Tips and Comments

TD engine/gearbox mating
During the rebuild of my early (1950) TD I discovered that in my box of bits which made up the engine and gearbox, the original engine (XPAG TD791) was supplied with a late gearbox mated to an 8 clutch housing.

As most TD owners will know all the books and reference manuals, including W E Blower and the Workshop Manual warn that introduction of the 8 clutch neither the engine unit nor the gearbox unit separately is interchangeable with previous engines . The reason given is because the clutch thrust race is in a different position relative to the bell housing and gearbox.

Well, as my car arrived in many bits I decided to investigate the best way of making use of the parts I had, that is those which all manuals warn you against, early engine and late 8 bell housing and gearbox.

What I discovered is that, providing you move to the later clutch rod rather than the cable, and providing you adjust the length of the rod (plus half an inch in my case), you can happily mate the later gearbox and take full advantage of all the progressive changes this brought.

As I was exploring what for me was new territory, I decided to make the clutch rod adjustable in length. I did this by adding a screw section with locking nut which enables rod length changes of around the + half mark to be made.

I would be interested to know if anybody else has made this change and if so what adjustments were necessary to ensure satisfactory clutch operation.
Jonathan Goddard, Farnborough, Hampshire.

XPAG Oil Filters
Following the article about alternative APAG oil filter plumbing, one possible improvement to the copper oil pipes does exist. The original pipes were 3/8 dia with a thickness of approx.20 SWG (0.036 ) silver soldered into beef banjo or flange fittings. Such an arrangement results in stress concentrations where the copper pipes leave the rigid fittings.

The pipes can be strengthened by using copper tube with a thicker wall, e.g. 16SWG (0.064 ) which is still available. The bad news is the expense; a 12ft length (the shortest available) costs £37 plus a hefty delivery charge.

If enough interest is shown, as I anticipate may well be the case when existing oil pipes are examined, then perhaps strengthened replacements could be held in the Club spares stock? (Suitable tube can be obtained from J.Smith&Sons (Clerkenwell) Ltd, St. John's Square, EC1P 1ER who have depots in several towns). (I have kept a copy of the info and passed one to Harry - MT)
Eric Worpe, Guildford, Surrey

Door Safety Device
This is not a new idea, I first used it in the 60s. It is simple, cheap and effective and is less obvious than the lavatory door bolts that are often used. It can be removed with little trace if you want to enter car-cleaning competitions. The leather strap should be tight enough to allow it to just slip over the latch knob when the door is properly closed. (See photo.)
Mark Martin, Overijse, Belgium

My good friend, John Popham, whose TF1500 appeared in the colour centrespread of the December 1996 Bulletin, was in general very pleased with the car during the couple of years in which he had owned it, except for two problems:

1. It sucked an inordinate amount of oil from the rocker cover into the front carburettor air cleaner (and then distributed it around his engine bay); and
2. It dropped out of third gear on the over-run.

We tried all the usual measures for curing the first problem, which was obviously being caused by rocker chamber pressurisation - making sure the breather pipe wasn't blocked, making sure that the side plate gasket had vent holes in it, putting a restrictor in the pipe between the air filter and the rocker cover, etc.- but all to no avail. The problem was aired among other interested parties and the two most popular theories were either defunct valve stem oil seals, or gummed-up piston rings caused by the several years lay-up which the car had experienced before John brought it.

Anyway with the end of the season approaching, John decided that he would take off the head and have it converted to use unleaded fuel. This would automatically solve any valve-stem oil seal problem and whilst the head was off we could see if the pistons were unduly waggly in the bores.

So we removed the head and John took it to Beaulieu where it was handed over to George Edney to give it the treatment.

The engine turned out to be on standard bore with no discernible wear and no sideways movement at all on the pistons.

John then had a wonderful idea. As the engine was half dismantled already, how about us taking it out altogether and I could sort out his gearbox problem while we waited for the head to come back!

Now over the years I have rebuilt dozens of engines but have always steered well clear of gearboxes. Some of mental block I suppose, brought on by the thought of springs and balls flying all over the place, and only the vaguest understanding of the operation of a synchro hub.

So here was a moment of decision. Should I do the sensible thing and decline, thus shattering John's complete (though misplaced) faith in my ability to cure all T-types ills, or should I go ahead and risk the very real possibility that we could be left with a lot of cogs balls and springs, desperately looking for gearbox rebuilders in the MG magazine adverts?

He must have sensed this from the long pause before I answered (and no doubt the stricken look on my features), as he said Don't worry if it is going to be too much for you. I've got the name of a chap in the club who is supposed to be very good with gearboxes.

That decided me. Absolutely no problem, John I said, in what I hoped was a confident voice. When can you get the engine crane?

So out came the engine and gearbox.

N.B....If you are thinking of doing this, do note the instructions in the manual and take out the seat, carpet, floorboards, remote change and gearbox cover before you start. It may be a pain, but not as much as having to do it with the gearbox half in and half out.

Rather then rebuild the gearbox in John's garage, I deemed it a wise precaution to take it back to mine, As all my tools are there. What other reason could there be?

I pored over the workshop manual - never could quite grasp those sectional drawings with all that cross-hatching and shading. The supplier's parts catalogue proved much more useful for identifying the various bits. But how to get them like that? And even more to the point, how to get them back together again?

Assistance in my hour of need appeared in the shape of a couple of pages torn out of a magazine called Sports Car Mechanics dated July 1983. The author, who apparently owned a TF, had rebuilt his gearbox and taken photographs and jotted down notes for others who wished to do the same, as he felt that the workshop manual left a great deal to be desired. The notes eventually turned out to be a godsend. The photos were less helpful as the captions had been lost in the post but the magazine had printed them anyway.

However, on an initial scan through these notes I felt my professed self confidence begin to evaporate, like T-type petrol on a warm Summer's day.

Note 4:- 2nd gear is similar, except for a split thrust washer behind the collar, which the needle rollers run against. Note that the grooves on the 3rd gear collar fit over the tabs on the thrust washer, whereas the grooves on the 3rd gear collar must face away from the needle rollers . Er... Yes, well... We'll leave that for now and move on to note 5.

Note 5:- Dismantling of the 3rd/4th hub and 1st gear are best done inside a polythene bag... Oh No! ..OTHERWISE SPRINGS AND BALLS MAY FLY ALL OVER THE PLACE I knew it! And even worse .. it is almost impossible to reassemble these hubs without peening the balls into their holes first.

There then followed a list of critical end-float measurements which had to be observed, and instructions to turn up new thrust washers and the like which made me realise that this TF owner was more than your average DIY spanner wielder.

I took several deep breaths to stem the mounting panic.

The gearbox sat on the bench starting at me malevolently, daring me to start to take it apart. Would it ever look as complete as this again?

I took another deep breath and picked up my Spear and Jackson tenon saw.

The die was cast.

Why did I reach for a saw instead of a spanner? Had the pressure been too much?

Would the gearbox ever come to bits? Would it go back together again? Would I be able to peen my flying balls?

All will be revealed in the next breathtaking episode of A BOX FULL OF NEUTRALS
Jake Wilson, Paignton

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