I am swapping out my clutch on my '73 240Z. Previous owner installed a 5 speed tranny from a 280ZX. I ordered the clutch kit from MSA that had all the goodies - now that the tranny has been dropped out of the car and flywheel resurfaced and put back onto the car, the mechanic showed me the old clutch disc (that had 6 springs) compared to the Excedy (sic?) new clutch disc (4 shorter springs) - more concerning is the pilot bearing tool (the one included with the kit) - it is an extremely tight fit when slid into the hole (tight enough that it makes a loud pop when it finally comes out). The mechanic said the tool should slide in & out pretty easily, and it is gonna be 10x harder to get the tranny back in if the tool is that tight going in and out.

$1,000,000 question is now this: should I have not ordered the 1970-1974 MSA clutch kit for the 240Z and instead ordered a 280ZX clutch kit for my car? The car has the stock 240Z engine installed - I swapped out the differential from the original 180 to the 200 about a year ago.

Edited November 21, 201014 yr by sdaughtry

The clutch disk, pressure plate and throwout bearing collar must match-i.e. taller pressure plates go with shorter throughout bearing collar and vice versa, so you need to know which collar you have. I believe there is a writeup somewhere here about that. You should be able to measure the collar height and MSA can tell you whether it is an early one or not.

As far as the pilot bearing, can you compare the inner diameter of the new pilot with the old one? As long as they are the same, and you l know the tranny came out of it you should be fine. In fact a tighter fit just means less slop when tightening down the disk. That is the only purpose of the alignment tool.

Since you have the old clutch out, why not just compare dimensions to the new parts? Don't forget to look at disc diameter, if you got a 280ZX 2+2 it would have the 240 mm disc.

And the clutch hub spring differences are not a big deal, just different manufacturer's designs. They are there to absorb some shock and vibration when you engage the clutch and when your driving.

As tlorber said, the alignment tool might be tight just to give a more centered alignment. The disc hanging on the tool tends to drop the center of the disc down while the pressure plate is bolted on, making it difficult to get the transmission in afterward. As tlorber implied, the tighter the better on the alignment tool. Measure the diameter of the tool and compare it to the diameter of the end of the trans shaft. The trans shaft will probably be smaller.

The clutch disk, pressure plate and throwout bearing collar must match-i.e. taller pressure plates go with shorter throughout bearing collar and vice versa, so you need to know which collar you have.

Tlorber is dead on.....the 5 speed and 4 speeds are the exact same dimensions. The pressure plates are the only thing that differs, which require the correct throwout bearing collar for proper clutch geometry. My guess is that the previous owner installed the 5 speed up to his 73 240Z clutch which means that he used a 240Z collar for that to work. Measure your collar and if it's from a 240Z you are in business. If not, order the 240Z collar either new or used, press on a new throw out bearing and bolt your transmission up to your new clutch!

Edited November 22, 201014 yr by Diseazd

I think he meant "replace" when he said "swap". He has the correct parts working in his car now and he's been driving it.

A simple side-to-side eyeballing will tell him if there's an issue.

Edit - Actually, a good mechanic would have already compared the new parts with the old to make sure that they will fit. I would be worried that his mechanic is showing concern over the number of springs in the clutch hub and the fact that the clutch tool goes "pop" when he pulls it out. That's either a general lack of experience or preparation for adding charges for a "more difficult than expected" job. Seems odd that the mechanic even mentioned those things...

Edited November 22, 201014 yr by Zed Head

Here is what the fix ended up: the Pilot Bushing was too small in diameter to accept the Pilot Bearing that was provided in MSA's all-in-one clutch kit - the mechanic had to swap it out with a Timken PB22 Pilot Bearing. Everything slid into place like it should have with the Timken in place..

If you look you'll find that Nissan Comp used to sell a pilot bearing as an option to the stock bronze bushing. My understanding is that the bearing is much more prone to failure than the bushing, and I would run a bushing whenever possible. FWIW I once got a clutch kit that had a bushing that had too small an ID on it and you couldn't slide it onto the trans input shaft. Solution was to go back to the auto parts store and get another bushing.