This can't be good - oil in shift coupling boot

cak · 02-24-2007, 06:51 PM

I've got the bushing kit. I'm not quite ready to do the install, but since I was fiddling in the back seat area today, I pulled the cover.

When I move the shift lever, I see pretty direct motion of the shaft going into the boot. OK, the coupler bushings must be worn. I pull back the boot and ... hmm, this can't be good, why is there visible fluid in the bottom of the boot?

OK, yes, the bushings there must be pretty shot, lots of dead motion. The fluid is gear oil. (It's not blue, so it must not be Swepco, add that to the list.)

I'm guessing that there's a perished seal where the shift rod goes into the transmission, and there's oil coming out when I jack the car at the rear.

How much do I need to worry about this?

When I take the coupler out, what's the critical alignment that I need to mark? The spline engagement and depth, or the attachment to the transmission?

Early_S_Man · 02-24-2007, 07:08 PM

Chris,

Here is an article showing the seal replacement:

http://www.pelicanparts.com/techarticles/mult_shifter_rod_seal/mult_shifter_rod_seal.htm

The recess for the set screw fixes coupler and trans. shift rod orientation. Mark the spline alignment and depth of rod 'cover-up' ... to re-establish your baseline setting.

cak · 02-24-2007, 10:13 PM

Thanks Warren ... what fun! Should I worry about this, or do it when I get there?

KNS · 02-25-2007, 05:04 AM

I found the same thing...Is this a problem ??

Early_S_Man · 02-25-2007, 05:12 AM

It is not a big problem ... until you find gear oil sloshing in the tunnel. By then, I think, passengers will be asking how many dinosaurs died down there!

KNS · 02-25-2007, 07:21 AM

Thanks Warren.

Jim Sims · 02-25-2007, 09:30 AM

Make sure the leak hasn't lowered the transmission oil level to the point the fifth gear components are no longer getting oil.

cak · 02-25-2007, 09:52 AM

Quote:

Make sure the leak hasn't lowered the transmission oil level to the point the fifth gear components are no longer getting oil.

OK. Seems unlikely, since it was only about 2 fl oz of liquid, completely contained in the lower portion of the boot. Only took a couple of blue paper towels to sop up.

Johnb911 · 02-25-2007, 09:56 AM

THE TOOL

I used a set of SNAP ON Pics.
They are about 30.00 for a set of four.
They have all diiferent kind ends on them.

i struggled with mine untill I finaaly got between the seal and the sfaft tube, slid past the seal and hooked it. Then pulled.

just a tip.
When you are ready to go.

Oh ya.

Take out the seats .
It's 10 minutes but not 1 hour of frustration.

cak · 02-25-2007, 10:05 AM

Thanks for the tip. Yes, I have some new seats on the way, and I was going to do the coupler bushings and some under dash electrics while the seats are out ... guess I'll add this to the list.

cak · 10:34 AM

OK, I did the coupler bushings and the shift rod seal. The boots were completely oil soaked, so I decided to splurge and buy new ones instead of cleaning up the old ones.

There was a delay in getting them, so I was driving w/o ... long enough that I no longer have a good mental image of how they fit!

Getting the "rear" one on was straightforward with a little silicone spray on the part that goes over the nose of the tranny. I could do that by just removing the conical set screw.

The front one required removing the pinch clamp. Oh well, I marked carefully and seem to have gotten the adjustment back where it was. But ... how do the two fit together? Is the bellows that's over the shift bushing supposed to fit around the "rear" boot where it is around the retaining ring? That seems like the only sensible choice, but it wasn't easy!

It's certainly a snug seal - I can hear air being sucked in through the slot in the shifter shaft when going from first to second.

Now ... about the coupling adjustment. At least one article indicates that there "must be slight rotational play at the coupler" in 5th gear. Is that true for this vintage 915? The coupler can be moved just more than imperceptibly, but not nearly as much as in the other four forward gears. It feels like it is stiffly held by the spring at the shift lever.

Thanks.

Gunter · Gunter's Garage

Chris:
The final adjustment of the coupler is very delicate.
It takes MINUTE amounts of movement on the clamp to get it right.
Mark the position and try SMALL adjustments.

cak · 11:29 AM

Quote:

The final adjustment of the coupler is very delicate.

OK ... but should I expect to have as much play in fifth as I do in first through fourth? I'm not sure what I'm going for.

(And where's the play come from, anyway, if the shift lever is locked in place and I'm using the non-oval coupler bushings?)

cak · 04-19-2007, 01:49 PM

OK, it took about four tries, but I got it.

As has often been the case, Randy helped me out with his commentary, in this thread:

fine tuning shift coupler

The trick for me was to put it in fifth, loosen the pinch bolt, and tweak the coupling (with padded ChanneLocks, I couldn't easily move it by hand) until I had a little play. Then tighten.

To answer my own question, it's not as much play as in 1-4, probably because that play includes slop in the shift lever cup bushing (that's on my list). I'd guess it's about 1 spline line on the coupler's nose shaft.

The real pain was putting the boot back on! Maybe the Factory Schule teaches how to shrink your hands, but I couldn't get to the bottom. I finally figured out to roll back about 1/2" of the boot all the way around, align it with the other boot, and then roll over. There was some twisting of the combined boots and final aligning, but this worked OK. (Glad I put silicone on the surface that contacts the tranny, so the inner boot spins freely.)

Gunter · Gunter's Garage

Chris:
The real test comes with shifting while driving.

It happens a lot that Reverse is nicked when coming out of 5th.

Most people concentrate on the radial adjustment of the coupler and forget about axial.

If all comonents are good, it is possible to get it just right with minute adjustments.
I leave the tunnel open, take the Allen key along; go for a drive and adjust as I go.

cak · 04-20-2007, 08:37 AM

Quote:

The real test comes with shifting while driving.

Yah, I hear that. Can't drive it until I replace the broken throttle pedal... thanks for your help.

Mike Andrew · 04-20-2007, 08:58 AM

Gunter;
What is the fix for the reverse nicking when coming out of 5th? Is it a front to back adjustment? if so, is the problem caused by being too far forward or too far back?

Gunter · Gunter's Garage

PROVIDED that ALL bushings and mechanical parts are good, it's a matter of adjusting; VERY small amounts.
The clamp on the shift rod has to sit in the middle of the range: axial between 1-2, 3-4, 5-Reverse, plus radial with the prescribed procedure and still have a small radial movement in the coupler when in 5th.
I would take a close look at the pawl in the shift tower that is supposed to prevent nicking reverse.
If it is mechanically sound, use some lube on it and other components in the mechanism. The play in the center can be adjusted if you have the large nut sticking out in front of the shift tower.