corellian vette

Greetings everyone!

Well I took the plunge and got my first 928 tonight. Its and '86 928s with about 91K on it.

I took a gamble because it has one significant problem - shifting the car into R or 1 is basically impossible.

Now, I got a bunch of money off the car for this problem, but now it's mine to solve.

Here are the specifics.

- Apparently it has an aftermarket short-shifter on it. I pulled the shift **** to uncover the **** which is properly attached and free of debris or blockage.
- When the car is shut off, it shifts through the gears smoothly.
- When I start the car, it takes the force of Hercules to get it into R or 1, if I can be done at all. 2-3 is OK, and 4-5 is very easy. SOMETIMES if I'm lucky when I'm rolling to stop I can get it to slip into 1st.
- There is NO grinding of the transmission at all. It just physically will not go in.
- Once the car is going, 2-3, 3-4 and 4-5 shifts are awesome.
- The clutch pedal release is a little higher than on my 924. I would not say it's at the top but definitely mid-pedal travel. Clutch engagement is smooth (no chatter) except when I have to take off in 2nd which was a lot.

I don't know this car yet and did not have a chance to get it on a lift tonight (I just got it this evening!).

It doesn't *feel* like a transmission or clutch release issue it *feels* like an adjustment issue. The PO mentioned something about couplers that need to be adjusted?

So that's problem #1 I have to solve before I can enjoy the car.

Anyway I'm hoping for some leads on diagnosis or tips on adjustments before i get it in the air to take a look.

Thanks in advance!

hb253

Two likely scenarios:

1. You need to adjust the shift coupler located near the transmission
2. The bushings on that shift coupler may be worn and need to be replaced

Hugo

Cosmo Kramer

+1 on the adjustment. I put in a Lizard shifter and the coupler needs to be bang on. One spline off one way or the other and either the R-1 or 4-5 are difficult to get in.

medipedicman

Old vs new bushings








The nut and bolt are your first place to start.

After loosening the nut the forward shaft should rotate independently from the rear shaft that goes into the trans. If you move the shifter very slightly towards the passenger side, then tighten up the nut on the bolt and you are ready for a test drive. Some folks will put the gear selector and the trans in 2nd gear before touching the nut and bolt or the grub screw. That makes sense but I have always had good luck with using neutral. Don't be afraid of making a mistake. The first time I did this job I over corrected and lost 4th and 5th, lol. Small, subtle adjustments are best.

GlenL

I'm doubtful that this is a linkage problem. It would be better than being internal. Problems with 1 and R when stationary can be from a dragging clutch and the synchos just don't allow a sync.

Best hope: Try to get more action from that rear coupler when pulling to the left.

mark kibort

sounds like classic intermediate plate issues. very easy to fix if that is the case with an adjustment

mark kibort

the 86's has the dual disc clutch system Glen,
so the problem is in my opinion, 100% due to intermediate plate being out of adjustment.
the fact that the OP can get it into all gears when the engine is off , should be the first clue. Then, has a real hard time in 1st and R, but all other gears are easy.. also another clue......... (this is because the synchros have more bit (torque) to speed up the driveline and mesh the shift)
so, an easy check is to see if the driveline is still spinning when the clutch is in. if so, then there is your problem.. clutch is not releasing the driveline.
if the driveline is stopped, there should be no probelm as was seeen with his example of "NO ISSUES" when engine is off. engine off= driveline stopped .

However when rolling, i was wondering if going to 1st is easier and possible. that is the final clue and answer

GlenL

My bad...

Check that dragging intermediate plate. Search is your friend here. Many, many (many, many) posts on the issues.

First shot: bleed the clutch slave. A bit more opening action may help and it's a lot easier than futzing with the clutch adjustments.

mark kibort

wow, even you can make a mistake?
I dont think its bleeding clutch, especially since the release he says is "high vs the 944 " that cover is easy to drop and maybe im not 100% sure that is the problem, but more like 90%.

corellian vette

Thanks guys! SO much information but a little bit of short hand for me to follow. So a couple follow-up comments (and I will do some search).

Mark just to clarify (with the car running)
R - 1 are nearly impossible. 2-3 are hard but doable. 4-5 are easy all the time.

The car rolling does not seem to matter much. (another reason I was assuming linkage). I would say I have nearly the same chance of getting into 1st whether the car is rolling or stopped.

Sounds like check #1 is to see if the clutch is dragging.

Step #2 is to check the coupler adjustment. Is there a good procedure for this somewhere?

Step #3 is to check the intermediate plate? Same - is there a good procedure?

If those are the right steps I'll also do some searching.

One more question - why does installing a short shifter make this problem worse? Would this get better buy just putting the stock shifter back in?

Thanks so much guys! Getting this fixed is key to enjoying the car I just bought.

Petza914

If it turns out your issue is in the rear shifter coupling, I have an upgraded 928 Motorsports one that's virtually brand new available for $125 shipped. It's around $185 new plus shipping. I removed it when changing to the z06 6-speed gearbox.

Good luck with resolving your issue.

GlenL

I think the linkage is a red herring here.

I suggest bleeding because it's easy even if it's less likely to fix the problem.

There's an adjustment on the intermediate plate that holds it away from the two friction discs. Picture a Big Mac with the flywheel being the bottom bun, the pressure plate being the top and the intermediate plate being the slice of bun in the middle. The discs are the meat.

Many pages devoted to problems and solutions. Read them...and try the bleed.

mark kibort

We can walk you through it.
toss out all the first sets of advice, because if you can select gears with the engine off, its not a linkage problem. Be happy you got the car for a lot of discount, because it will be easy to fix.

the reason that you cant get it in 1st even rolling is the RPM differnet vs speed of the car. try a blip downshift to first from 2nd driving down the street.

the short shifter installation has no bearing on the issue, ONLY if what you say is true. "no problem slecting gears with the engine off"

1. yes. check to see if driveline is still rotating with clutch in. you can see this under the car with the clutch pushed in.
2. if so, then its clutch int plate adjsutemnt. drop clutch lower cover and adjust int plate. take pictures of the gap at the H adjusters before you adjust them. i want to see.
3. linkage or coupler, is not the issue if you can select all gears with car engine off. ive had that problem before. the coupler can be off and not allow you to go far enough to one side or the other. this is a centering issue, and is obvious. quick test : if puting the car in 2nd gear puts the shifter in line with the digital clock... the shifter is oriented correctly and nothing should be blocking its travel.

mark kibort

good description of the twin disc clutch .. "big mac".

one more thing, if you can get the car in to 2nd gear with it running, do this test.. try and immediately put the car in 1st with no delay. (got to work fast as you need to get it to select 1st gear before the friction discs spin up the driveline as you pass through neutral.

the main point here is, if you can select all gears while engine is off, there is nothing wrong with the linkage. the side bet here is that the system needs bleeding, but thats a long shot.

also, building on the big mac analogy............... think of the int plate, as the center bun as Glen says. when the pressure plate (top bun) is pulled off the hamburger, the middle bun is sill forcing the lower hamburger to the bottom bun (flywheel). the adjustment of the int plate, allows the middle bun to pull up to release the lower hamburger (front disc) from dragging on the flywheel. (bottom bun). the hamburgers, (discs) are directly tied to the driveline, always!

its an easy fix. all you need to do is drop the cover and adjust the (3) H adjusters to have 1mm gap. (you rotate the engine around with a crank bolt socket ) i would bet now they are about 1.5mm. close them down with a large flat head screwdriver as a lever on the surrounding structure and they move very easilly.

corellian vette

Really, gents, thank you SO much. I have some searches to do but it sounds like there are a couple clear things to look for.

Just to be clear on one point, Mark. In your intermediate plate adjustment assumption, that WOULD make the driveshaft move when the car's in neutral, correct?

So step #1 is put the car on the lift, start the engine, put the shifter in neutral and see if the driveshaft is moving. If so, then check the intermediate plate adjustment and hope for the best!