924Board.org

[Chrenan]

Alright, had my car on the road last night with the new engine. For the most part everything went well ( http://www.924board.org/viewtopic.php?p=156549#156549 ).

However, I think I have a clutch issue. When the engine went in, I installed a new clutch disk, pressure plate, thowout bearing and clutch cable. Here are the symptoms:

1. Push clutch pedal in, all is OK.
2. Move gear lever to 1st, all is OK.
3. Let clutch out to get car rolling, grinding noise, whirring noise, car lurches forward a bit, then not, then lurches, then grinding, more whirring, apply more gas, feather the clutch, car almost stalls, finally the car gets moving, once moving and into higher rpm in first all is OK, car runs smoothly.
4. Shifting into 2nd, 3rd, 4th, 5th, all is OK, smooth and no protesting.
5. In a low speed roll from second, when releasing the clutch, I get the same issues I get in first.

Could this be a clutch cable adjustment issue? I used a caliper to measure out the 138 mm in the picture below, I am fairly certain I got it within the +-2mm. However, I'm not convinced I have 20 to 25 mm of free play at the pedal, how do I get this? Feels like as soon as I step on the pedal, I am moving the throwout bearing.

Any ideas? Does it sound like a clutch cable adjustment issue?


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1987 951 - M193 Version for Japan

[Ozzie]

The adjustment is without the free play- ie someone has there foot slightly on the pedal.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

[Chrenan]

Hmmm, I think I made a mistake then.

With nobody touching the pedal, I have 138 mm as in the picture above, that is definitely wrong.

Does that mean, with nobody touching the pedal, the distance measured out in the picture should really be 158 mm? Is the fix that easy?




Got lots of good info from this thread as well:

http://www.924board.org/viewtopic.php?t=12258&highlight=clutch+cable+replacement+help
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1987 951 - M193 Version for Japan

[Ozzie]

Don't know the exact measurement but it will be more than 138mm.
Just ease off on the adjustment untill you get 20mm travel on the pedal till you take up the slack.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

[Mike924]

The Haynes manual is particularly bad at explaining this adjustment.

The 138 mm figure really has nothing to do with the cable adjustment. It's to place the the lever arm in the correct position for the cable when all the play has been taken out of the bottom end of the works (i.e. clutch plates, thrust bearing, etc).

Once this dimension is correctly set, the cable can be installed and the cable adjusted soley for the free play at the pedal. If the lever isn't set correctly to start with and you use the cable adjustment to obtain the 138 mm, the clutch will slip and wear prematurely.
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1985 Porsche 924 'Lux', Kalahari Beige (my ex)
1993 Porsche 968 Coupe, Midnight Blue, 6 spd

'There is no substitute for a little grease under your fingernails.' - Chrenan, 924board.org

[Chrenan]

Thanks for clearing that up Mike, that is exactly the problem I have at the moment. I basically tightened everything up to 138 mm so I have zero slack. You're right, it is horribly explained in haynes, at the very least they should have drawn a foot on the clutch pedal in their diagram to signify the freeplay had been taken out of the works to meaure the 138 mm spacing!
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1987 951 - M193 Version for Japan

[Mike924]

[gohim]

You are making this way more complicated than it has to be.

Loosen the adjustment locknuts clutch cable housing.

Pull up gently on the clutch housing to take the slack out of the cable. Make sure that the lower locknut is not in contact with the mounting bracket when the slack has been removed.

Now look at the distance between the top of the cable stop/mounting bracket and the locknut.

You should see about a 1/4" of space. If you see less, turn the upper locknut up higher on the cable housing threads until you get the 1/4" of clearance.

When you have the clearance, release the cable housing and hold the cable housing and the upper locknut in place while tightening the lower locknut.

This procedure takes about two minutes.

This simple procedure can be used on most any German made car with a cable operated clutch. Just look for the adjustment on the clutch cable housing the the bracket, then set up the 1/4" of clearance. Works every time.

[Chrenan]

Gohim, thanks for the explanation, it is very clear, even better than the one you gave to Timstar in the linked thread above.

I will try your 1/4 inch technique on Friday and see how it goes. I got everything loosened off last night, and you're right, it should only take a few minutes to set everything using your approach. I took off the inspection cover on the bell housing, and it doesn't look like I damaged anything on my brief drive with a poorly adjusted clutch cable, fingers crossed.

Note: 1/4 inch = 6.35 mm if anyone reading likes to use metric.
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1987 951 - M193 Version for Japan

[PORSCHEV]

I put a clutch in backwards once that made similar problems..good news is...if you do it wrong once...you NEVER forget to double check after that!
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1976 924
5 lug conversion, 17'C2 wheels,custom body work,327 vette engine.

1978-#53 "D" track racer.

[Chrenan]

Hmmm, I hope I didn't do that. I was very carefull about putting it in exactly as the old one came out (which worked fine and matched to the factory manuals). The old one coming out and the new one going in was seperated by a few minutes, so I think I got it correct. I even left the layout of the old clutch assembly on the ground beside me so that I could assemble the new parts in the exact same manner. Of course, now that you mention it, I will worry about it!
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1987 951 - M193 Version for Japan

[Meneer aard]

I have a question to about the clutch....

When i use my clutch pedal i need to push him right to the bottom of the floor? I have a free play of 20-25 mm but the car starts to roll when the clutch pedal is about just from the floor with the clutch pedal???

Must I adjust the clutch? The haynes manual talks about the inspection of the clutch under the car, but what`s the right order to adjust the clutch? (i have never done it before)
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Porsche 924 Euro 1977

[PORSCHEV]

Chrenan..I just find it strange your getting noises when engaging the clutch. Can you tell me if the noises are coming from the clutch area..or tranny area??

Also..how bad is it to shift into reverse?

Let us know what happens after you get it adjusted.

Sorry to make ya worry...been there done that...it sucks!
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1976 924
5 lug conversion, 17'C2 wheels,custom body work,327 vette engine.

1978-#53 "D" track racer.

[Chrenan]

Noises when letting the clutch out (foot coming off pedal), and definitely noise coming from the clutch area, but also grinding at the tranny.
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1987 951 - M193 Version for Japan

[torro]

You should be very unlucky if you manage to install the clutch the wrong way.

I was a bit puzzled about the release bearing, the bearing had gone loose when I removed the engine from my car and was dangling on the guide, hanging in a way that made in impossible to tell which way it should be, whether the springs should point upward or down. The Sachs inscription and the most logical way were downward, and I installed it that way. I have not yet tried to start my newly rebuild engine, and I am a bit worried if this will make any difference....

This is the bearing I have installed, and the direction I installed it.




In the manual there is a bit different release bearing, and the springs seemes to point upward...

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-=Torro=-