Ok, this is somewhat my first tech article so don't be too hard on me
. I DON'T have pictures on hand but plan to add them soon, if anyone has detailed pictures of my write up please post them. This write up is based on the engine being already disassembled, I assume if you're wanting to check bearing clearances you have a decent amount of automotive knowledge, otherwise do this at YOUR OWN RISK!
1:Checking main bearing clearances begins with mounting the engine block upside down on an engine stand.
2: Install main bearings into bores, being careful to properly seat them. Then wipe the bearings with a CLEAN lint-free rag.
3: Carefully install the crankshaft into the bearings. Try to keep the crank shaft from moving on the bearing surfaces.
4: Wipe the crank journals with a clean rag.
5: Place a peice of the plastigage on the journal. The piece should fit between the radii of the journal.
6: Install the main caps (of your choice) in their proper locations and directions. Wipe the threads of the cap bolts with a clean rag.
7: Install the cap bolts and tighten them according to the tsrm.
8: Remove the main caps and observe the spread of the plastigage. If the gage did not spread, try again with a larger gage.
9: Compare the spread of the gage with the scale given on the plastigage container. Compare the clearance wih the tsrm.
10: Carefully scrape the plasti gage off the journal surface and wipe the journal with a clean lint free rag.
11: If the clearance was within the tsrm specs, remove the crankshaft and apply a good coat of fresh engine oil to the bearings.
12: Reinstalll the crankshaft and apply a coat of oil to the journal surfaces.
13: Reinstall the main caps and tighten them according to tsrm specs.
DIY: Checking Main Bearing Clearance with Plastigage
