Category Archives: Issue 5 (April 2011)

Replacing Rear Road Spring Front Hanger on TA 1957

The author’s TB

Chassis TA1957 had hung on the wall of my garage for around 30 years and I decided recently to refurbish it with a view to building up a car from the bits and pieces I have accumulated since I bought my TB around 1970.

Generally it is in good condition, fairly straight but with a few splits and cracks and badly butchered rear spring front mount spigots. I decided to replace these as someone appears to have used a drill to remove the metalastic bushes plus they were pitted with deep rust.

I had no previous experience of removing these spigots, but from inspection it was clear to see that they screw into the chassis cross tube under the rear body support brackets which are riveted to the chassis.

On the near (left hand side looking to the front) side a vertical tapered pin sticking out top & bottom was clearly visible. This knocked out easily and the spigot unscrewed without trouble although spanner travel was minimal due to the spigot being enclosed by the body bracket. Simple eh?!

After removal I noticed that the cross tube had 2 small raised areas showing on the outside which had not been visible before. These turned out to be metal plugs which filled 2 holes in the tube at right angles to the pin position – see photo 1, i.e. horizontal, where, clearly, another taper pin had previously been. I assumed from this that the original pins were placed horizontally and that this spigot at least had been replaced during the life of the car.

PHOTO 1 – Near side showing original and later pin positions.

The off side had no visible pin showing despite cleaning up and using a magnifying glass to try to identify any blemish or mark to give me a clue. Was the pin vertical or horizontal? I decided that the only way to determine the location of the pin was to cut off the spigot and drill into the remaining metal to expose the pin inside the tube but leaving the flatted section so that the spanner could be used later to remove the remains. After a bit of sawing, angle grinding and drilling I could see inside the tube.

PHOTO 2 – Offside with pin nearly out – note split outrigger permitting pin removal.

The result of this was that the pin was horizontal, which was to be expected from what I had found on the near side. With careful measurement I marked the pin position on the outside of the tube, made an intelligent guess about which way it tapered (I could see it inside the cross tube using a torch but the taper is not easy to see) and with a hammer and drift knocked it out. It was surprising that this pin was initially invisible from the outside and one must assume that these were ground off flush with the cross tube as part of the manufacturing process.

It does appear that when the cars were manufactured the spigot was pinned in place prior to being fixed in the chassis as it would seem that the pin cannot be inserted with the body outrigger properly fixed – see photo 2. The pin hits the outrigger metal – not a problem on mine as the outrigger was moveable due to vertical splits in the metal adjacent to the rivets.

PHOTO 3 – old spigots removed

Interestingly both threads on the spigots where they go into the cross tube were clean and shiny. I expected water penetration to have rusted these over the years – see photo 3 (right). I have purchased new spigot units from NTG – (“can’t remember the last time we sold any of those”) and taper pins and reamer from BBN Online. The taper pins are 3/16 x 1½ inches imperial taper.

I’ll fit the taper pins vertically as they can be pushed in through the circular hole on the top of the outrigger.

I’m hoping the refit will be easier than the removal. If it’s not I’ll let you know. I had to buy 25 taper pins so if you ever contemplate this job let me know as I can’t imagine I will be changing another 23 spigots in the future!

Finally, as far as I am aware these spigots are the same on the TA, B and C.

Jeff Townsend

Ed’s note: Jeff used to race his TB. If you have a copy of Chris Harvey’s book “MG The Immortal T Series” you will find a colour plate of JPC 901 on page 90. The photo was taken at Silverstone – the car was red in those days.

Bits and Pieces

We have a real ‘mixed bag’ this month! I start with some spares news:

POLYURETHANE BUSHES

Mention was made in February’s TTT 2 that I was having a mould made in order to be able to supply the suspension bushes on the TC (not, for the time being, the large bush on the lower rear) and the rear spring eye bushes on the TD/TF. A recent enquiry of the supplier as to progress revealed that progress is slow (a reference was made to delay caused by the snow – but that was months ago!) Obviously, in the words of the late Eartha Kitt, “An Englishman needs time!”

TA/B/C FRONT SPRING PINS

Although I have only just put the order in, I have a feeling that I will have these pins before I see any poly bushes! Just for clarification these pins are the ones which pass through the eye of the front spring and screw into a threaded insert in the front chassis tube. They are being made from SAE/ANSI 8620, a nickel molybdenum case hardening steel. It’s tensile strength is around 850 NM/mm2 after hardening – almost certainly, a superior spec than the original 1940s material.

The price will be £12.50 per pin (supplied on a non-profit making basis) plus a voluntary donation to TTT 2 of £1.50 per pin.

MoT TESTING FOR OLDER VEHICLES

I need to crave the indulgence of some overseas readers (probably, mainly those in the US) for this news item.

In the UK, all vehicles over three years old have to undergo an annual Ministry of Transport (MoT) inspection. I am aware that there are also vehicle test arrangements in France and Germany.

It has long been argued that in the case of historic and classic vehicles, which are normally well maintained and generally do not cover many miles in a year (and statistically have a very low accident rate), the annual MoT test is something of a “bureaucratic hurdle”.

Against this background, there was a meeting in late January between the All Party Parliamentary Historic Vehicles Group (APPHVG) and the Transport Minister, Mike Penning. Representing APPHVG were its President, Lord Montagu of Beaulieu and its Chairman, Greg Knight, Member of Parliament for East Yorkshire.

The well rehearsed arguments in favour of an exemption for historic and classic vehicles were advanced at the meeting and whilst there was an acknowledgement by the Minister that historic and classic vehicles are cherished by their owners, who want to ensure that they are well maintained, there is also evidence (presumably, from MoT failures!) that “the MoT test is important in helping to ensure that cars are safe for use on our roads”.

The Minister will now arrange for officials in his Department to examine the pros and cons and it is then likely that the issue will go out for consultation to interested groups.

Whilst an exemption from annual testing of our cars has its attractions, one only needs to refer back to the “TC Steering: Understanding End Assemblies” article in this magazine to ask yourself what might have happened if there was no requirement for an MoT test and the ball joint had eventually parted from the drag link, leaving the owner with no steering.

On balance, I think I would prefer to put up with what is undoubtedly an annual chore in taking the car for its annual inspection, but I believe that there is a strong case for a much reduced fee on the basis that an inspection of our vehicles can be carried out in half the time taken to inspect the modern ‘Eurobox’.

ETHANOL IN PETROL

As if there wasn’t already enough doom and gloom about, we face the challenge of various Governments’ love affair with bio-fuels. Whilst I do not want to sound alarmist, the end result, if the bio-fuel lobby really takes hold, is that our cars will not run.

Who says? Well, a major conclusion of a report by a company called QinetiQ, is that if 10% of ethanol (referred to as E10) is added to petrol then 8.6 million carburettor and first generation fuel injected cars in the UK will not run. To quote from the report:

“Field experience, vehicle trials and laboratory testing have demonstrated carburettor vehicles and powered two wheelers will suffer problems due to material incompatibility, corrosion and drivability problems”.

QinetiQ was commissioned by the Department of Transport to study the technical impact of the introduction of higher levels of bio-ethanol into petrol. This was in response to the planned introduction of E10 fuel from 2013 in conformance with EU directive 2009/30/EC, which increases the maximum permissible content of ethanol in petrol from 5% to 10%.

Here in the UK and in Europe it is currently mandated that 5% of transportation fuel must be derived from renewable sources. At present most oil companies are meeting that obligation by putting ethanol into diesel.

There is a glimmer of hope on the horizon as the QinetiQ report recommends that E5 should not be phased out from 2013 but should continue to be widely available for the foreseeable future and that consideration should be given to maintaining a specification for E0 fuel (fuel with no ethanol) for historic and vintage vehicles. However, haven’t we heard it all before with leaded petrol availability?

Clearly, there is a pressing need to do some lobbying to seek a guarantee around maintaining a specification for E0 fuel. Perhaps I am being naïve but it occurs to me that a good starting point in the UK would be to seek the views of the All Party Parliamentary Historic Vehicles Group. I intend to do just that and will report back in due course.

Finally, a sobering fact; over a third of the domestic corn crop in the USA is consumed by the US ethanol industry and demand is forecast to continue to grow.

THOSE WERE THE DAYS! TB0613 (GGO 173)

“The picture taken at Brands Hatch in about 1961, shows the result of running with radiator muff still in place and 7000 revs coming down the hill from Druids. The engine expired at Clearways. However the MG managed to get back to North London but of course required a major rebuild.

On strip down it was found that the engine had seized and if I remember correctly a con rod was bent. The bore was found to be at maximum so liners would have to be fitted.

Enter “Roy Rogers” – the name will become relevant later on. He was an engine builder found through the pages of “Safety Fast!” We took the engine to him, although on arrival the workshop was a barn with dirt floor – not a good omen! It was decided that he would bore the block and fit liners and then rebore to suit the new pistons.

Sometime later we called at the workshop to check progress. The block had been bored to accept the liners and he was about to press them in. The block was placed directly under the door lintel and an Acro jack placed between the liner and the door lintel. Three liners were pushed in, the fourth however fell in under just the weight of the Jack. Oh dear!

With that “Roy`s” mate “Tonto” called in. “No problem” he said, “centre pot all round the outside of the liner, which will raise a burr and make a good fit”. Even the cowboy engine builder looked a little embarrassed at that suggestion. It was agreed that Roy would obtain an oversized liner and fit that.

In due course the block was collected and Derek rebuilt the engine and refitted it in the TB. All was well for a while until one particularly cold morning the engine seized when the starter was operated.

On strip down it was found that a liner had slipped and locked against the crank and yes, the liner had been centre potted!”

John Maddocks

Ed’s note: John sent me this account of 1960s precision engineering. He recalls that In the early 60s a friend, Derek Waters – Derek is referred to above – owned TB0613 and it was raced, hill climbed, rallied and everything else. It is one of John’s most treasured memories. He adds that one could guarantee that all journeys would be an adventure and so exciting. The car still exists according to the ‘T’ Register and lives in Oklahoma, USA. However, John’s efforts to locate the owner have come to nought.

Here’s another photo of TB0613, taken at a hill climb at Marlow, Buckinghamshire in the early 60s. Note the change of colour (to red from white).

Derek Waters recalls buying the car from a second hand bombsite dealer in the Shoreditch area. He was told that the car had been stored on chocks for most of the war period. He thinks he sold the car to the Chequered Flag sports car company in West London, who told him that the car had gone to New Zealand.

If anybody has any news of this car, please contact the Editor through the ttypes.org Contact Form.