|mightymolinekid said: (quoted from post at 05:46:53 01/15/13) I should clarify a little, there are 2 events pictured here. The scored piston and destroyed bearing is from the 1st build. No ether was used for starting, and by the time we got the fuel system primed, the guage was showing 30 psi at cranking. The failure happened on the dyno, after break in, so no I didn't get a chance to cold pull it or lug it. The shop admitted it looked to them like the bore clearance was wrong. The top pictures are after the 2nd build. Cylinder walls look OK, but I have a question for Vic (you devil LOL) what would the explanation be for cutting the valve reliefs in the wrong place on 2 pistons, and not deep enough (but in the right place) on the other 2? And for having the wrong front cam bushing installed, which makes it obvious they didn't measure that clearance upon assembly? I do agree that this is pulling, and we're trying to push this old iron way beyond what it was designed for, so the scored pistons didn't upset me all that much. Hey, stuff happens, but everything else I have wrong here is extremely frustrating.|
That must be one of them quench fanatic shops . It wasnt in wisconsin was it? Allis 226 engine shouldnt have the piston at zero deck it wasnt designed that way . jmho its to tight on ring end gap for the compression and may be piston to bore also . the oil pressure loss is from main bearing clearance or cam bearings in my opinion. you should have put play dough on the piston and tighten valve lash to zero to see the piston to valve clearance by rolling it over by hand before ever starting it . the mashed thickness of playdough also gives a indication of how deep the valve relefs need cut. our shop is always open monday through friday 9 to 5 if you want to bring it down to us This post was edited by MLPANKEY at 06:50:49 01/15/13 3 times.