New Clutch.....Problems

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I ended up adding a little more free play in the linkage. I now have the factory spec of 5/32" at the end of the fork. I took the car for a drive and I'm still getting the grinding when I put the clutch down near the floor. Something is wrong with the clutch that I installed. The stock clutch linkage seems to be over travelling the travel limit of the fingers. Next step will be to pull the clutch back out. I hope I can send it back for a refund.
I should have expected problems when I saw how they marked the application on the box.

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Too bad you don't have a Clutchmasters shop nearby. (may be you do) I had a new clutch fail. It was probably because I adjusted it by the free play in the petal and not the gap between the t/o bearing and the pp fingers. The bearing failed and burned up the fingers. I bought the clutch off E bay and although it looked good I didn't know whether to trust another. I bought a kit from Brewers and took it to the local Clutchmasters where he put it on the set up jig to make sure it was adjusted correctly. It was perfect and for 10 years it has worked flawlessly.
 
694spd said:
I took the car for a drive and I'm still getting the grinding when I put the clutch down near the floor.....
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If you back the adjustment off until the grind is gone at pedal to floor, does the unit work? Is shifting OK? That .060" gap is a starting point. It's not set in stone. A thicker clutch disc may cause you to run .030". A thicker disc will force the fingers deeper into the pressure plate as well, providing less clearance to disengage.
When it gets to where the clutch does not release and it still grinds the finger backsides you definitely have a problem.
 
If it releases clean and shifts great, then just increase freeplay until you stop grinding the fingers. YES!!! It is that simple!!
 
Daves69 said:
If you back the adjustment off until the grind is gone at pedal to floor, does the unit work? Is shifting OK? That .060" gap is a starting point. It's not set in stone. A thicker clutch disc may cause you to run .030". A thicker disc will force the fingers deeper into the pressure plate as well, providing less clearance to disengage.
When it gets to where the clutch does not release and it still grinds the finger backsides you definitely have a problem.
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There seemed to be very little pedal travel distance between the clutch grinding and the transmission grinding. In other words, if I pushed the pedal too far the clutch ground, I raise the pedal some to stop it, but it did not take much pedal up travel after the grinding stops to where the clutch started grab then causing the shifting problem.
I talked to a friend this morning who thinks that I might have a modified or changed z-bar causing too clutch fork travel . I really don't think so, but I'm going to measure the length of the lower arm to see what it is. At this point, I do not know what the stock length should be?
 
Not saying this is what happened but it may be possible one or more of the fingers have bent/twisted from your initial adjustment (from your findings in post 25) and has lost some adjustment window.
Relating the pressure plate to a three legged stool. If one leg is shorter than the other two, the seat top will not be parallel to a level floor.
If one finger is lower than the other two on the plate it will tend to release later causing out of parallel and you loose adjustment. Another possibility could be a varying disc thickness, a bent disc, or it's just too thick for where the factory has set the finger height.
I'd remove the adjust rod. Visually make sure the release bearing clips are properly engaged (top is hard to see) and the fork is all the way on the pivot.
By hand push the fork rearward lightly and try to determine if the release bearing is contacting all three plate fingers almost simultaneously.
 
If the Z bar ratio has been changed "so much" that there is a tiny difference between transmission grinding, and clutch noise, then you would not have the strength to push the pedal down. From "end to end" clutch release is a simple lever. You make it longer, it's easier to push, goes further at the pedal, less at the clutch

You make it shorter, it's more difficult to push, and less pedal movement results in more clutch movement

SO:

If you are getting clutch noise, either there is something wrong with the manufacture of the clutch.......

or you have a wrong combo of components.........

or the TO by whatever means is simply pushing the fingers too far.

IF IT WILL NOT RELEASE clean by that point, or if the transmission grinds, the there is either..........

something wrong with say, the pressure plate (it happens!!)

or something is "dragging the input shaft, such as a binding pilot bushing

or something is wrong with the trans/ syncro's etc

I would pull it apart and either find a local clutch REBUILDER or else find a press that will accomodate the clutche/ flywheel. l MAKE if you must a "jig" that will allow the press to safely manipulate the clutch in the press. Measure clutch disc release gap and confirm that you have adequate finger to disk clearance.
 
After a lot of careful inspection. Here is what I have found. I dug out the 45 year old pressure plate and disc that was in the car when I bought. I bolted the two to a spare fly wheel. The old organic clutch disc measured .265" compressed. The fingers depressed down .090" from the edge of the pressure plate cover. See arrow in picture.
I got under the car and was able to roughly measure the same gap on the pressure plate also with nothing touching the fingers and I have a huge .375" or 3/8"gap.
The new disc measures 5/16" thick or .3125" when compressed. Thicker because it is new, but I don't believe that the fingers should have deflected 3/8" when the pressure plate is bolted to the flywheel.
So the conclusion that I have is, that I have a pressure plate that has it fingers already traveled something like 3/2 of their stroke before the throw-out bearing has even touched the fingers. So when the clutch releases the fingers just shy of hitting the disc springs.

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The gap on the installed clutch is about 3/8".
See arrow...
Fingers are already too close to the disc springs.

Pressure Plate.jpg
 
Somethings not right with the plate being that close. Maybe not setup for the correct disc thickness. Shims between the plate and flywheel could help but it should work without.
You might also compare the old disc center height to the new.
 
I'm pretty sure that I'm going take the clutch back out and see if I can send it back for a refund. I was think of doing the shim between the cover and flywheel thing, but that is just a band aid for a problem that should not be there.
I need to walk away from this car for a day or two, as for over a month now, I have been running up against a lot of unexpected problems that just seem to keep popping up.
 
I pulled the clutch back out yesterday and now I see where the problem is. It looks like when the pressure plate was assembled the plate was set too low for the disc thickness. This caused the plate to depart too much when assembled to the flywheel and way too low of finger height. I compared it to the clutch that I originally removed. There is about .092" or 3/32" difference.

Pressure Plate 1.jpg


Pressure Plate 2.jpg
 
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The finger height changes with the thickness of the disc. You can't just measure it the way you are and expect to get correct information.

On top of that...it was nothing in the 70's and 80's to raise the finger height .100 so at this point we still don't know what is going on.
 
OP I`m curious, you might get a compass and draw a circle that would just intersect each P-P fork and compare between the two. As mentioned earlier, I believe some P-Ps require a particular TO bearing. I think I remember running into this problem before, where the bearing would enter in between the forks, get hung up and grind. May/maynot be your case. Worth a check.
 
Is this clutch disk made for a Hemi? The new disk has hurcin' springs in the hub. Mabe the disk and PP are mismatched. Perhaps a disk and clutch cover from the same manufacturer would be advisable.
 
rustycowll69 said:
...Mabe the disk and PP are mismatched...
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Could very well be. Post 26 indicates this is a "clutch kit". One would hope they pack the correct stuff.

IMO, I think we agree the plate is not set for the .312" disc that he has since there is virtually no adjustment before driving the fingers into the springs. It likely could be adjusted in but then it can't be returned as it's been tampered with.
MP recommends checking finger height on a .310" standard for stock applications. Finger height should be 1.700".
 
the old PP is painted yellow. Is that a McCleod, or a Weber color? Why not ship it back to manufacturer and get it rebuilt? It worked for 45 years, right? Just freshen it up.
 
rustycowll69 said:
the old PP is painted yellow. Is that a McCleod, or a Weber color? Why not ship it back to manufacturer and get it rebuilt? It worked for 45 years, right? Just freshen it up.
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McLeod was red for as long as I can remember (1979) and I don't remember who was yellow. Back in the day...the DC clutch was green. It's possible that PP was rebuilt by someone who planted it their color.

I agree with RC69. Have the PP you already have rebuilt and use a new disc and be done.
Just remember as the disc wears the finger height moves closer to the throw out bearing. So...the thinner the disc, the higher the finger height.
 
yellow rose said:
McLeod was red for as long as I can remember (1979) and I don't remember who was yellow. Back in the day...the DC clutch was green. It's possible that PP was rebuilt by someone who planted it their color.

I agree with RC69. Have the PP you already have rebuilt and use a new disc and be done.
Just remember as the disc wears the finger height moves closer to the throw out bearing. So...the thinner the disc, the higher the finger height.
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I tried looking up mccleod, and I think they just do diaphragm covers, now. I tried looking up weber, and from what I could gather, all they make are cams, now. I'd suggest finding the nearest reputable rebuilder to rebuild your old one. Someone here on FABO, can probably recommend one near you.
 
rustycowll69 said:
the old PP is painted yellow. Is that a McCleod, or a Weber color? Why not ship it back to manufacturer and get it rebuilt? It worked for 45 years, right? Just freshen it up.
Click to expand...
Weber was always yellow.
 
rustycowll69 said:
I tried looking up mccleod, and I think they just do diaphragm covers, now. I tried looking up weber, and from what I could gather, all they make are cams, now. I'd suggest finding the nearest reputable rebuilder to rebuild your old one. Someone here on FABO, can probably recommend one near you.
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That McLeod web site is a bit of a bugger. They no longer make the BB/Long cover which I still use and Cale Aronson made it adjustable for me. So all you guys with those covers I buy them.

For HP and race use McLeod uses 10, 10.5 and 11 inch Ford Long style plates. That are also adjustable so you can fine tune them. You can also get them with a few more custom touches from Cale Aronson. His company is Black Magic Clutches.

Jack Youngblood also builds them and so does Hyatt.

So there are options out there.
 
Yesterday I shipped the "funky" clutch back to Rock Auto. The kit is no longer stocked so that made it easier to get a refund. I will have to eat the shipping cost, but I'm glad to be rid of it. I do not plan to buy another cheap part store clutches again.
I now need to find another clutch kit and soon. There is a very good clutch shop in the area, but I have been told to not be in any hurry as the turn around will take a month or two. Knowing that, I'm thinking of just buying new now.
I'm still leaning for a B&B as I don't really want to have to remove the pedal over center spring as would be required if I went with a diaphragm clutch.
I'm not looking for a high performance clutch. Just something that is some what close to stock as the vehicle is a bone stock semi survivor car.
There are very few choices when it come to B&B clutches today.
So far I'm seeing a Ram HDX #88766 and a Hays Street/Strip #85-301 as a couple of options out there.
 
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