901 clutch problem, HELP!

911-m5 · 09-19-2004, 11:46 AM

The motor and tranny have been out of r a year on my '70 911T. I just put everything back in and I can't get the clutch cable adjusted. So, I realize that if I put the car in gear with no clutch cable attached, I shouldn't be able to move the wheels - but I can move the wheels. Now, I'm thinking there is something really wrong. I look at the clutch fork and it is at rest with most of the space in the tranny case showing towards the back of the car and very little towrds the front. I tried to move it in both directions, but it will only move towards the front of the car and then it actually hits the tranny case. I am thinking it should have more travel and that it should be at rest closer to the back of the hole in the tranny case. Anybody have a clue? If you tell me I have to remove the engine and tranny again, I am going to cry.

Thanks,
Allan

john walker's workshop · 09-19-2004, 12:51 PM

when the trans is slipped onto the engine, on a 70/71, the ears on the t/o bearing are aligned so they are on the same plane as the LENGTH of the fork. when the trans is bolted up tight, the fork is pulled past the t/o bearing, ( fork part moves towards the pressure plate), then the bearing is turned 90° with a screwdriver, so that the ears are captured under the fork tips. if that wasn't done, you will at least have to lower the engine/trans so you can attack it thru the hole on top of the bellhusing.

Grady Clay · 09-19-2004, 03:06 PM

Read these two threads:
’70-’71 clutch
clutch cable for 70-71 901
and
'70-71 T.O. arm play?

This may give you some insight.

Best,
Grady

911-m5 · 09-19-2004, 03:21 PM

Thing is that I never took the two totally apart. I did take the bolts out that mate the engine and transmission together, but because they are rather difficult to separate I never did. So, there was a gap between the two but only about half an inch or so. All this stuff still apply?

Grady Clay · 09-19-2004, 04:25 PM

Allan,

Are you saying the engine and transmission are back in the 911 with about ½ inch between the engine crankcase and the transmission bell housing?

Don’t cry, you want this finished properly. We all make mistakes and that is not a problem. This Pelican Forum is here to help you toward a solution.

Here are some questions for you to answer the best you can:

1. Is there still a gap between the engine and transmission?

2. If so, how much?

3. Describe the position of the clutch arm in the transmission opening.

4. Are all four engine and transmission to chassis mounting bolts in place?

5. How well did they fit?

6. Describe anything that you feel is a problem.

We are here to help you.

Best,
Grady

911-m5 · 09-19-2004, 06:52 PM

Everything is in place. No, there isn't a gap now. Everything is how it should be ecept that I have too much clutch cable to adjust which I suspect is because the clutch fork cannot travel its full distance out. If I put the car in gear, I can still turn the rear wheels with my hand - I shouldn't be able to do this with the clutch cable not installed. So, I suspect it is the throw out bearing or pivot bushing or something inside the tranny housing which means I am going to have to take it all back out of the car. It really is demoralizing and frustrating. I haven't been able to drive the car for 1 1/2 years. Now, I get it all abck together and it runs good but I have to take it all back down for something stupid.

Randy Webb · 09-19-2004, 07:04 PM

IT's time for a beer. Relax, kick back and think about how close you are.

We've all been there ....

Grady Clay · 09-19-2004, 08:32 PM

Allan,

When you say you can turn the rear wheels by hand, describe the situation. If you turn one wheel does the other turn the opposite direction? That is normal with an open (non-LSD) differential.

Did you read the two threads that I linked above? With a Pelican search there is more.

Best,
Grady

911-m5 · 09-20-2004, 06:48 AM

Grady,
Yes to both of your questions. The other wheel turns the opposite direction. I did a search before I posted this and I have already seen those threads and a few others. Based upon what john walker said and some threads it seems I'll have to pull it out again.

john walker's workshop · 09-20-2004, 06:53 AM

if you never separated the trans from the engine, and never messed with the fork or t/o bearing, nothing should have changed. is the pivot bolt that goes thru the fork still whole? they commonly break, or even unscrew. the fork pulls on it as a pivot point when the clutch is operated.

Grady Clay · 09-20-2004, 07:15 AM

Allan,

OK, let’s think this through before you take anything apart.

Turning one wheel and having the other turn opposite only tells us you don’t have a LSD but nothing useful for this diagnosis.

With the 911 on the ground and in 4th or 5th gear, can you lightly push the car and have the engine turn?

You said the engine runs while the transmission is in neutral but no clutch cable. Any unusual noises? Is the clutch arm contacting the pressure plate?

With a flashlight, or better yet a micro light on the end of a wand, you can see past the clutch arm and see if the arm is engaging the clutch release (TO) bearing. Remember, the arm has to pull the bearing away from the flywheel. You can confirm the pivot is in place.

OK, on to the cable and hardware.
Can you get access to a digital camera and show us all the pieces you have?

Remember, the outer housing of the cable assembly (Bowden Tube) pushes on the clutch arm via the “plastic piece.”

Tell us what you see.

Best,
Grady

911-m5 · 09-20-2004, 08:54 AM

I talked to a local mechanic that I know. He suspects that the clutch fork has slipped out of place. I am first going to try a little prying to see if it will pop back in. I can't really give you any better details until I get back to the car (maybe tomorrow or this evening) - it sits in my girlfriends garage about 30 minutes away from my house. The mechanic is also letting me borrow his Porsche workshop manual, but i won't have that until tomorrow evening.

John - as I said I did take the bolts that hold the engine and tranny together, but I never got them more apart than the clips that hold the together would allow. This was my first Porsche engine removal and I was using Wayne's book which is based on removing an engine on an SC. It said I could take the engine out without removing the tranny. Little did i know that wasn't possible on my car until there had been a lot of tugging and some pressure put on the fork because at first I thought the engine and tranny were just bound up. So, i could have broken something like the pivot bolt and not known it.

Grady - I don't have the exhaust or air filter housing on it so it was really loud - sounded really good, too. I didn't here anything unusual.
I have all the pieces to the clutch cable - 2 thin walled nuts, the the round bit that goes on the end of the cable and the plastic piece that everybody says to replace with the aluminum alternative. The rest of your questions will have to be answered later when i am at the car.

Thanks for the help guys. I'll keep you posted.

john walker's workshop · 10:43 AM

so when you move the end ofthe fork toward the engine, it will contact the edge of the hole in bellhousing? if that's true, then something has parted company. like grady says, you should be able to see something with a flashlight from below, looking into the hole, but it may have to be lowered so you can work from the top of the bellhousing to see what's up. a mirror and flashlight help a lot.

911-m5 · 09-20-2004, 12:35 PM

Yes, if I push it towards the fron of the car, it will touch the bell housing. I have pretty much accepted the fact that it will have to come out again. It's like riding a bike - I'm sure it will go much faster the second time around. If it is that piot bushing will I have to take the tanny apart to fix it or can you do it throught the hole?

ckissick · 09-20-2004, 12:48 PM

I went through exactly the same thing with my '70 911E. First, I read Wayne's book on removing the tranny from the engine, and couldn't get them separated. I then found out on this forum about the fork/bearing issue. I turned the bearing and then it was easy.

When the new engine went in, I mated the engine and tranny and rotated the bearing and everything went well. Then after spending weeks trying to sort out the wiring and other issues in my spare time, it was finally time to run the engine for the first time for 20 minutes. Being impatient at this time, I fired it up without the clutch cable installed. It fired up and ran smooth for 15 minutes. Then, a fairly loud rattle started in the tranny. I shut it down and installed the clutch cable, and then I had pretty much the same symptoms as you.

I knew the bearing slipped out of place: I figure it worked its way out while I was running the engine. Like you, I was not relishing another engine drop. It had been 6 months, and I have very little spare time. So, I took it to an old friend, a p-car mechanic, and he had it sorted out in one day. It cost me more, but I'm driving the car now.

Charlie
1970 911E
1950 VW