mystery pressure plate bits

jvandyke

jvandyke

True Classic
While inspecting my pressure plate these fell out, no idea what they are, I will investigate inside the PP more later tonight;
 

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Hmmm....not sure, but I think those 2 flat bits are part of the fingers of the pressure plate - and probably the source of your problem.

But I think I can say with some certainty that the round thing is a US penny coin....
 
I would tend to agree, those bits or some like them were likely jammed between other parts and keeping the plate from disengaging.

Time for a new pressure plate. I don't happen to have one or I would happily offer it up.
 
jvandyke said:
While inspecting my pressure plate these fell out, no idea what they are, I will investigate inside the PP more later tonight;
Click to expand...

Not good, prolly part of the riveting for the fingers I would imagine. If you want, I have a good used (very low mileage) PP you can have for cost of shipping. I removed it when I was figuring out my clutch problem (whcih was in fact the fork lever)

667AC455-339D-48A8-9144-675DB367814B_zpsecr3cenj.jpg
 
I think I kept the PP I took out originally, I'll go look for it and also inspect the PP with a scope in it's guts
 
I can't find anything wrong with this thing, some shiny spots around the edge (shown below), first pic is looking in from backside then two close ups of two shiny spots in there (second one doesn't' look so shiny in the picture it it's another clean spot), maybe these two bits were wedged in there and fell out with totally relaxed PP after removal, they fell in? strange there's two and identical, weird
 

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Hmmm...Hey Jeff - perhaps those bits are broken off from the clutch disc ?? And centrifugal force tossed them into the innards of the pressure plate ?? Maybe not - but at least check the disc very carefully. Maybe post some pics of the disc - both sides.
 
Round machining marks suggest they are part of the clutch friction casting. Dissection by drilling out the three drive strap rivets, then removing the friction surface casting from the disc spring will reveal the innards and possibly where these two bits came from. Do inspect the release bearing support, release bearing, release bearing fork and all related parts.

Bernice
 
rx1900 said:
Hmmm...Hey Jeff - perhaps those bits are broken off from the clutch disc ?? And centrifugal force tossed them into the innards of the pressure plate ?? Maybe not - but at least check the disc very carefully. Maybe post some pics of the disc - both sides.
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Yep Bernice is also right.
just finished exam and I think that's it, here's a picture; these "arms" broke off they originally went into the springs? I don't know, but obviously the friction disc is junk. As soon as I looked at the inside of the friction disc I recognized the machining marks.
I don't know how this failed or what effect it would have on clutch operation because I don't understand the design of the friction disc but I hope that was the problem.
Just to recap, suddenly during commute last fall it was hard to get first/second had to start engine in gear to move around. Limped home and checked hydraulics, all appeared okay so pulled it apart. Who thinks this was the problem? I can see how the springs would no longer dampen but would the geometry change enough to not allow disengagement?
 

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Wow. I have seen this before.

My 79 that I had back in high school did this over and over again. different suppliers. all of them saying I was just driving the car to hard.

I never did figure out what was causing it. The car was stolen the last time I removed the trans to replace the clutch.

I would look hard at the dowl pins, maybe bent input shaft, etc, etc.
 
In your pic, is that wear on the pin from the clutch center stopping on it at the end of the spring travel? It looks half worn through from the hook engaging it when the springs bottom out.

Could soft springs have allowed overtravel in the opposite direction to shear off the two ears you found?
 
You actually do not need much to cause your malfunction. I think about it this way... The pressure plate needs everything to happen at the same amount all around. The plate only rises off the clutch plate a tiny bit. If one or both pieces jammed under a fork or two then it would completely alter the geometry for those forks. If it happened on matching forks opposite each other then it might not have shown as unable to disengage. Since it probably jammed on one side and that caused those forks to hyperextend lifting that part higher without adjustment to the opposing fork that side of PP would be lower. This is where the drag occurred. Make sense? Over simplified but just an illustration.
After writing and thinking about it I would say these things got jammed between PP and fork and did not allow the plate to rise when you applied clutch pedal... Seems more likely
Regards
 
Sprung discs just dampen the engagement, so that it's not an on/off switch. Newer cars have a dampened flywheel to further mush the driving experience... it does look like the damper has been hammering the stop pin. But to say whether that's due to the other stop failing or no. The bits wedged in the PP could conceivably effect disengagement, as as the fingers push in, the plate is leveraged outward, releasing the disc. Foreign matter wedged in the base of the fingers could effect lever action. Dunno. I would replace the whole clutch though....
 
I think I kept an old Sach's disc (the one I took out) I'll compare them. Not sure what I'll do yet but thanks all for the input. I was going to put it all back and blame the hydraulics, probably would have been a mistake. Luckily picking up the PP one last time for inspection let the broken bits fall at my feet. FWIW the other side is exactly like this, 180 degrees opposite. Too bad, tons of meat left on those discs, a really cheapskate would undo the rivots and transfer the plates to a good hub......
 
found old disc, it looks okay to me, plenty of meat on it too, little surface rust from sitting around, question is, what failed? and will it happen again?
compare these two, first good, second busted, you can see where the rivet/spacer was getting hammered and the wear into the plate and the "arm" that broke off, Why? hmmm
 

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jvandyke said:
found old disc, it looks okay to me, plenty of meat on it too, little surface rust from sitting around, question is, what failed? and will it happen again?
compare these two, first good, second busted, you can see where the rivet/spacer was getting hammered and the wear into the plate and the "arm" that broke off, Why? hmmm
Click to expand...

Hopefully just a defective disc hub. Maybe the springs are weak & allowed it to slap back & forth. That older one looks great in terms of disc material & no evidence of marking on the stops, so makes sense to use it.
 
clutch reassembled with "old" disc, I think those arms that broke off are there to keep springs aligned and act as stop, both? not sure. The springs have shiny edges like they were spinning around in their enclosures. I don't think loosing the arms would in itself cause a disengagement issue but as noted by rocco and Hussein, the broken bits wedged somewhere could certainly do it, so, we'll see if it operates or not, if all goes well, sometime this weekend, temps here are predicated to flirt with 60 and I have a 4 day weekend so PERFECT timing.
 
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