other brave souls who might be contemplating the task.

Over to Steve………

The job can be broken down into the following tasks:

  • Stripping the original back plates of the unwanted parts
  • Modifying the back plates (some ‘surgery’ required)
  • Making pieces to fill the holes in the back plates
  • Welding to fill the holes (akin to ‘sewing the patient up after surgery’)
  • Cleaning-up after welding & straightening, due to the distortion
  • Using a template for the first holes to be drilled into the backplates.
  • Preparing the wheel cylinders.
  • Modifying the brake shoes
  • The revised return spring plates, along with those little triangular guide plates, including the last bit of welding.
  • Ensuring that the return springs are able to let the shoes move adequately.
  • Positioning the adjuster peg/pins on the shoes
  • Final assembly

Stripping

Modifying

Cutting out the ‘bulge’ at the bottom of the backplate to enable the lower brake shoes to fit.

Making pieces to fill the holes

These pieces to fill the gap where the bulge has been cut out and to be welded in, along with the circular pieces.

Cleaning-up after welding & straightening, due to the distortion.

I didn’t take any pictures of the actual straightening but this is how it was done. Firstly, I found a small circular steel blanking flange, which when it had 2 opposite edges cut back, then sat nicely into the recess, in the centre of the backplate, along with a second unmodified flange of a similar size.

Then I found another much larger steel blanking flange, to act as a flat base plate, under the hydraulic press, larger in diameter than the backplate; but any heavy enough plate, larger than the backplate will do.

Now the Work’s press, has a pair of parallel supports so with the ‘bananafied’ plate the right way up, to ;de-banana’ it, the cutdown little flange, was put into the recess, for the press to push against and the plate was very carefully adjusted, probably only showing a 2 or 3 tons of pressure so even a small press in someone’s shed or garage would do it.

The next stage, was to lay the large flange onto the parallels, with the plain small flange under the centre offset portion of the backplate, then the cutdown flange was dropped into the recess, with the press then used, simply as a clamp on top.

So out with a steel rule, to measure the variations between the rim and the plate below, time to realise that the offset should have been carefully measured before welding but I did have 2 original plates so, “be warned”, measure the original offset of the backplate before getting it welded, if you want to be really careful!

You can however, when measuring what is before you, determine what you should be aiming for, as a gap measurement, then with that naughty number 2 Thor mallet, that you frighten those spinners off with, instead of using the next size down, use it to adjust the rim of the back plate, remembering that you want the area between the rim and the centre recess, to be parallel with the flat plate below, as well as getting the gap between the rim even, with the lower plate.

I didn’t require anything else to get it flat again but you will need to revisit the press, after stage 2 of welding.

Using a template for the first holes to be drilled into the backplates.

Imade a cardboard template, combining the centre hole, with the four 3/8″ diameter mounting hole positions, of the MG TC backplate, along with the required geometry, from the Morris Marina 10cwt van backplate, that I had previously used, but needed to somehow easily create a drilling jig from it.

The jig needed to be made by the person in possession of a single sheet of A4 paper, with the hole centres printed on it, this I have managed to do, if you look at the sheet of paper, marked in pen and highlighter.

I wanted a readily obtainable material, that was easy to work with, for the drilling jig, not initially realising the advantages of my first choice, which was clear perspex, something that can be purchased, cut to A4 size, in various thicknesses.

So, I obtained some 6mm thick clear perspex sheet, cutting it into two A4 pieces but as I wanted to create a “master” template, I asked my friend, with a nice milling machine in his home workshop, to align a 2.5mm drill, with each of the marked hole centres on the paper template, drilling through both paper then perspex below.

What Mike, my welder friend and very clever model engineer said, was that he thought simply using a centre punch, through the paper, indenting the perspex below, would probably be good enough, to then pick-up the hole positions OK for what was intended.

But what he produced for me with his mill, also gave me a working template/drilling jig, hence the 2 sheets of perspex, the reason for choosing only 2.5mm, as a drill size was because with a 0.5mm propelling pencil, it could be used as an accurate stencil, producing just a dot on the paper, also drilling such a small hole through both perspex and 10 gauge mild steel, is very easy.

The first thing to do with the perspex jig, was to open up the 4 mounting holes to 3/8″, by first using a centre drill, then a twist drill, as shown.

Then using these first holes, the jig was attached to the backplate as shown, with the perspex being spaced away from the backplate by a single plain washer, at each hole, in an effort to keep the plastic as flat as possible.

One thing I must now point out, is that the remaining holes in the jig/template, must stay at only 2.5mm and that the first upward face of the jig to be used, must be marked as “SIDE 1“, as must the plate that it is used on, when orientated this way.

The other side must be marked as “SIDE 2”, to avoid any confusion because the layout of the twin leading shoe brake, has to be “handed”, for it to work and by simply turning over the jig, you obtain the opposite hand so clear markings must be made, to avoid any mistakes.

I only used the very basic drill shown (see next but one pic) because I could lift it outside for pictures, then with a piece of board attached to it, the plates fitted OK. The most important things to consider when using the jig, is to make sure that the drill is perpendicular to the job, that the hole in the plastic is lubricated, that the job is not clamped to the drill table and that before the drill is under power, that it is free to move vertically in the hole of the jig, to preserve the accuracy of the hole for later.

As can be seen from the pictures, the use of clear perspex has another great advantage, i.e. that you can see exactly what is going on below.

There are two important things to note about the jig; first none of the pictures of it show the positions for the adjuster holes because I had to work those out later and the second, most important thing to mention, is that there are two hole positions on the jig, closest to the centre, are for holes that cannot be drilled at this stage, for the return springs, the plates for which are not yet attached, hence the two pieces of yellow tape over them.

At this stage, the two hold down pin holes are drilled, the two pairs of wheel cylinder fixing holes, the holes which form the ends of the slot for the elongated wheel cylinder port boss and now on the updated jig, the two holes for the brake shoe adjusters.

This drilling process is then repeated on the second backplate, only after the jig has been attached the opposite way up, as previously explained.

When both plates have had this batch of 2.5mm holes drilled, then both plates can systematically have their hole sizes increased, as required.

So, that is the very important bit of the process started, getting the geometry right.

The drilling table.

Ed’s note: This article is continued further on in this issue.

Crankcase pressure evacuation

The problem of oil leaking past the crankshaft seals is something that seems to plague XPAG engines so I have endeavoured to do something about it.  From the outset, my rebuild of TC 10030 has been driven by a desire to have a TC with fewer of the original poor design choices that, in my opinion, detract from what is otherwise a delightful car.  

We are all familiar with the draught tube ventilation system that is designed to draw out engine fumes and expel them to the atmosphere. This is not exactly environmentally friendly; it’s also inefficient. The draught tube system can only work when the car is moving so that an atmospheric depression is created at the end of the tube. This, combined with the internal pressure is designed to evacuate crankcase gasses.  When the car is idling or in slow traffic ‘blow by’ can build up pressure in the crank case as it cannot escape fast enough. Fumes from the crank case are drawn out the faster the car moves… but here’s the rub… the harder a car is driven, the more ‘blow by’ it will create; more in fact than the draught tube can remove and excessive pressure in the crank case will force oil past the crankshaft seals.  Obviously, the more worn the pistons/cylinders are; the worse the blow by. 

Positive Crankcase Ventilation is an emission control feature of modern cars.  The PCV valve recycles crankcase gasses to the combustion chambers where they are burned and expelled through the exhaust. Much more environmentally friendly!  I could have incorporated this system into my XPAG engine rebuild but there was a problem.  My engine will be supercharged and I had read that PCV valves are designed to work with normally aspirated engines; they do not work well with the pressure of superchargers.  I needed a different approach so when I read about how one enterprising TF owner in America had adapted an exhaust-controlled crankcase evacuation system used in light aircraft, I decided to investigate the possibility of fitting one to my TC. 

The method of crankcase ventilation utilising exhaust vacuum was my preferred option for several reasons: 

Firstly, this method will work with my supercharger. 

Secondly, it fits in with my ethos of not making any irreversible changes to the car. 

Third, this would be an environmentally friendly alternative to the draught tube. 

A fourth reason is that it will protect the new crankshaft oil seals and eliminate leaks.

The fifth reason was that I could do it myself at a reasonable price.

At the heart of the system is a “scavenger” unit which is fitted at an angle to the exhaust pipe between the manifold and the silencer. Using a piece of scrap pipe on which to practise, it became apparent that the scavenger unit I had bought could not possibly work without some modification.  I also had a tricky time making a 5/8” hole in the pipe as my drill only had a 1/2” chuck!

With the scavenger unit inserted so that its slot located with the edge of the pipe – necessary to establish the correct angle – it became evident that it couldn’t be tightened.  The reason was that the separate wedge-shaped securing tube was threaded – which clearly was wrong.  Another problem was that it had a flat rather than curved end.  Ideally it should be the same profile as the exhaust pipe.

I mounted the wedge-shaped ‘securing tube’ section in the lathe and stripped out the threads.  I then filed the end to match the profile of the exhaust pipe.  The angle was also wrong and required careful filing to match the angle of the scavenger unit in the exhaust.  Eventually I was able to tighten the unit securely to the pipe with the locking nut.    YESS!!!

This photo shows a 22mm to 15mm reducer with a short length of copper tubing on the end of the scavenger unit.

There was originally a 1” UNC threaded end which I found impossible to match to any suitable reducer so I again mounted it in the lathe and carefully stripped the threads down to a point where – using the vice – I could press on a 22mm ‘Yorkshire’ I was now ready to install the scavenger unit into the exhaust proper.  There was a moment of trepidation before actually drilling a hole in my brand new stainless-steel exhaust pipe but the scavenger unit came with a blanking plug should it all go pear shaped.  Fortunately, the fitting went well.  The expected vacuum should be in the region of 3Hg however there is some adjustment to prevent excessive oil drag.  I have a vacuum gauge which remains to be fitted.

Location of fitting of scavenger unit.

One view of the catch can location.

Another view of the catch can location (see text below)

Other important components of a system like this are the provision of a non-return valve (for safety reasons) and a catch can to prevent oil being carried to the exhaust system. I have improved the catch can with additional baffles. It has a dip stick and can be easily emptied.  It will be interesting to see how much oil is collected!  The take-off is from the breather in the rocker cover. Here I have another 22mm to 15mm reducer to take the rubber hose.   I have also fitted an adjustable brass vent in place of the draught tube.

I think, on balance, it is quite an attractive installation.  I just hope it is fit for purpose when in service. 

Ray White

The adjustable brass vent in the tappet chest, replacing the pipe.

MG TA (MPJG) Oil in the radiator problem

For a number of years, I, like many other TA owners with original type MPJG engines, suffered the problem of oil accumulating in the radiator header tank. Every now and again I would get a bent spoon and scoop out the oil floating on top of the water and wipe the internal neck of the radiator to get rid of any ‘mayonnaise’! It never affected the performance of the car, or made it overheat – it was just an annoyance!

I initially thought it was due to a cracked cylinder head, so I had the head off and had it crack tested. Sure enough, there was a crack on the top surface of the head between valves 4 and 5, the siamesed exhaust valves.

I got another head and had it crack tested; all was OK, so I built it up with new valves and guides and fitted it to the TA. I flushed out the radiator several times and filled it with water/antifreeze mix and thought my problems were over.

Sadly, after a short while, oil started to appear in the radiator header tank again; surely my new head couldn’t have cracked so soon! I magnafluxed it and it appeared OK.

Another TA owner I spoke to, told me he had a similar problem and he had cured it by fitting a modified rear rocker pillar. The oil to the rockers is fed directly off the main oil gallery via a copper pipe to the cylinder head, then via a hole in the centre of the base of the rear rocker pillar up to the rocker shaft. This oil can be up to a pressure of 60 to 70 psi and the back of the head oil gallery is very, very close to the internal water jacket in the head. It is possible that the head casting there is very thin and oil in very small quantities is forced through the porous casting into the water jacket, then via the water pump to the radiator, where it accumulates in large blobs! The cooling system is not pressurized, so no water flows the other way into the oil and the sump.

So, I purchased one of these modified rear rocker pillars and fitted it to the engine. It appears to have cured the problem as in the past year I have had no oil in the radiator. Following this early sign of success, I have had a small batch of these modified rocker pillars made and slightly improved on the one I purchased. This modification moves the oil feed to the rockers to being outbound of the back of the head where coolant is present.

Detailed below, is the procedure for fitting such a modified rear rocker pillar. This modification can be done without the need to strip the cylinder head down, and should not be beyond the scope of a competent home mechanic. You will need a couple of BSF spanners, a scriber, electric drill and a small Allen key. You will be replacing the rear rocker pillar.

  1. Remove the rocker cover and the rocker shaft, making sure that no pushrods drop down into the sump! Then disconnect the oil feed pipe to the cylinder head, and remove the male/male oil union in the head.

  2. Clean the area around the base of the rear rocker pillar, then put a clean rag into the head oil drain cavities where the push rods protrude. Cover the valves/springs with another rag to ensure no swarf gets into the engine. Place some gaffer tape around the edge of the rear rocker pillar mounting area.

  3. Scribe a centre line through the two 8mm tapped holes and current oil feed hole to the edge of the head, then mark a spot along this line 13mm from the rear edge of the outer M8 tapped hole for the rocker pillar mounting bolt. This will be the position for the new oil supply hole. Centre pop the mark and carefully drill a 1/8 inch hole down vertically through the head into the oil feed gallery. If possible, have a vacuum cleaner handy to suck away all the swarf! Then take a ¼ inch drill and enlarge the hole that you have just drilled. Clean away all the swarf from around and within the oil feed gallery.
  1. Now you will need to take the ¼ inch BSF tap supplied with the kit, apply a little drop of cutting oil (or 3 in1 oil) to the end of the tap, and carefully tap a ¼ BSF thread into the oil feed gallery. Be careful and watch the tap go through the first rear rocker pillar mounting bolt hole. It is not necessary to cut the thread all the way along the gallery. Once again, clean all swarf out of the gallery using a vacuum cleaner, and blowing down the hole.

  2. Now take the ¼ inch BSF grub screw that came with the kit, apply a drop of Loctite or thread sealant to the grub screw and using a small Allen key, screw the grub screw into the newly tapped hole in the oil gallery. You will only need to screw it in until it just goes past the rear of the new oil feed hole drilled in step 3. Finally, blow down the newly drilled oil feed hole using a short piece of tube, a cycle pump, or air-line if you have one – cleanliness is very important. Carefully remove the gaffer tape and rags from around the valves/springs and oil drain cavities.

  3. Take the rocker shaft assembly, remove the rear circlip, spring and spacer, plus No.8 rocker and the old rear rocker pillar. Fit the new rocker pillar with the oil hole outer-most and replace No. 8 rocker, spring, spacer and circlip.
  4. Refit the rocker shaft assembly, ensuring that the pushrods are correctly located. I usually put a bit of Loctite (or thread sealant) on all 8 bolts as I don’t have any lock-tabs. Do not over tighten these M8 x 1 bolts, certainly no more than 15lb/ft if you use a torque wrench. Then screw the male/male union back into the head complete with its copper washer and reconnect the oil feed pipe to the cylinder head. Quickly check the tappet clearances using the rule of 9 (adjust 3 with 6 open etc.,), 15 thou exhaust and 10 thou inlets. Start the engine and just visually check that oil is flowing around the rockers. If all OK, replace the rocker cover and run the engine until it is hot. Then remove the rocker cover and set the tappets correctly with the engine hot, replace with a new rocker cover gasket (if necessary) and then replace rocker cover.
  5. Drain the radiator and cylinder block, refill with water and a flushing agent, such as Holts Speedflush (or a dishwasher tablet) etc., then run the engine until the thermostat opens and the engine is hot. Drain the cooling system again and this time fill it with 50% clear water (preferably de-ionised water) and 50% blue antifreeze. The job is now complete.
  6. Hopefully, you will, like me, no longer see oil floating on top of the coolant in the radiator header tank.

    You can buy a kit for this modification from the MG Octagon Car Club under part number SCH051A – it comes complete with ¼ BSF tap and grub screw, plus instructions.

    BRIAN RAINBOW

    Other brands are available

    Ed’s note:

    In accordance with their mutual status, you need to be a member of the MG Octagon Car Club to purchase their spares.

    To join the Club, please go to https://mgoctagoncarclub.wpcomstaging.com/membership/

    To view the Club spares list, please go to https://mgoctagoncarclub.wpcomstaging.com/spare-parts/

TC Master Cylinder Remote Reservoir

I know this modification has been looked at before, but I think this is a slightly different take on it.  We are all aware of the difficulty in accessing the master cylinder under the floor – so a remote reservoir makes for a practical change and one which I regard as an improvement over the original design.  

As part of a complete rebuild, I have recently fitted the restored bulkhead to the chassis and it seemed like a good point at which to install the brake fluid reservoir.  I chose a replica Girling tank with a vented lid and a 7/16” UNF 20 tpi outlet. I located it in the front right-hand corner of the battery box.  Utilising one of the regulator screws, I attached the clamp to the side and fed a length of 1/4″ Cunifer tubing through a grommeted hole in the bottom of the box.  There is still plenty of room for the battery, yet the tank is neatly accommodated in a place where the fluid level can be easily checked and also avoids the risk of any brake fluid spillage onto paintwork…

The outlet pipe is made up from what I had left over from a complete brake system overhaul and, being armoured, matches the existing pipework. It follows the route of the starter cable by exiting the foot ramp but it then falls away down behind the engine and eventually emerges under the floor where it joins the master cylinder. The pipe is held securely by several P clips which make use of the emerging gearbox cover screws.  This means that no new holes have been needed!

Before flaring the ends of the feed pipe, I had to ensure that the conical nuts for the 7/16” fittings were slid on in and in the correct orientation.  Getting the pipe to bend where I wanted it to go was the most difficult part of the operation and would have been much easier if I had done that part before fitting the bulkhead …but it is always easier with hindsight!

The one part of this modification that I had been nervous about was machining the lid of the rather expensive ‘bronze’ master cylinder.  I eventually plucked up the courage and mounted the stainless- steel lid in the 3-jaw chuck of my vintage Drummond lathe. (3 1/2” centre height).   Fortunately, the lid on this master cylinder is quite thick and proved entirely suitable.  I mounted a 25/64” drill bit in the tailstock and using the centrally positioned vent hole as a pilot, fed it through the lid.  I then tapped a 7/16” UNF thread into the hole.

Due to the lack of space under the floorboard, I was limited in my choice but in the end, I chose a standard 7/16” UNF banjo fitting.  This works well as the pipe lines up almost perfectly and avoids an air lock.  Having checked for leaks and bled the brakes I am happy that the installation is robust and to a fair standard.

I hope this has been of interest.

Ray White (TC10030)

Restoration of a 1949 MG TC

I thought members may be interested in the restoration journey of my MG TC.  I acquired it in December 2017 and planned to restore it in about 3 years.  However, COVID came along, and I was able to work on it without distractions like family gatherings, or motorcycle meetings and all manner of social activities. 

As a result, I finished the restoration officially on the 13th July 2020, with the vehicle passing a roadworthy and it was then registered.  I have restored and refurbished a number of classic motorcycles over the years, but this is my first car restoration.  It will probably be my last one too, not because I didn’t enjoy the challenge, but cars take up a lot of space in my shed. 

This MG is now part of our family and will never be sold.

The MG is a TC which left the M.G. factory in Abingdon, UK on the 17th May 1949.  It was one of the later ones to come out of the factory with a chassis number of TC8723 of 10,000 made between 1945 and 1949.  The car found its way to Australia and was sold and registered in NSW.  The black and white picture is of the car, taken when relatively new.

The car became degraded and was eventually pushed into a shed where it decomposed until the mid-80s.  It was bought by a gent in Newcastle from the original owner’s family and he had it for about 20 years as far as I know.

In that time, he had the rotted wood frame replaced and did some panel work, but importantly kept it all together.

He sold the car to a very good friend of mine, (very much a mentor), who was coincidently a former police officer like myself. 

He was a bike copper in Sydney in the 60s but had a very serious fall from his bike resulting in him having to resign from the NSWPF and return to his former trade as a tool maker. 

We had known each other for 30 years, rode together and against each other in competition, and restored bikes together over the years.  He unfortunately passed away suddenly in 2014.  He had done a lot of work to the engine and drive train and purchased a lot of new parts before he became too ill to continue work on the car prior to his passing.

I undertook to sell the bikes and the MG on behalf of his widow, and did so over the intervening years.  As the MG was still regarded as a basket case, and unrestored, we had very little interest in it, so Robyn and I offered to take over the car and restore it to the standard that our friend would have done.  As a result, we acquired the vehicle and parts in December 2017.

Restoration started slowly, with disassembly of the car, assessing what needed to be done and seeking the many parts that were missing.  The best part is that virtually everything needed for them is either still available or can be remanufactured (at a price of course).

This made a pleasant change from trying to restore motorcycles of very low volume manufacturers, long passed into history.   After stripping, the drudgery of cleaning, blasting, rubbing and grinding off rust etc happened at a slow pace.

I got to the stage of being ready to paint the chassis, suspension and underside parts by October 2018.  I bought a ‘wedding gazebo’ from eBay for $75 and used it as a spray booth in one bay of my shed.

It worked really well.  However, the combination of a hot shed, inside a plastic canopy, in full protective overalls and breathing apparatus made it a very uncomfortable and hot Saturday morning spray painting.

After that it was time to assemble the engine (gearbox was complete and diff was ready to put together).

Once that was done, I assembled the suspension and entire front end, steering and suspension; the car has a Nissan steering box conversion. 

My Bishop steering assembly didn’t feel too bad, but both pitman arms I had showed weakness and impending failure after a magnaflux and x-ray test.  As this car will be a definite driver, I opted for better and safer steering over originality.  This is one of the very few departures from a faithful restoration.

There were lots of parts to make and refurbish so the lathe and mill were working in overdrive for a few months.  Once up on wheels, the engine, gearbox and diff were offered up to the vehicle in mid-2019.  Then came installing the brakes, steering column and connecting up all the steering parts. 

The body was examined and any panel work was done as best I could (most of it had been done by the previous owner). The timber frame had been made and assembled to a high standard, and I acquired the floorboards by a happy coincidence. 

The rest of the timbers, and ply parts were made by constant referral to Mike Sherrell’s excellent book, lots of marine ply, a scroll saw and circular saw.   The body, and panels were then transported to the spray painter to have that lovely MG Red sprayed, whilst all the stuff that was chrome was taken to the chrome works over East Bundaberg.  I am happy to say that all restoration services I used were local and there was no need to send anything away.

As the car slowly came together, I continually identified things that were needed and, after searching through the parts I had, ordered parts from Australia, the UK and USA that I didn’t have.  I got a bit of fright with some of the postage costs, but what choice do you have?

In late October, I had the body returned to me in bright MG Red, and it was assembled onto the rolling chassis with the help of a few strong friends.  Once that was on, Rod from next door helped me with wiring and many other tasks – Rod is very multiskilled in things electrical and mechanical and freely gave up many hours of his time to help with the final assembly. 

The car then went into a local upholsterer who did a breathtakingly beautiful job on the seats, trim and carpets inside the cabin.  The car is trimmed almost totally in fine beige leather, probably much better than the original job.  I have left the making and fitting of the hood and side curtains until after the car was on the road.  I did refurbish the badly damaged hood frames an undertaking that took the most time of any singular part of the car. 

I got the chrome work back just before Christmas and started assembly of the pretty bits.  This allowed me to fit things like the fuel tank, connect up the fuel lines, and fit the lovely dashboard.  That took me up to the end of February and the start of COVID lockdown.  By the end of April I had all the panels fitted and my brother helped me start the car after he’d diagnosed a problem with the distributor that prevented it from kicking over. 

It was a huge relief when the car burst into life and it sounded very nice.  No strange noises or oil leaks!  About that time, I drove it up and down my long driveway and was confident everything would be OK.  The motor is virtually new with full crank rebuild, new liners and pistons, full head restoration and new cam.  The ignition has been converted to electronic ignition.

In May 2020, I fitted the front guards and bonnet (which takes ages as all the body panels are literally coach built so have to be fitted, taken off, modified, fitted again and so on until it all fits together correctly.  The fitting and adjustment of the bonnet alone took almost a day for Rod and I.

By the time I left for Townsville in mid-June, the car was more or less ready for roadworthy inspection prior to registration.  Upon our return, some time was spent going over all the car for a final check over before calling the inspection mob.

On the 13th July the M.G. passed the roadworthy and I was straight down to Queensland Transport and registered it.  Robyn and I then went on a short trip, and it is lovely to drive.  All the work has paid off, and we look forward to using it for club activities as much as possible.  We have now done about 200 miles and still no oil leaks or any major issues.  Then it was then taken back to the trimmer to have the hood and side curtains made and fitted. 

Since being on the road, I have now completed about 400 miles.  Tuning has been a bit of a nightmare, as first of all I could not get a good carb tune; this turned out to be a very small fracture in one of the floats that caused it to slowly fill with fuel.  Once that was discovered and new floats purchased, it was much better.  Then I had a strange misfire when the car was at operating temp which got progressively worse as the car got hotter.  It idled nicely, and responded well to light throttle openings, but had a massive flat spot when accelerating normally.  Once the car levelled out at a particular speed, it was OK.  Having exhausted carb fiddling, I reckoned it was perhaps advance/retard issue and checked that to no avail.

In desperation, I replaced the electronic ignition with the original points/condenser setup and immediately it was a very different car.  Performs faultlessly and the performance is remarkable as well.  Not mentioning the ignition type as I am still talking with them, but when it came, the cam pick up was very loose on the points cam.  I called and was told to take up the gap with electrical tape until it was tight.  This sounded dodgy but did it.  I believe that the tape softens when hot and allows the pick up to move in relation to the points cam thereby changing the timing particularly when intertia of accelerating the vehicle is in play.  That is my working theory at the moment.  Or it may be simply a faulty ignition system. Anyway, I am running on points and thoroughly enjoying the MG.

On the road at last!

Rowan Bond

Ed’s Note: Rowan initially contacted me for a pair of “Dave’s Doughnuts”, which have successfully arrived in Australia. It was through this contact that he mentioned the article, which I was pleased to receive and publish.

Is your cave full of useful junk?

In 1967 I was 16 when I bought my TC for £60 from a teacher at school. Although it had an MOT it was not in the best condition. My father and I spent the next two years stripping it down to the chassis and “patching” it back together to make it road worthy. I had no money for anything more.

Nearly everything I took off and replaced ended up boxed in my bedroom. My mother used to say “why are you saving all that rubbish, you will never use it again”. As I have grown older, I have continued to squirrel away “rubbish”. Yes, I still have the bits from 1967 and yes, my mother was mostly right. You never know when things may come in useful. A half shaft that broke in 1973, is now new pivots for my brakes. I have even kept the broken end as a souvenir.

My garage is full, not just with cars; I have pieces of wood, boxes full of all sorts of “useful” things, pieces of metal, assorted nuts and bolts, wire, bits of pipe – not to mention a stack of worn or broken TC parts. Need I go on? The list is endless.

I am sure I am not alone. This raises the question, why do we save things that may be useful?

I have a theory to explain this behaviour. I blame evolution.

Humans are the most successful mammals on the planet. The main reason, our big brain. A brain which depends on a high protein diet. We are, in the main, carnivores to support our big brains. Compared to other successful carnivores, we are not even in the same league. Long sharp claws, no; big canine teeth, definitely not. When modern man evolved some 200,000 years ago, what then made us successful hunters?

We relied on tools, spears, bows, flint knives and axes to kill and butcher our prey. The success of our ancient ancestors as carnivores depended on the quality of their tools. A broken spear, a missed kill, could mean starvation for a family and the end of those genes.

Imagine a hunter who, when they saw a nice straight piece of wood, thought “humm – that will make a good spear handle. I will take it back to my cave. It may come in useful one day.” The wood probably joined a handy lump of stone, a nice looking piece of flint and a plethora of other things. When this hunter’s spear broke, somewhere at the back of his cave, he had a new handle ready to hand. Soon back to hunting. Natural selection favoured those with the inclination to collect and store things. Need I say more?

In evolutionary terms 200,000 years is nothing. We no longer use spears or stone axes, but the bolt…, the bracket…, the broken half shaft…. This list goes on. You never know when something may come in useful. All we are doing is following our evolved behaviours. Behaviours that made the human race so successful. At least, that is my excuse. You can take this analogy even further. Whenever my wife and I go on tour with other MG owners, I often get accused of spending too much time in the car park talking about boring old crank rods or comparing push valves.

You can imagine a conversation between two of our ancient ancestors. “Hey, that’s a rather nice looking spear, how many boars have you killed with it. Six! That’s fantastic. What makes it so good? It is the sharp piece of flint on the end? Mine is only fire hardened wood. Where did you get the flint and how is it fitted? In my view it is definitely worth upgrading your spear”. The better the tools, the greater the chances of evolutionary success. Learning how others have improved their spears is a great way to improve your chances of survival.

We no longer have spears, just classic MGs. “Is that a supercharger? How is it fitted?” We are still cave dwelling hunter-gatherers at heart.

Paul Ireland (evolved from cavemen and women)