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7up
May 26, 2011, 07:44 AM
I have a chevy small block 350 engine,I took one of the rod bearing caps off and the bearing stayed on the crank.I took off the bearing and put in the cap and does not fit tight in the cap like it should,does this mean that my crankshaft lobes are out of round do I need to replace it. THANKS

ma0641
May 26, 2011, 01:34 PM
Why did you pull the cap? Was it knocking? Low oil pressure? Was it tight before you pulled it off? Is this a regular or rear main cap?

ma0641
May 26, 2011, 01:38 PM
Sorry, just reread the post and noted rod bearing. Most of the questions are still the same.

hkstroud
May 26, 2011, 05:03 PM
Wait for a real mechanic to come along but chances are that the bearing is designed to fit a certain way. In other words, there are two way to put it in the cap and you chose the wrong one. Take it out and turn it around. If you carefully examine the lower half of the bearing and how it fits with the upper half you will probably see the problem

What you describe would not be caused by a crankshaft lobe being out of round or worn.

CaptainRich
May 26, 2011, 05:56 PM
You can discover a great deal of information about the condition of the crank lobes with a precision micrometer but plasti-gauge.
Generally, if you're not having symptoms like rod knock or loss of oil pressure, you probably won't find any problems. Does the assembly rotate freely without binding while turning by hand?
Like the old saying: If it ain't broke, don't fix it...