The Ford Barn - View Single Post - New motor break-in with babbit bearings

PC/SR · 01-07-2018, 09:59 PM

Babbit bearings make no difference in break in. I just gradually accelerate to about 45-50, then let off down to 25 or so and do it again 4-5 times. The deceleration sucks oil up the rings. The accelleration forces the rings against the cylinder walls. Do it a few times over a couple days and all is well. Just for fun, try tracking compression tests. Check compression initially and as you proceed. The compression will increase over a 1000 mile period, but that does not mean you cannot drive it normally after a few accellerations. It just takes time for a perfect fit, but a perfect fit is not necessary for a driver.

01-07-2018, 09:59 PM	#10
PC/SR Senior Member Join Date: May 2010 Location: Santa Rosa, CA Posts: 1,279	Re: New motor break-in with babbit bearings Babbit bearings make no difference in break in. I just gradually accelerate to about 45-50, then let off down to 25 or so and do it again 4-5 times. The deceleration sucks oil up the rings. The accelleration forces the rings against the cylinder walls. Do it a few times over a couple days and all is well. Just for fun, try tracking compression tests. Check compression initially and as you proceed. The compression will increase over a 1000 mile period, but that does not mean you cannot drive it normally after a few accellerations. It just takes time for a perfect fit, but a perfect fit is not necessary for a driver.