Piston to cyl wall clearance ?

While prepping my 466 for reassembly I noticed some consistant light vertical scratches. With L2404F pistons what would be a good side clearance for a marine app ? I cannot find what TRW had recommended, so I am just double checking. I thought it was .003 - .005 and then we add .005 for the marine use. I am just not sure.

Thanks
Jim

.010 sound awful loose for a cold running application.

So .008" is about good then?

Thanks
Jim

dfree383 wrote:.010 sound awful loose for a cold running application.

Actually, this specific "cold running application" is the very reason that performance marine engines are set up loose in the cylinders: The block stays cool and does not expand while the piston sees a lot of heat from the upper rpm and does expand a lot. So you set the bores loose to accomodate the piston expansion relative to the cylinder expansion. (Especially true with #1 & #5 in a jet boat which sees the cold lake water first, set those cylinders more loose than the others.)

That being said, 0.010" is indeed very high for your application, Jim. The L2404 base specification was just 0.002" in the instruction sheet that I last saw, and in your particular application I would think that 0.005" is plenty.

Paul