Main bearing and rod bearing clearances.

[Liltfy]

What's an acceptable clearance for rod and main bearings? I'm not racing and not a perfectionist, just need to know if I'm close.

[George Bongert]

Hello Liltfy!

Generally speaking, one to one and a half thousandths (.001 to .0015) of an inch is acceptable for both main and rod bearing clearances. You might be able to go to two thousandths (.002) of an inch clearance, I personally don't recommend .002 because the greater the clearance, the more risk you run of "pounding out" bearings, especially when the engine is cold (waiting for the oil pump to get oil to the bearings,) high RPM's (or "revving" the engine when it's cold,) or when the engine is hot and the oil has lost some of its viscosity thus allowing the oil to be thrown off from bearings more quickly. Hope this answers your question.