Hi Scott, please see my answers below.
Bob
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> From: Scott Allen <s4usea@hotmail.com>
> To: mg-t@autox.team.net
> Subject: TD Transmission Problems
> Date: Tuesday, August 24, 1999 7:03 PM
>
>
>
> All,
>
> So I thought I was done restoring my '52 TD, but much to my
> chagrin when I took it out for its first drive last Saturday
> I ran into a problem.
>
> Last February I had purchased a re-built transmission from a
> gentleman from San Francisco, and I installed it in April, but
> wasn't able to try it out 'till last Saturday. When I did, I
> heard a loud thumping coming from the bell housing in whatever
> gear I was in. So, a friend and I pulled the transmission
> over the last few days, and cast a more critical eye on it then
> when we originally installed it. In any event, I now have several
> questions that I hope someone can help me with:
>
> 1) The pressure plate is rubbing up against the bell housing where
> the bell housing is cast to accept the pin that holds the release
> bearing fork, (on both sides). This didn't happen with the
> old transmission, and the pressure plate and flywheel is not loose. Any
> ideas what can be happening here? Do they make different
> height pressure plates or bell housings for TD's?
YES,
You probably bought a 7 1/4' clutch bell housing and you have an 8" clutch.
Some serious grinding away of the 7 1/4" bell housing clutch cross shaft
bosses will solve the problem. Better yet, just swap the bell housings and
use your original 8" one on the "rebuilt' transmission. 7 1/4" bell
housings have a 5/8" clutch cross shaft, 8" bell housings have a 3/4"
clutch cross shaft.
>
> 2) The spline has approximately 1/8" side to side play in it.
> Is this normal?
NO, some play will be present, but 1/8" sounds on the high side. If the
needle rollers at the rear of the first motion shaft ( clutch shaft ) were
not replaced, some excess play may be evident. Also, the front ball bearing
may have too much play. In any case, the crankshaft bush must be new and a
nice snug fit on the first motion shaft . This will help support the first
motion shaft and probably you could live with the 1/8" play. New front ball
bearing and new input spigot roller needles should reduce the play.
>
> 3) In rotating the spline to turn the flange that connects to the
> driveshaft; every two turns it sticks a bit. It does this in
> every gear, and while you can still turn the spline it's obvious
> that it's grabbing somewhere inside the transmission. I don't think
> this is normal, so does anyone have any ideas what can be causing
> it?
Tough call from afar, but since its regular and in the same place, I would
suspect the laygear is hanging up on one of either, input gear from first
motion shaft, or third gear or second gear. Possibly one of these gear sets
has a slight imperfection and causes the gears to "stick'. I would strip
the box and check EVERYTHING. Look for a burred gear tooth?
>
> 4) Lastly, but related, I had to pull the pressure plate off to make
> sure the flywheel bolts were tight, and I can't find torque specs
> for either the flywheel or pressure plate bolts. Any ideas
> here?
Flywheel is 50 ft-lbs.
Clutch pressure plate mounting bolts torque is 20 to 25 ft-lbs, depending
on how new and what grade bolts are being used. If you have the original
bolts, I would go 20 to 22 ft-lbs and Loctite the bolts on assembly. New
grade 8.8 bolts can tolerate 25 ft-lbs. Of course bolt size is 8.0 x 1.0
mm.
Some sources will say 29 to 32 ft-lbs, but these are too high and you face
a real danger of shearing a bolt if you go to these higher torques.
Check or replace ( not forgetting to pre-oil ) the oilite bush in the end
of the crank while the clutch is off to ensure it is a nice snug fit to the
input shaft spigot.
> That's it. I'll keep everybody updated with what I find.
Thanks, I'd like to know what you find.
regards, Bob Grunau
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