New clutch issue

[Benleroy]

I'll try to run the engine with a crank (without spark plugs) and see exactly what happen when i push down the clutch pedal.

I hope that the lower speed will help to understand what happend when the clutch is released

[dct]

The pressure plate is bolted to the flywheel. The clutch disc "floats" between the two.

Dan

[echelon1]

The pressure plate is bolted to the flywheel. The clutch disc "floats" between the two.

Dan

That's correct, and if the pressure plate is out of balance, or to much tolerance, it will rattle in the clutch bracket notches.
The anti rattle springs will not stop the pressure plate from rattling if the outbalance is too severe.
The rattle is related to engine speed.

Gindi.

[Benleroy]

I've made a detour to the garage after my job.

Here is a new movie
Im pretty sure now that the problem is made by the disc. What do you think'?

http://www.youtube.com/watch?v=lci1Qr_F8Qs

[Marty, SoCal]

When the pressure plate is not clamping the disc is when the noise is occuring, even with the disc stationary, as seen in the video. The noise is engine speed related.

The MOVEABLE iron pressure plate is disengaged, it is rattling against the throwout fingers (which are under spring tension with the fixed cover with the pedal depressed and cannot vibrate like that on their own). The springs from the Service Bulletin hold the levers to the MOVEABLE Iron pressure plate, helping dampen the noise. The new 8.5" replacement clutches do not have the anti-rattle clips. Since none of the suppliers are proud enough of the manufacturer to leave them in their original box, we don't know where they are made (At least in my experience). My gut instinct tells me they are made in Asia, somewhere.

Anyone have a source for the anti-ratle clips from the service bulletin?

[echelon1]

Did you check the clearance between disk springs and flywheel bolts?
You might hit the flywheel bolts with the disk.
That would give you that noise to.
If enough clearance there, the pressure group is the issue.

Marty, below is what I think you are saying:
The fingers are constantly under spring pressure, engaged or disengaged.
The pressure plate is under spring pressure through the fingers when released.
With the clutch pedal depressed, the fingers lift off from the adjusting screws, and the anti rattle springs are pulling the pressure plate away from the disk.
At that moment the pressure plate is floating, and can start to rattle in the clutch bracket notches due to unballance.
Especially if the anti rattle springs are missing or poorly made.

Gindi

[Marty, SoCal]

"The fingers are constantly under spring pressure, engaged or disengaged.
The pressure plate is under spring pressure through the fingers when released.
With the clutch pedal depressed, the fingers lift off from the adjusting screws, and the anti rattle springs are pulling the pressure plate away from the disk.
At that moment the pressure plate is floating, and can start to rattle in the clutch bracket notches due to unballance.
Especially if the anti rattle springs are missing or poorly made.

Gindi"

Exactly

[Gustl]

Especially if the anti rattle springs are missing or poorly made.

Gindi

Very interesting! Could anybody post a pic of these anti rattle springs, maybe compared to the usual springs so we non mechanics (guess I am not the only one) would understand the difference?

[echelon1]

Gustle, These springs are the "clips" that hold under the adjusting bolt and is hooking into the clutch finger.
There are 3 of them, 1 at each finger.

Marty, thanks, glad my English is improving!!

Yours,
Gindi

[Gustl]

Gustle, These springs are the "clips" that hold under the adjusting bolt and is hooking into the clutch finger.
There are 3 of them, 1 at each finger.

Yours,
Gindi

Ok Gindi, I did understand that already before. But I understand there are poorly made springs/clips and there are "anti rattle springs/clips". Just grapping old pics of my 43 MB clutch:

Have I got anti rattle springs/clips here?




sorry, no better pic.

And here we got a new pressure plate, pic of Rons part site.


There is a difference in the springs. The old ones rattle springs, the new ones not?

[bazza46]

I've experienced that exact noise several times over the last forty five years of jeep ownership. I've replaced the clutches many times in my jeeps. Some have rattled like that, some not. The first time it happened it was with an old original clutch that my jeep came with. The rattle started gradually over a couple of years- first just perceptible, then louder .
When I disassembled the pressure plate I noiced that the three holes in the pressed steel frame where the iron plate goes through were worn , with a notch on the thrust side. Likewise, the iron pressure plate lugs hd some wear on the thrust side of the lugs.I welded up the pressing and brazed the iron part and filed and ground the components till there was no clearance between the plate and the frame- just a sliding fit. It worked- the rattle was gone. I also straightened up the hairpin type retractor springs, as they had been bent inward by someone overtightening the locknuts , bending the thin washer over them and pushing them inward.

That lasted a few years till it started again.
This time I bought a proper new pressure plate. This was in 1965, and it was an original part then. The rattle stopped. But by 1974 it had begun again.This was after about 40,000 miles. I welded it up in the same fashion as the first one, but with not so much care. I must have left too much clearance, but it had a small rattle. I left it there till I had to replace the cluster gear and replaced it with a NOS one I'd acquired. No rattle.

So I conclude that the rattle is the iron pressure plate rattling against the pressed steel frame, because of excessive clearance and/or imbalance.
With your case of having a new pressure plate I don't surely know, but must assume that it is a sloppy fit, being new or not. When you get it out, You should disassemble it as per the manual (wear face protection.You don't want to lose an eye if the springs fly out) and check the fit of the iron plate in its frame.

[Marty, SoCal]

The pic on top is the original 7-7/8" Auburn G503 clutch, the bottom one is the replacement 8.5" Atwood type clutch, as used in the M38-A1 and CJ's. (Note, I might have the name brands switched, going from memory)

[Chuck Lutz]

....the one seen in Gusti's pic is like the one on my bench. It has the 8.5" surface and the same clips as seen in the photo and is marked AUBURN (Auburn, Ind.) It has the THREE round sockets between each of the three mountings and on this one....there are also TWO of them which have been drilled out to balance it when rotating.

Auburn 8.5 in..jpg (90.34 KiB) Viewed 165 times

Perhaps yours is out of balance as Ian's explanation seems to cover that as the source of the intermittant rattle....I would point out that Gusti's photo also shows the flywheel has been drilled to balance it as well...

So if anyone assembles the crank and flywheel and it is out of balance....that would probably add to the problem even if the clutch pressure plate itself was balanced....

[Carsten]

Interesting thread....

My old clutch had the same springs:


So, which type of springs are better (if any) - the wire type or the flat spring steel wrap around type?

Frankly, i'm so sick and tired of inferior parts, so it could be very helpful to know the following:

1. Exactly what brand is your clutch setup, Benleroy, and where did you buy it? Pretty sure nobody wants to take the risk, of running into the same problem!
2. What is the best clutch kit available? If that is impossible to find, what is the second best?

I will be purchasing a new clutch and pressure plate very soon, and just want to get the right one THE FIRST TIME!

Does anyone have experience with these parts:




Benleroy, did you mention yours came from Spain? I'm pretty sure the clutch shown above is from a Spanish manufacturer, but not sure of their quality??

[Benleroy]

I'll take a Aspirin and try to understand what you said since my last post

I'll answer all your questions tomorrow after some test.

Carsten this is exactly what i've bought!