Corvair Forum

I have just finished a transmission swap. Removed a power glide and replaced it with a 4 speed. Got a doner car to make it easier. 1964 model. I can’t get a full release on the clutch disc and finally realized that the main lever assembly is not pivoting properly. There is a ball socket on each end of the lever. The socket on one so is not holding the lever to enable it to rotate properly. The lever is actually rotating at an angle from one side. It appears that the ball socket is not installed properly or is not the right part. Lots of lost rotating motion when pushing the clutch petal which results in the disc not fully releasing. Anyone know what it could be? All settings and adjustments have been made and are correct as far as I can see.

The ball on the trans crossmember is a removable part. It sounds like it might be loose?

I’ll check that when I get back on a lift. Thanks Rex.

It's called a "clutch cross shaft". Was used on most GM vehicles in the '60s and '70s. Anchors in a slot on the crossmember and a bracket with 3 step bolts, a rubber pad, and a metal plate to the body (if you did the swap, you probably already know this). A picture of the cross shaft may help with diagnostics too. Dennis

Dennis I have a picture of the cross shaft but don’t know how to attach it.

Clutch components can get mixed. The early style or later design can be fitted to any Corvair, but mixing components between the two designs will cause problems. Clark's online catalog covers clutch component matching and interchange. This and subsequent pages of the online catalog should help you to confirm that everything matches.


https://ssl.corvair.com/user-cgi/catalo ... w_page=108

The Corvair Assembly Manuals published by GM often contain fastener torque specifications that are not found in the Shop Manuals. The Assembly Manuals for each model year also contain many engineering diagrams and details not found in the shop manuals.






I have attached a section of the 1965 Corvair Assembly Manual as an example. Numbered fasteners in the main illustration diagrams also frequently show torque specifications as a related number surrounded by a triangle, as depicted in the above page example.

I consider the Corvair Assembly Manuals to be an indispensable supplement to the related Corvair shop manual for each model year.

Assembly manuals are available from Clark's Corvair Parts for each Corvair model year. More information can be found in Clark's online catalog on pages 243A - 243B


https://ssl.corvair.com/user-cgi/catalo ... _page=243A

Each Assembly Manual has a nice front and back cover. The manual is 3 hole punched so you can easily put it in a 3 hole binder. They are printed on quality 60 lb. white paper, and the finished product is shrink wrapped in clear plastic. Most of the manuals have about 200-270 pages. I have seen the same type of manual for 1957 Chevy going for $25.00 and up (and rather poorly printed at that).
I CANNOT STRESS ENOUGH HOW VALUABLE THESE MANUALS ARE.

• 1960 CORVAIR CARS (missing 1 section) C7310 2 lbs.
• 1961 CORVAIR CARS C7311 2 lbs.
• 1962 CORVAIR CARS C7312 2 lbs.
• 1963 CORVAIR CARS C7313 2 lbs.
• 1964 CORVAIR CARS C7314 2 lbs.
• 1965 CORVAIR CARS C7315 2 lbs.
• 1966 CORVAIR CARS C7316 2 lbs.
• 1967 CORVAIR CARS C7317 2 lbs.
• 1968 CORVAIR CARS C7318 2 lbs.
• 1969 CORVAIR CARS C7319 2 lbs.

I have a 1964 Monza. I bought a 1964 Monza for a donor car. All parts came from the donor car except for new clutch parts from Clark’s. All parts fit perfectly except that one ball socket on the cross shaft. I don’t know if the owner of the doner car changed anything about the clutch assembly. I have a picture of my cross shaft but can’t figure out how to submit it.

I found that I had overtightened the clutch cross shaft. I removed the engine again and checked all the components related to the clutch system. I don't understand the purpose of the flywheel retainer ring. It attaches the flywheel to the crank. No explanation how to use it. Does the retainer ring go on the crankshaft first, then the flywheel? Does the flywheel go on the crankshaft first, then the retainer ring? Does it matter? I put the flywheel on the crankshaft, then the retainer ring. Everything seems fine except the clutch disc isn't grabbing. Is that retainer ring causing the problem? Do I have a bad pressure plate?

The flyweel goes on first, then the ring.
When I think of a clutch not releasing properly I think of it staying engaged and not disconnecting the engine from the transmission.
In the latest post it sounds like the friction surfaces are not engaging. Is this a new problem?
One thing that comes to mind is the clutch disc and the "flyweel side" position Sometimes they're not marked. I don't remember offhand which gets the side with the longer nose so I don't want to give bad information.

Some other things to consider.
60-63 have a flat flywheel with a flat finger pressure plate. 64-69 have a stepped flywheel and bent finger pressure plate. They have release bearings with a different face. The pivot ball on the differential for the clutch fork are different lengths.

I got it working. I didn’t have the pedal adjusted to produce the necessary pressure at the cross shaft. Clutch fork and throw out bearing wasn’t pushing enough to break the clutch free I guess. I have gears working now. Thanks to everyone for your help.

One more thing I'll mention just for posterity and other folks doing a search.

Sometimes these days a clutch disc with new lining can be a little too thick to release properly.

I have them relined locally at the Clutch Doctor and he said the material is the same as he's always used. I was concrned it was just him but folks have reported the same thing from another (Corvair) vendors.

The thickness of the disc can also be due to the center wavy part, I'm not sure if Belleville is the proper term. I was going through clutch disc cores the other day and saw one in particular that seemed to have no gap in the middle.

I believe in the Tech Guide article .330 is the number someone said is getting towards the upper limit.

What happens is the clutch won't release enough to get the transmission in gear without grinding. It's not usually enough for the vehicle to creep.

The cure is to over-adjust the pull rod for no freeplay of the release bearing and drive the car around slipping the clutch and getting it to wear in, then readjusting some freeplay in there to protect the release bearing. One needs to be mindful of excess heat so the cast iron friction pieces don't get hot spots.

There's a process for adjusting the relationship of the cross shaft to the front cable before adjusting the pull rod but sometimes the possibility of breaking a stuck cable looms large. Getting a EM cable through everything under the dash will help you build character.

The old method where you put the front against something and slip the clutch until you can smell it then shut it off and walk away for an hour is an extreme approach I've used with old slipping clutches. I'd be a fool to recommend it because of the possibility of ruining something but it did work sometimes with a slipping clutch when I was driving Corvair beaters to work 60 miles a day.