clutch parts differences between years

[maytag]

Hey y'all!

Some of y'all may have read my post about shredding a clutch on the drive back form the exhaust shop. less than 5 mikes on it, and the pressure-plate side of the disc completely separated from the rest of the disc. This looked to be a 'new' unit. I don't know the provenance, as it was installed on a parts-car I bought. but it still had stickers on it, and looked unused.
Upon diss-assembly, finding no obvious problems with the installation, I chalked it up to a faulty part.

I re-installed the clutch that was on the car previously. I thought it odd that I could barely get the pivot-nut onto the end of the cable, but since that was the last thing I did in buttoning the car back up, I proceeded.
Sure enough: this clutch spins like crazy, and the friction-point is waaaay at the top of the pedal travel.

So here's where I'm at in my trouble-shooting:
Through this build, I replaced:
transmission. I no longer have the one removed, so I can't compare for differences.
Actuating arm / lever. Again: I no longer have the one I removed for comparison.
Throwout bearing. yup... same deal. threw it away.
and the clutch, described above.

So my questions is this:
were there differences between the years on throwout bearings, actuating arms / levers, pivot points, clutch-packs, etc etc etc? Could I have a mismatch going-on here?

I'm going to pull the trans again tonight, and look it over. But I'd love to hear from y'all on this.
thanks in advance!

[So Cal Mark]

the only differences were on the early cars with the smaller diameter flywheel. Flywheels that have been resurfaced several times can be too thin

[manoa matt]

Ventura Ace had a problem with the throwout bearing, specifically the diameter of the contact face. IIRC he had a bearing with a smaller diameter contact face and it got jambed in the clutch cover springs. There are also metal and plastic throwout bearing housings.

Maytag, did you disturb or change the pivot ball at the opposite end of the throwout bearing arm? Its a bolt with a round head that screws into the front of the transmission bellhousing, and the throwout arm slips over it. If its screwed out too far the throwout arm at the cable end will be angled back and the cable might not hook up. Alternatively the clutch disc can be installed backwards, but I think it would be noticeable when bolting up the cover plate.

[maytag]

Ventura Ace had a problem with the throwout bearing, specifically the diameter of the contact face. IIRC he had a bearing with a smaller diameter contact face and it got jambed in the clutch cover springs. There are also metal and plastic throwout bearing housings.

Maytag, did you disturb or change the pivot ball at the opposite end of the throwout bearing arm? Its a bolt with a round head that screws into the front of the transmission bellhousing, and the throwout arm slips over it. If its screwed out too far the throwout arm at the cable end will be angled back and the cable might not hook up. Alternatively the clutch disc can be installed backwards, but I think it would be noticeable when bolting up the cover plate.

I did not touch the pivot ball. you could be on to something with it, because I have no history with this used trans, other than to install it....
sunnuva..... grumble grumble....

i'm gonna go get dirty and see what I can find.

[manoa matt]

I know the official Fiat factory service manual states specifications/measurements for the adjustment of the throwout arm and the clutch pedal free play, I can't remember if the other manuals Haynes, Chiltons, Clymer, etc are as detailed. If you need those pages send me an email matt.scarton@gmail.com

[maytag]

well... it seems the lever arm pulled off the pivot ball at some point during the last installation.
So we're back in the saddle again.

I've got some adjustments to make to the carbs (new chokes, jets, etc etc), and I need to add a return-spring. Then I'll plumb the vacuum for the advance. at that point, I can dial-in the ignition timing, and tune the carbs.

After that, I need to wire-up the wipers, and figure-out why my tach is bouncing. (I suspect a faulty ground)

Then I'm moving on to the interior! Wahoo! I could be on the road by end of the weekend! all fingers are crossed.