Logic check please_gear selection problem

I would agree with you, the input shaft has to be turning with clutch pedal depressed. Any possibility you fitted the friction plate backwards? ( though if this was the case I would expect some noticeable noise especially when the clutch is slipping) Failing that I would be suspecting a cracked / faulty pressure plate diaphragm ( which would give the symptoms you describe, but unlikely for a new part ) or a faulty pilot bearing.


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Pull it all out again and have a look. If the pilot bearing is seized, it'll make a hell of a noise (ask me how I know), but the clutch shouldn't slip. My guess is there's something fundamental that will become obvious when you pull it down. Sorry, sometimes it's just easier to start again.

 

One test that you can do (that probably won't change that you'll need to redo based on your description) is to put the car into 1st gear with the engine not running, clutch pedal depressed, and crank the starter motor -- if the coachwork lurches forward = no/poor clutch disengagement (but you need to be sure that you've got enough space for safety in front for motion and the possibility the engine could start).

 

Where did you get the parts? Unfortunately, not all parts sent are as described even from the best vendors, I've learned.

 

Also, the friction disc has a correct and incorrect directional orientation. If you put it on backwards, it won't engage properly, and then overadjusting the clutch cable to compensate would just worsen things. Another possibility could be you didn't properly slip the forks on the output shaft in the bell housing under the retaining rings for the throwout bearing carrier, in which case pumping the clutch pedal won't necessarily actuate the clutch.

 

i have a similar although not identical problem.
new clutch, t/o bearing, pilot bearing, rear main seal. also flywheel turned.
my guy complained the friction disc looked aftermarket. i instructed to install anyway.
now the clutch chatters significantly and will not engage smoothly. clutch has to be slipped to get underway.
i complained to vendor who replied they've never sold an inferior clutch. would not comment further.
am i in for another clutch?
comments please.

 

If you turned the flywheel and now have chatters, then you need a different clutch disc. How was the pressure plate/

 

i forgot to mention, the pressure plate was changed as well.
different clutch disc? perhaps this is why my tech questioned its quality before assembly.

 

I stopped buying non-OEM clutch discs after one "rebuilt" one blew up, stranded my friend, and I had to redo the job... Not worth the $200 saving.

 

My immediate thought would be that the flywheel is not running true to the crankshaft or been machined not square. Out of interest are the marks on the flywheel 180 degrees opposite to where they are on the pressure plate , if you can recall the orientation of the pressure plate to the flywheel before it was unbolted ?


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But if the friction plate had the wobble then it would make a continuous mark around the flywheel/ pressure plate. The only way I can think of getting a single hotspot would be if the bell housing is mounted square to the block, the input shaft is running true into the back of the crank is for the flywheel/pressure plate assembly to be running out of true, mind you I’ve just had an hour of learning German so my brain is partially fried


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If the flywheel was not machined true to the crank mounting flange then the assembly would wobble but the pressure plate and flywheel would still be parallel to each other. This damage looks like there is uneven pressure on the disc around the circumference of the pressure plate. As stated above, I think, if it was a disc problem the clutch may have disengagement problems but the wear marks would be consistent around the pressure plate.
I vote for either an un-true surface on the pressure plate(least likely), a bad pressure plate diaphragm spring, or a problem with the throw-out bearing assembly causing it to not press on the pressure plate evenly. Or possibly the pressure plate did not seat evenly on the flywheel due to interference trouble with one or more of the locating pins or a similar problem.

 

Hi Andrew, Sorry to see this as it looks like your new pressure plate was not parallel or was not lifting evenly (as suggested by tomberlin above.) I would start by checking the T/O bearing is straight and all the way onto its carrier, check the diaphragm spring and see if there is any obvious sign of something wrong or misaligned, and put a straight edge across the PP mounting face and check the gaps to the pressure surface all the way around. Check the disk thickness as I think there was some discussion a while back about some aftermarket disks being too thick (and some aftermarket PP not lifting correctly.) A clutch shop can easily check the PP for you.

I just had my original PP ground a smidge to give the newly rebuilt disk (with tribco kevlar) a suitable surface and the clutch shop tested it and said the diaphragm was still fine. Rebuilding the originals (36k miles) cost the same or slightly less than a cheap aftermarket kit.

 

Glad you found the problem. Their parts are inexpensive and they are very good about returns. That business model suits us DIYers but can be frustrating at times. Do you have a clutch shop near you? Get them to check your old PP, might be fine or just need a light regrind.

 

AW Italian in New Jersey Has both competitive prices and correct parts. They are a regular DIYer and pro shop supplier when it comes to "major service" items and kits.

 

How were you measuring the pressure plate face? I don't doubt what you're saying just curious of the method.