Advice wanted re. TC transmission & rear axle ratio

[CFritz7001@aol.com]

Hello, All,
I'm preparing my '48 TC "Betsy" for a 4-month tour of her homeland. She has something over 200,000 miles on her original, untouched transmission. My concern is that the tranny is beginning to be somewhat noisy in top gear, most especially under light load, constant speed--level ground conditions (ie. neither accelerating nor coasting / deccelerating). It's not too noisy when under load or deccelerating in top gear, and reasonably quiet in the lower gears.

My questions are these:
1. Assuming that an overhaul of the tranny is indicated, which parts are the most likely to need replacement ?
2. After 46 years as Betsy's chief mechanic, I feel I'm reasonably proficient as a mechanic, but I have never unbuttoned a tranny. Am I biting off more than I can chew to attempt an overhaul on my own?
3. I'm seriously considering fitting a lower-ratio rear axle to get more relaxed cruising. Betsy's engine has been brought up to MK2 TD or TF specs., and has an over-bore of 40thou., and she's running 4.50x19" wheels. What ratio would be the best compromise?
***
Comment, suggestions?
Regards,
Carl Fritz

[Peter Pleitner]

Hi Carl,

I'll address the more or less external parts of the trans you should look at first. Take the rubber cover off and inspect the rear transmission cover for cracks while you are there.

As to that noise, it might be that approx. 16 inch long 9/16 inch or so diameter metal rod that is the remote selector which connects your shift lever to the transmission. It runs through and is supported by a hole in two bosses under the remote selector neck made of aluminum. Often these holes are worn allowing the remote selector rod to rattle. The old fix was to wrap a shop rag around the remote selector. When I rebuilt mine, I bushed these bosses and line reamed them, not easy I might add.

The other most likely wear (not destruction points) are the bearings on the output and lay shafts, the lay shaft itself and shim, shift forks and selector pin at the end of the remote selector. Almost all of these require disassembly, not difficult, just puzzling and necessitating some pullers. 200k miles would indicate to me bearing wear is present. But bearing failure usually announce themselves by a rumble under lead, not a rattle under no load. Anyway, there is a penny's worth of experience.

Cheers, Peter

[Gene Gillam]

Carl,

I don't think you're biting off too much.

I bought a TC to restore and I've tried to do as much as possible myself. My transmission had been open (and laying on a workbench) for six years before I bought the car. I managed to tear it down and put it back in running shape without a whole lot of trouble - and I have much less of a mechanical background than you do (Navy Electronics Technician for 30 years).

The only part I had trouble removing - and then finding a new one of - was the first motion shaft nut. It's a reverse thread and neither Moss nor Abingdon Motors had one at the time (showed in their inventory but turned out to be for the TD/TF transmission). Assume right off you're going to have to replace it and order one before you take yours off - and try it for fit before you trash your old one. As far as what to replace - naturally you'll want to replace the first motion shaft bearing, the first motion shaft oil seal, and the rear mainshaft bearing. The other parts to be replaced will really depend on how worn they are. If you haven't already done so in the past, you'll also want to replace your rear transmission mounts (they should be made of rubber mush by now).

I can't help you with the rear axle ratio.

Good luck to you -
Gene Gillam

[taterry@aol.com]

In a message dated 1/12/00 11:38:15 AM Pacific Standard Time, CFritz7001@aol.com writes:
i'm seriously considering fitting a lower-ratio rear axle to get more relaxed cruising. Betsy's engine has been brought up to MK2 TD or TF specs., and has an over-bore of 40thou., and she's running 4.50x19" wheels. What ratio would be the best compromise?

Carl, I'm like you, scared of gearboxes but the boys tell me they are a piece of cake, you just have to dive in. I'll comment on No. 3: If I were you, I would wait until I got Betsy home before changing your diff ratio. While in England try your best to stay off the Motorways and on the A and B roads, there you will find the original set up just perfect and the scenery is better too. While you are in England, you might consider buzzing by Roger Furneaux's and picking up a new ring and pinion gear set. Roger has had them remade in I think 4.6/1. I run a 4.55/1 Morris diff in my TA and find it works very well out here on the freeways. Rogers ratio is a good compromise and the Morris diffs are getting very hard to find.
Good Luck
Terry

[Jorolibb@aol.com]

Carl,

You might as well figure on replacing all the bearings and seals. As said before, look for a broken rear cover (aluminum) and worn selector rod bores in the remote. The thrust bearing and shims might as well be replaced while it is apart too. Do be careful when removing the nut on the input shaft, left hand thread as noted in another reply. When reassembling the lay shaft and needle bearings, have a dummy shaft made up, 3/4" if I remember right, that is just as long as the assembly, including the thrust bearings on either end. Lower this into the housing and then push it out with the new layshaft (these are always worn out). It is pretty straight forward of a box to rebuild and shouldn't be to much trouble.

Good wrenching,

John Libbert
TC 2138
J2 3118

[Viv James TraX Interconnect (Pty.) Ltd]

Carl,

Doesn't sound to me like Betsy's got any major problems with her gearbox. I would leave it well alone unless I was pulling it out for some other reason. If this was the case, I would do exactly what has been recommended by the other guys with regard to bearings etc.

In addition to the standard rattle from the gearshift. my TC2459 has a gentle hum from the back axle at about 50 mph under no load even after new bearings etc. so I just ignore it. However, the standard differential bearings are not known for longevity so maybe you should remove your diff centre section and check it out. Perhaps you should also check the outer wheel bearings as well.

By the way, I've ordered tapered 1/2 shafts from Roger Furneaux for both my TCs to eliminate certain worries from my life for ever (rear wheel play, oil leaks broken shafts etc.). I realize that this will draw remarks from my some of fans on the list but what the hell!

Viv James

[taterry@aol.com]

In a message dated 1/12/00 10:19:22 PM Pacific Standard Time, vivj@iafrica.com writes:
by the way, i've ordered tapered 1/2 shafts from roger furneaux for both my TCs to eliminate certain worries from my life for ever (rear wheel play, oil leaks broken shafts etc.). I realize that this will draw remarks from my some of fans on the list but what the hell!

I, for one. am restraining myself.......... :-)
Terry, ex-Luddite

[ROGER FURNEAUX]

This dummy is only used for a few seconds, and can very well be made of WOOD, either a thin broomstick or wooden dowel rod is easily obtainable. Cheaper and easier than metal!

For a quieter g/box, keep the end-float of the layshaft cluster to no more than 4 thou of an inch. This might mean making thicker than std. thrust brgs. I believe Phil Marino does these in the 'States, here in England Jerry Brown is your man.

ocTagonally
Roger Furneaux

[Ned EYLES]

Having spent years fixing it,,broke or not . Dont you remember the old days when you had a little less money and only mended it when it expired. Second hand parts,any old bodge up to save money. Your girls stocking, for a fan belt,, Copper nails ,to take up the slack twixt half shaft and hub, I once made the last 10 miles home with the bonnet up,,screen down,,and lady tapping on a reluctant fuel pump,, well it was very early in the morning, So i favour the go to england and relax. If it expires ,help is at hand. enjoy the visit. Just watched the Monte re run in Cannes