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Old 05-08-2019, 10:46 AM   #1
ryanheacox
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Default Pressure plate finger tolerance

What would be considered an acceptable tolerance when adjusting pressure plate fingers? I had suspected something was off when reassembling everything after putting the new engine in and recently the clutch started to chatter. Turns out none of the adjusting nuts were staked and all of the fingers were around 3/16”-1/4” … way off the 11/16” that they should be. The kicker is the note that came with the pressure plate said “DO NOT ADJUST” …

Anyway, I made up a tool to gauge the depth, was shooting for 11/16 (.6875). The tool came in at 0.692, not bad. I have a couple fingers adjusted to 0.692+0.004-0.000. Is that close enough or should I aim for a tighter tolerance like 0.002?
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Old 05-08-2019, 02:01 PM   #2
Patrick L.
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Default Re: Pressure plate finger tolerance

The spec is .002". Its not too hard to get with the unit on a bench but is tricky when in the vehicle so its my opinion that the .002" is more of a guide line in that situation.

I just turn a piece of stock to the dimension I want and then make the adjustment so each arm has the same drag. Then I tap each arm a few times gently and check/adjust them again. This is when the thing is on a bench.

When in the vehicle I just check for the tight arm and use a long .0015" feeler strip and adjust the rest to a fairly tight drag.

I'm kinda of the opinion that a chatter can come from a few issues.
Oil/grease where it shouldn't be but I don't see that very often
Finger adjustment
flywheel issue
bellhousing/clutch cover alignment
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Old 05-08-2019, 03:11 PM   #3
Kurt in NJ
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Default Re: Pressure plate finger tolerance

Push in the clutch and rotate the disc 1/2 turn and recheck, if you have a disc thickness variation problem all the figures will change
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Old 05-08-2019, 03:22 PM   #4
ryanheacox
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Default Re: Pressure plate finger tolerance

Quote:
Originally Posted by Kurt in NJ View Post
Push in the clutch and rotate the disc 1/2 turn and recheck, if you have a disc thickness variation problem all the figures will change

What's the easiest way to do that?
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Old 05-09-2019, 08:26 AM   #5
ryanheacox
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Default Re: Pressure plate finger tolerance

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Got it all buttoned up last night and boy is the clutch smooth again. Patrick, I do see what you mean about the 0.002 being more of a guide line in the car... tried to be a consistent as I could but between variations in holding the gauge I'm probably closer to +/-.004 but the clutch is smooth and I'm happy.

Went with the full belt and suspenders routine (nuts staked and loctited), let's see em back off now.
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