getting the pieces together for my drivetrain swap. Mercruiser 120, 2-piece rear main seal T5 from an S-10 with 14 spline 9" clutch kit Cable-operated bellhousing with clutch arm from '78 Monza and the cable Tranny adaptor plate on its way from Vintage Metalworks Resurfaced flywheel from early Chevy ll I sat the clutch down on the flywheel and put the pressjre plate on it, and it sat flat on the flywheel! The flywheel is made with a slight recess where the clutch rides, and though it does seem to be pinned down by the pressure plate, it doesn't seem that bolting it down will add any pressure. I'm trying to figure out my next step. Just offhand I need either a Chevy ll pressure plate or a flat 153t flywheel. Looking online it may be more complicated. I'm hoping I don't have to change everything from the flywheel back...and maybe even go to a new starter for the bigger flywheel! I am hoping somebody here can suggest a compatible part that will bring this puzzle together without selling a kidney!
I think el Scotto has it. If you already have a set of parts that will work, milling/grinding the flywheel shouldn't be very expensive.
The Mercruiser flywheel isn't a flywheel in the sense that it was designed to take a pressure plate and clutch disc. Normally a rubber hubbed coupler bolts to it and the outdrive shaft slips into the coupler.......no clutch disc is used. You might get away with milling it flat like was suggested or finding a regular car flywheel that works. I know the sprint car guys loved these motors and adapted clutches, so there is a way to do it. Don
Just use a regular 153 tooth Chevy flywheel bolts right on . On my 153 Chevy II thats what I used aftermarket 17lb er. 10.4 pressure plate.
Got an original Chevy ll flywheel with the recessed comtact area. They must have had a,flatter pressure plate housing that didn't envelope the plate. At the beginning I searched Mercruiser 120 flywheels and at first sight of ome figured out that they didn't just stay with the automotive one, designed a boat specific one that doesn't accept a clutch assembly. A flat flywheel will probably do the trick, but I haven't found one made for the 9" clutch with the small bolt circle for the little pressure plate. I suppose I will have to get a machine shop to drill one for me. Some other combinations might fail for lack of an available 14 spline clutch disc. Wonder how much the machine shop would charge for the drilling? The idea of milling the raised circumference of the existing flywheel sounds promising, but of course that would also be eliminating some of the pressure plate bolt threads. The flywheel is heavy, like I want it, but I don't think the milled weight would make any difference to me.
No. The trans/clutch/ pressure plate combo was only available with the 2.5/4and the 2.8 V6. There was never the same combo offered for an '85 or earlier 2 piece rear main seal with the sbc pattern.
The pressure plate does NOT have to be the same diameter as the disk as long as the disk is fully covered,ie a 9" disk with a 10/10.4 cover. I used a light flywheel as I wanted quick rev response and car was only 1800.
Seem to have scored a NOS pressure plate for a 4 cylinder Chevy ll, and cheap. That should match with my flywheel and work with my clutch. If it all goes together and works I will keep my eyes open along the way for suitable replacement parts whether they be early Chevy 153 or more likely a more modern fw/pp/clutch combo.
The Jalopy Journal
