Steeds

Oil pump base surface grinding

I apologize in advance for overexposure of my Indian innards... I have been told that I need to surface grind the base of the oil pump to remove all traces of wear from where the scavenge gears ride. I then shim the gears with a .002" and/or .004" gasket, just enough to eliminate binding. Just for reference, a sheet of newspaper is about .003" thick!

I am wondering if this means simple removing the light scoring where the right (driven) gear rides in these pics (this will only require removing another .002" or so), or whether I need to also eliminate the grooves at the outer diameter of both gears (which would require maybe .020").

I can't tell if the grooves at the outer diameter are intentional. Expert opinions?

"Now boys, remember, friends don't let friends ride Harleys..."

Engine Update

The Chief bottom end passed Fuzzy's inspection, and he agrees with the plan to hone the cylinders to get perfect clearance and install new .060" over pistons and rings. I will check the valves and guides, but I think they'll be okay. The only other thing is to rebuild the oil pump:

I didn't notice the newspaper caption on the lower right until I was posting this pic. Too funny!

Clearances

Okay, time for some dumb questions... I got a large micrometer today so I could mic the pistons and cylinders. What I found confuses me a little.

The cylinder walls are virtually perfect - glassy smooth, and they measure 3.308" to 3.310". Standard bore on a Chief is 3.250", so that would make the cylinders .060" oversize.

The pistons, however, have some evidence of scoring on the skirts, and they measure 3.298" to 3.300". Since the cylinders are perfect, I suspect that somebody bored the cylinders to .060" over, but re-used the old .050" over pistons... Would someone do that?

Perfect piston skirt clearance is 0.004", but these pistons would have .008" - .010" clearance.

Seems like I should spring for new .060" over pistons, and hone the cylinders just enough to get perfect .004" clearance. Am I missing anything?