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Discussion Starter #1 (Edited)
I had to replace my flywheel on a 1968 390 HiPo with a toploader. Decided to swap the clutch, pressure plate and throw out bearing while I had the transmission pulled. Everything went back together fine but I'm having a crazy time getting the clutch adjusted.

When I adjust to get the 1/2" freeplay on the pedal, the release lever makes a crazy rattling/banging noise. The noise will not go away until I adjust every bit of the freeplay out of the clutch to the point where I think the clutch is partially engaged.

I used this kit from Summit which should be correct RAM HDX Clutch Kits 88769HDX. Also replaced the anti-rattle spring which appears to still be in place and the pilot bearing. No other changes to the trans or linkage.

Anyone ever see this before? It's driving me crazy because the system is so simple yet I can't figure it out.
 

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Discussion Starter #3
Ha!

I did check the pivot and it looks fine. appears to be seated in the pivot slot of the release lever and doesn't appear damaged in any way from what I can see. Haven't pulled the trans yet but from the inspection plate and release arm opening, everything looks fine and in place.
 

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If you have both the upper and lower springs in place, and the rebound bumper in the pedal support, and a correctly-installed assist spring (with the insulators) under the dash, all you need to do is adjust to have 1/8" of space between the lower pushrod and the release lever. Simply remove the lower spring, and adjust the lower rod for 1/8" of free play. Then replace the spring.
 

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Discussion Starter #5
Thanks. I did try that adjustment. with that adjustment, however, the release lever is rattling like crazy. Like it's getting beat to death by something. that contact does not go away until I tighten the lower rod all the way up until there is no freeplay.

Did not check the springs under the dash as this appears to be something within the bell housing. Also didn't disturb anything under the dash during the swap so doubt it would be anything there as the clutch was working fine before I accomplished the swap. At this point, I'm thinking I have contact between the pressure plate and release lever, although I cant see any impact points.

Annoying at best to pull it all apart again. Especially since it means I'd have to purchase a different clutch. Just out of ideas.
 

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Well, that's just weird. Doesn't make much sense. I wonder if the fingers of the PP are all in the right place and at the right height?
On what should be a quick and easy R&R, everything apparently needs to be scrutinized. On a 390 application. What a PITA.
 

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Im looking for that cure myself. When its not running I can't move the fork one bit to try and replicate the noise
Did your RAM kit come with a Ram TO bearing? I'd check their specific one and see what it can tolerate. I thought I had read a '68, maybe it was '67+ revision, TO bearing can accept a bit of pre-load but haven't found that lately. Mine is in a '66 and drives me nuts so I have been cranking out the adjustment rod little by little. I had the noise gone once but like you it worried me so I started over to try and sneak up on a sweat spot.
NPD lists one TOB as for a Centerforce and an HD upgrade for all THROW OUT BEARING, CLUTCH RELEASE - #7561-10 - National Parts Depot . I should write and ask what makes it better.
 

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^ That's also weird about the TO bearing.
I considered that part when I was thinking about Antoniohickey's situation.
There's only so many TO bearing manufacturers.... you'd think that a design that goes back to the 30's they'd be able to get right.
National and Aetna do most of the "heavy lifting" in that specific design.
 

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Discussion Starter #9
RAM kit did come with a TOB. I eyeballed it when I swapped it out and it looked to be all the same dimensions. Same with the pressure plate but it was two different manufacturers (McLeod vs RAM). Didn't see anything significant with the parts side by side.

The fingers look like they are in the proper position. No idea if they are the proper height but it looks like I can adjust the TOB to have a gap between the fingers and TOB surface. That's when I get the noise though so thinking I'm getting contact between the release lever and pressure plate. The only thing I can think of is maybe the release lever is not correct or just slightly off. Posting some pics to see if anyone can identify anything that looks wrong.
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Thanks. I did try that adjustment. with that adjustment, however, the release lever is rattling like crazy. Like it's getting beat to death by something. that contact does not go away until I tighten the lower rod all the way up until there is no freeplay.
Something is very wrong, this is not an adjustment problem. With the 1/8" gap set, it should be impossible for the release lever to rattle, because it shouldn't be touching anything that moves.

By any chance is the anti-rattle spring holding the lever on the fulcrum inside the bellhousing mis-attached or missing? It is well named, because it's the only thing that keeps the fork end of the lever from moving around, and touching the release bearing to the clutch fingers.

You noise goes away because the release lever is in tension, holding the release bearing against the clutch plate fingers. Bad for the clutch, and it will very quickly destroy the release bearing, which is not intended to spin all the time.
 

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Are you using a diaphram PP ? Those cars were designed to use a 3 finger "long style" PP. Its possible the fork is hitting the PP.

25 years ago I had chatter from a new clutch and new flywheel. I racked my brain. I noticed the disc had scrape marks on it and the flywheel bolts had marks on them. I put a straight edge across the flywheel and the heads of the flywheel bolts were sticking past the surface a hair. I took the flywheel back to the local company and many of those flywheels had the same problem. The recess in the flywheel was not cut deep enough. They pulled a flywheel made from an earlier run and it was correct. I installed it and never had that problem again. My point is you need to check all possibilities.
 

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Discussion Starter #14 (Edited)
Think I got it figured out. Had to pull the transmission to see what was happening. The release lever was hitting the bolts on the pressure plate. Went to take a look at the one that came out of the car (glad I kept it) and looks like a PO ground the bolt heads down to get the clearance needed. Pics attached to show what happened. the three bolts holding the fingers extend beyond the surface of the PP.

I think this may all be due to the clutch lever being slightly off. It's aftermarket so no identifying marks. May be the wrong one completely. Contact was occurring between the back of the pivot slot on the release lever. Just one more Bubba repair job over the last 50+ yrs.

Looking for the correct release lever now to see if there is a difference between what I have and what is correct for the car.

v/r
Tony
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I prefer an 11" diaphragm style for my 67 390. Seems all of the new 12" long style don't clear the original bell house. Factory was an 11.5" long style. But I am no expert.
 

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Think I got it figured out. Had to pull the transmission to see what was happening. The release lever was hitting the bolts on the pressure plate. Went to take a look at the one that came out of the car (glad I kept it) and looks like a PO ground the bolt heads down to get the clearance needed. Pics attached to show what happened. the three bolts holding the fingers extend beyond the surface of the PP.

I think this may all be due to the clutch lever being slightly off. It's aftermarket so no identifying marks. May be the wrong one completely. Contact was occurring between the back of the pivot slot on the release lever. Just one more Bubba repair job over the last 50+ yrs.

Looking for the correct release lever now to see if there is a difference between what I have and what is correct for the car.

v/r
Tony View attachment 763275 View attachment 763276 View attachment 763277
The bolt heads you ground down...... the one's that say "LE" on them are not stock. That's why you had to grind them for clearance.
Those are grade 8's from Lake Erie products.
Those were in a Ram pressure plate? That's crazy. (I see it now in the Summit Racing product photograph)
 

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Discussion Starter #17
The bolt heads you ground down...... the one's that say "LE" on them are not stock. That's why you had to grind them for clearance.
Those are grade 8's from Lake Erie products.
Those were in a Ram pressure plate? That's crazy. (I see it now in the Summit Racing product photograph)
Yeah...the LE bolts came stock on the RAM PP. I haven't ground them down...yet. The picture with the ground down bolts is a McLeod PP that I was replacing. Both PPs had bolts that rise above the surface of the PP which is just enough to cause the issue. Have to verify is the clutch lever is correct but it might be.
 

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so you had a problem with your pp bolts and I had a problem with my flywheel bolts being too high. I wonder what it would have sounded like on a car with both problems
 
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