Category Archives: Issue 15 (December 2012)

Weeping and Gnashing of Teeth

About 18 months ago I restored the engine of my TA. After a few hundred miles, water started to disappear from the radiator; maybe half a litre a fortnight. I tightened the clips on the hoses but the leakage continued unabated. I then noticed brown water run marks, apparently from the cylinder head, down the driver’s side of the block just below the front head stud. I took off the cylinder head, terrified of finding that I had cracked the block in tightening down the head. TG it was OK.

I replaced the head, using Wellseal on the head gasket and filled the radiator. After a day or so, water drops could be seen down the side of the block in the same place as before. There were also water runs down the side of the block beneath two other head studs.

I then noticed drops of water on top of the nuts which bolt down the head, and finally the penny dropped. On my engine at least, the head studs protrude into the water jacket. Water was oozing up the thread, through the stud holes in the head gasket (I obviously hadn’t put enough Wellseal around them), past the studs through the head, up the thread of the nuts and out into the world. The reason that it didn’t leak at first was that I had used plenty of grease on the stud threads and it had taken some miles before the grease had melted away.

Next time the head is removed (hopefully long after my time) it would be advisable to remove the studs from the block and put them back with an appropriate water sealing compound. Pending that, I removed the nuts one by one (including the ones inside the rocker box cover), wrapped PTFE tape round the threads, selected pristine new washers and replaced the nuts. They haven’t leaked since and that’s about 2,000 miles ago.

Realising that water could also have oozed past the nuts inside the rocker box cover and into the oil, I loosened the sump plug and sure enough, quite a bit of water came out before any oil. The inside of the breather pipe was also thickly coated with an unspeakable, slimy grey oil/water emulsion. It was a narrow escape; the engine could so easily have melted main or big end bearings or seized up entirely.

Some time later I replaced pitted cam followers with newly ground ones. This entailed removing both cam follower blocks. When the front one was taken off, water came out of the front bolt hole. If I say it pxxd out it will give the right idea. On my engine at least, the bolt hole obviously breaks into the water jacket. I sealed the bottom of the hole with an araldite/PTFE plug and it seems to be OK, though I now keep an eagle eye on the water level in the radiator. To be looked into next time the engine is out . . .

So, you MPJG owners, if your water level drops, check the two obscure leakage paths I’ve discovered before doing anything more radical !

Lastly, when first started after a few days of not being used, the clutch sticks and it is impossible to engage gears without a terrible grinding. With the ignition off, I have to push the clutch fully down, put the car in gear, brake hard and pull the starter. The car twitches, the clutch un-sticks and the engine spins over. Thereafter it’s fine. However, it doesn’t seem like a nice thing to do.

Has anyone else experienced anything like this?

Adrian Sheppard
Isle of Wight

MG TC Front Axle Castor Angle

This summer, my TC was displayed along with other vintage, historic & classic cars at our local village fete. I got talking to someone who was staying with relatives in the area and who’d recently purchased a TC (although not available on the day). On discovering my car still retained the Bishop Cam steering box, he said he found his car had a tendency to wander on straight roads. I advised him to check the castor angle as well as checking the steering box was correctly adjusted (i.e. correctly shimmed – unless he had the aftermarket Tompkins screw adjustment cover plate), check the ‘toe in’ was correctly set and no significant ‘play’ in the king pins, drag link and track rod ends.

Since he was interested in understanding the castor angle, I recounted my own experience when purchasing my 1946 TC in 2003. I bought my car from a classic car dealer (in fairness to him not specifically an MG dealer) who simply commented “like many older cars with worm & peg steering boxes, don’t expect the steering to be pin sharp”.

As purchased, the steering was very sensitive with very little self-centring action. The steering box did need slight adjustment by removing a 0.005″ shim and with the top plate off I took the opportunity to fill with ‘Steering lube’ which is a liquid semi- grease (as thick oil tends to drain out of the box through the drop arm seal and grease is so thick the action of the follower peg in the worm simply deposits it on the sides of the box, depriving the moving parts of essential lubrication).

However the real culprit was a lack of castor angle caused by the axle being fitted back to front during some previous rebuild – and this is not an uncommon occurrence! Mike Sherrell’s book TCs Forever! and a number of other publications explain the castor angle set up. Castor is achieved when a projected line drawn though the centre of the king pin touches the road ahead of the tyre contact point and provides a self-centring action (think of the castors on a supermarket trolley).

The castor angle is simply the angle that the king pin leans backwards from the vertical to enable the projected line to be ahead of the centre of the tyre contact point. The greater the castor angle the more the self-centring effect (but also the harder it is to turn the steering wheel at low parking speeds), so MG designed the steering geometry to achieve a balance between straight line stability and ease of low speed manoeuvring.

When correctly set up and taking the weight of the car (providing they’re not worn or sagging), the front springs of a TC rise up forward by 5 degrees from the horizontal. In comparison with the king pin axis the underside of the front axle mounting pads are set 3 degrees from horizontal which means if a loose axle is placed on a flat surface the king pin axis will lean back by 3 degrees. When correctly installed on the car the total castor angle is 8 degrees (5 degrees on the spring and 3 degrees cast into the axle). But of course, if the axle is reversed by being incorrectly assembled off the car during a rebuild with the LH and RH stub axles fitted to the wrong side of the beam axle then when fitted to the car the castor angle is actually reduced to only 2 degrees (5deg minus 3 deg).

Mike Sherrell’s book states a first indication as to whether a TC front axle has been reversed is that the cast in lettering on the axle beam should be to the rear of the car (i.e. not readily obvious from the front). A number of MG dealers I talked to were slightly sceptical as to whether this generalisation applied to all TAs, TBs & TCs (to be fair Mike only refers to this with TCs) but certainly a sure fire way of confirming if the front axle is the correct way around is that the round heads of the king pin retaining cotters should be at the rear and the cotter nuts to the front of the axle. (i.e. the head of the king pin cotter acts as a steering stop with the bolt at the back of the stub axle).

On TCs built from late 1947 onwards, MG installed 2.5 degree wedge plates between the axle and the spring. Fitted from the rear of the axle this had the effect of rotating the axle forward reducing the castor by 2.5 degrees to 5.5 degrees. MG did this in response to complaints from the USA that American women were finding the TC steering heavy when parking. I and many others would advise removing these later wedge plates to regain the earlier cars’ better straight line stability with 8 degrees castor.

However, these 2.5 degree wedge plates (available from Moss and others) do have one useful function. If like mine when purchased, your car has a reversed front axle you can’t just turn the axle around since this would cause a major safety issue regards reversing the left hand and right hand stub axles & nuts even when you change over the hubs and back plates to the correct side etc. Therefore until I removed and fully rebuilt my front axle correctly, as a temporary measure I fitted these 2.5 degree wedges between the axle and the springs but from the front so rotating the axle backwards and improving the castor from 2 degrees to 4.5 degrees.

I’ll admit that whilst I was planning improvements to enable my TC to keep up with modern traffic I considered fitting the Datsun or VW steering box conversion as well as the 5 speed HI-Gear Ford gearbox etc. But in truth, since I’ve got a tubular extractor manifold on my stage 2 engine the modern steering box wouldn’t fit. Therefore I’ve kept a correctly adjusted standard Bishop Cam steering box, which together with NDT crack detected drop arm, reconditioned front springs, John James’ polyurethane shackle bushes, new stub axles and Roger Furneaux’s taper roller front bearing conversion in new hubs, the steering is precise with good straight line stability.

A final modification I’ve carried out recently – more for fun than any real need on a road car (and a possible thought of club hill climbing at some future date as it’s normally a track conversion) – is to fit a new rose jointed drag link and track rod and a front Panhard Rod which better locates the front axle and takes out the sideways lateral movement inherent with the bushed shackle spring retainers.

This makes no – or only very marginal – difference under normal driving conditions but the car is better poised under hard cornering. The TA and TB’s front springs were retained at the rear by sliding trunnions which gave a better lateral location (being developed from MG’s racing experience through the 1930s), but as these tended to wear quite badly on higher mileage road cars they were changed on the post war TC to the harder wearing bushed shackles.

Mike Harvey

Ed’s note: The 2.5 degree packing pieces were introduced at chassis number TC4251.

The castor angle at the axle base is 3 degrees for the TA, TB and TC; this seems to indicate to me that the front axles were the same for the TA/TB/TC.

The (total) castor angle on the TA and TB is 6 degrees, 3 degrees at the axle base and 3 degrees on the chassis. So the difference in (total) castor angle (6 degrees, compared with 8 degrees) must be due the difference in spring mounting at the rear of the spring from a trunnion arrangement to one of shackles.

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Bits and Pieces

Not much room for this item this time I’m afraid.

Leaf Springs for MG TC Six pairs of TC front springs have been made with an enlarged (5/8”) front eye to take a i/16” bronze bush. The cost per spring was £90 plus VAT and those who ordered them have been separately notified. The cost of the bushes, fitting and reaming has to be added to the unit cost of the springs.

Large Rear Shackle Bushes for the TC These are now in stock and cost £4 per bush. A sachet of assembly lubricant is supplied with each pack of four (4) bushes and the UK postage cost is £2.20. EU and ROW postage is around £3 and £4 respectively. Packages have been sent out to those on the waiting list. If you haven’t received yours yet it may well be that I forgot to add your name to the list! If so, please contact me again and I’ll send by return. Tel: 0117 986 4224 e- mail jj(at) {please substitute @ for (at)}

Interleaf pads on TD/TF (and Y) rear springs Nothing ever goes smoothly! The intended supplier quoted for Acetal when he was asked to quote for Nylatron. I have to try elsewhere but there will be a delay due to family commitments.

Steel Crankshaft and rods for the XPAG I am in discussion with a Midlands based manufacturer of crankshafts and rods to supply a small batch of XPAG cranks and rods. At present I know of three (3) owners who have expressed an interest. The cranks would be in EN40B material and the rods of H section. It is early days yet but the likely cost is around £1900 plus VAT for each set of crank and rods. The contract would be between the purchaser and the supplier.

If you are interested, please contact me (phone number and e-mail address as for the shackle bush item).

TA1096 (Registration number JK 6672)

Paul Longbottom has e-mailed to say that he thinks that his car might have had some competition history. If anybody recognises the above registration number Paul would be grateful if you would contact him at plongbot(at) {substitute @ for (at)}.

TC2965 (Registration number DUJ 867)

A past owner, Robert Heppell (01386 860499) has a bill of sale (signed over a 2p stamp!) from when he bought the car from the second owner, Rosemary Newton of Church Stretton, Shropshire in 1976. It is said that Rosemary was given the car by her employer, Major Wolfe in 1961. The Major bought it from new in 1947 until he passed it on in 1961. Robert would like to hear from the present owner.

Kimber Festival Call for Papers

The New England MG T Register is seeking proposals for papers to be presented at its Kimber Festival to be held in Bennington, Vermont, USA, from April 12 through 14, 2013. The Kimber Festival brings together enthusiasts who are keenly interested in M.G. history. Organized as an academic conference, the program consists of presentations about all M.G.s with topics that may include design and production, technical discussions, competitors, and competitions. Papers about the last MGB will be as welcome as one about the first M.G., Old Number One. Presenters pay all of their own expenses, as there is no budget for honorariums.

After check-in at the host motel on Friday afternoon, there will be an “in room” literature/memorabilia swap meet for early arrivals. Attendees will have an opportunity to sell, buy, and swap extra items from their collections. There will be ample time for renewing friendships as well as making new ones.

On Friday evening, April 12, the attendees will celebrate Cecil Kimber’s 125th birthday at the Hemmings Motor News museum. Along with a birthday cake there will be a keynote presentation designed to set the tone for the rest of the weekend.

The Kimber Festival moves to the Bennington Museum for all of the Saturday activities. This venue has perfect meeting rooms for the presentations while containing an outstanding collection of Vermont historical items. In addition, the museum holds to world’s largest collection of both Grandma Moses’ paintings and Bennington Pottery.

Proposals for papers on subjects related to the old car hobby will also be welcomed. A few years ago, for instance, we had a presentation about flower arranging using M.G. parts. Following the Festival, a certain number of the papers will be selected for publication in The Sacred Octagon, the Register’s magazine.

Proposals should include the title of the submission, names and affiliations of presenters, together with addresses, phone numbers, email addresses of contact personnel, proposed format (paper, panel, workshop, etc.) and a short abstract describing the content of the presentation. A computer projector will be available for power point presentations.

Proposals must be received by December 31, 2012; notification of acceptance is anticipated by January 31. Proposals should be submitted to: Richard L. Knudson, 9 St. James’ Place #207, Oneonta, New York 13820 USA, email preferred to FC7900(at) please {substitute @ for (at)}

Back Cover Photos

Above: Milly Player in her smart duotone red TA Tickford, TA3079 at GOF Central MK XXXIV hosted by The Vintage M.G. Car Club of Chicago in Summer 2012. Below: Bill Hentzen arriving at the GOF in TB Tickford, TB0437.

Above: Panoramic ‘shot’ of the participants at GOF CENTRAL MK XXXIV hosted by The Vintage M.G. Car Club of Chicago this summer. More than 200 came from all over the U.S.A. Below: TA/TB Tickford Reunion, Chicago 2012 – Phil Laiacona, Trumbull, CT; Jim Williams, Cincinnati, OH; Lee Jacobsen, Dearborn, MI; Bill Hentzen, Mequon, WI; Len Star, Hudson, OH; Milly Player, Lancaster, SC. *Click photos for bigger versions*