72 Clutch and starter

[Bob H.]

HELP! I need some quick accurate advice so I'm turning to you guys. I bought a 72 4 speed and was going to replace the clutch. I ordered a 10.5 clutch as it calls for that. It's a 350. It turns out to have an 11" clutch in it. I am now being told that since it has an 11" in it that switching to the 10.5 means I need a different starter because one is 168 (current) and the 10.5 is 153 teeth. What do I need for a starter? BTW original engine and trans.

[Patrick H.]

Re: 72 Clutch and starter

You need an 11-inch clutch. The books are wrong, the car is right.
Don't swap starters, swap clutch sizes.

[Joe L.]

Re: 72 Clutch and starter

You need an 11-inch clutch. The books are wrong, the car is right.
Don't swap starters, swap clutch sizes.

Patrick and Bob------


Absolutely correct. By the way, if you switched to an 10-1/2" clutch, besides the starter you'd also need a different flywheel and bellhousing. ALL 1972 Corvettes except ZR-1 used a 14" flywheel and 11" clutch. Period.

[David M.]

Re: 72 Clutch and starter

And do yourself a favor while you are in there...MAW...
Of course surface the flywheel, replace the pilot & T.O. bearing, inspect the bell crank and fork(lube), service the trans(inspect gears/syncros, fluid and seals), inspect u-joints and shifter(adjust & lube).

Rebuild the starter.

Replace the positive cable if needed, so much easier with the trans out of the way. Do the neg too, if its questionable while its in the air. 50 year old cables are ready to be replaced. At least unbolt the ground and clean that connection same for the cable under the passenger engine mount,

Lube all 3 pedal pivots.

The LUK clutch is a good reliable set.

Use blue Loctite on the critical fasteners...flywheel, clutch, u joint straps etc,

Pay attention to the disc orientation on the old clutch before removal. Sometimes the new disc isn't directionally marked. It will save you that headache upon reinstallation where you doubt which way is correct.

See how easy I spent your time & money...

[Leif A.]

Re: 72 Clutch and starter

Great tutorial, David.

[Joe L.]

Re: 72 Clutch and starter

And do yourself a favor while you are in there...MAW...
Of course surface the flywheel, replace the pilot & T.O. bearing, inspect the bell crank and fork(lube), service the trans(inspect gears/syncros, fluid and seals), inspect u-joints and shifter(adjust & lube).

Rebuild the starter.

Replace the positive cable if needed, so much easier with the trans out of the way. Do the neg too, if its questionable while its in the air. 50 year old cables are ready to be replaced. At least unbolt the ground and clean that connection same for the cable under the passenger engine mount,

Lube all 3 pedal pivots.

The LUK clutch is a good reliable set.

Use blue Loctite on the critical fasteners...flywheel, clutch, u joint straps etc,

Pay attention to the disc orientation on the old clutch before removal. Sometimes the new disc isn't directionally marked. It will save you that headache upon reinstallation where you doubt which way is correct.

See how easy I spent your time & money...

Dave-----

Yes, all you describe should be done at clutch replacement. However, I do not recommend the use of re-surfaced flywheels. I much more recommend flywheel replacement when the clutch is replaced. With C2-C3 Corvettes getting a proper clutch adjustment can be tricky and even more tricky if a re-surfaced flywheel is used. If one does use a re-surfaced flywheel one should use a spacer between the flywheel and crank flange. The spacer should be of the same thickness as the re-surfacing cut taken on the flywheel. These shims are available in the automotive aftermarket in various thicknesses corresponding to normal flywheel cuts.