I just installed a new traxxas 3.3 on my nitro 4-tec yesterday. I did the break-in just as traxxas recomends and I noticed all through out break-in it had an inconsistant idle. after break-in was complete I pressure tested engine and found the front bearing was leaking, I tryed changing bearings and crank, no matter what I did it still leaked around the front bearing, between crankshaft and bearing.

could I have a worped crankcase?

All nitro engines suck a little air through the front bearing. Look some were else for the inconsistant idle. Like carb air leak or over rich idle mixture.

well I finally got front bearing to seal and now it runs perfect.