At 08:21 AM 8/2/99 -0700, you wrote:
>"James E. Pickard" wrote:
>
>> We're going to pull the transmission and replace the gears with a wide
>> ratio set and then restore the rear end to the original 2.88. The
>> question is: can you do this without pulling the engine? We are
>> planning on overhauling the clutch while we are in there. Again, do you
>> have to pull the engine?
>
>>>Jim Pickard
>>>B9473298
>
>Jim, I was considering the same 'operation' for a limited slip differential
>installation, and keeping the original 2:88 gears. At first, removing the
>entire
>rear axle looked like the only way, as the 'spare tire' well was very much
>in the
>way. At the very least the axles must be removed. However, in examining is
>further I have concluded that I could 'drop' the rear axle assembly by just
>undoing the rear spring hangers and letting the axle (firmly supported) rotate
>down along the radius of the front spring eye. Of course, there is a point
>where
>your tailpipes prevent further lowering (and make poor supports), so they
>must be
>removed if enough clearance is not obtained.
>
>Since I am only changing the carrier, I probably don't have to worry about
>re-shimming the input for proper mesh, as it is good know, and there would
>unlikely be any change with just a carrier change. In your case, you would
>probably have to remove the drive shaft to get at the yoke, seals and shim
>stack.
>
>I have NOT done this, so this is only a suggested possibility, not
>demonstrated by
>me. Maybe some has tried this?????
First let me point out that carriers and housings were machined to tolerances
and originally lumped into compatible ranges from positive (+) to 0 to negative
(-). This was done to minimize the setup time for the gear fitting which was
done with shims below press fit components rather than adjustable mechanisms.
It could be hazardous to assume that a posi carrier was "interchangeable" with
a stock carrier without checking the actual measurements. When changing both
the Ring and Pinion, as Jim desired to do, requires a lot of measurements and
setup time. This is an operation I would discourage an amateur from attempting
at all, and "in the car" would be to invite major problems. Jim didn't say,
but I suspect that his intent was to reinstall a set of "used" gears. One of
the hard lessons I've learned is that used gears are frequently very noisy when
re-installed. New gears have an allowance and wear-in to their final
settings. Attempting to re-establish this original "setting" is very very
difficult. You can certainly get the gears to "work" effectively but the
"whine" is something you have to learn to live with. I've gone so far as to
sandblast (not in the car) the gear teeth to create a new mating surface. It
still took years before the whine subsided.
My recomendation - Pull the whole rearend and take it so someone with the
tools and experience to set it up correctly. They will likely guarentee their
work if they get to install new gears and bearings. If not, be prepaired to
live with some level of gear noise from the back of the car.
>On the clutch, you can definitely change the clutch, flywheel, transmission,
>bell
>housing pieces without removing the engine. It does require support to the
>block. You do NOT have to drill holes in your firewall. The upper two tranny
>bolts can be removed with a wobbly-extension / socket (NOT A UNIVERSAL JOINT).
>The other bolts can be reached normally. The transmission will also have
>to be
>disconnected from the bell housing, and a shortened length 'cut-off'
>combination
>wrench or a 'stubby' will do that job. The Rear transmission motor mount must
>also be removed. Better have some help here, or a very good transmission
>jack, as
>that thing weighs about 140 lbs.
Don't forget to remove the shift linkage. The bellhousing and transmission
come out together rotating in opposite directions to create the clearance.
This is not a job for people with back problems. Have a go at it, its been
done lots of times. Next time try pulling the front end and dropping the
engine and tranny as a unit. After you've done it both ways, I think you'll
opt to pull the engine and tranny rather than fight the less than optimal
clearances. You'll need to create the various plugs for the output shaft and
the Speedo hole to prevent an oil mess, and similiar plugs for the engine.
After some practice, you can pull the front end, and the engine-tranny assembly
and reinstall it all by yourself.
Tom Hall
|