Is it possible to change main bearings on a 350 chevy in place?
It is possible but extremely hard to do. You can remove the oil pan, loosen all of the main bearing caps, then remove one at a time and replace the bearings. The upper bearing will have to be rolled out from above crankshaft.
I have had dirt go through the engine - stood for approx 3 yrs before firing up. The crank is fine but the bearings are showing damage. This is why I want to do it in place - another is that it is in a '39 chev which means pulling the whole front off the vehicle to get the engine out. What is your advise for rolling the bearings out?
Use a plastic tool to push on edge of bearing to push it out so as not to damage crankshaft. Having all of the mail caps loose will help give a little extra clearance.
I am going to press the accept button because your answers are just what I needed to know. Now I am being a pig and just need to know a couple of things - Obviously the bearings need to be oiled well, however does it help to pump the oil pump with a drill prior to firing up?
When assembling the bearings, coat the surfaces with Lubriplate. It is a white lithium grease that will lubricate the bearings on startup. Yes, it is a good idea to prime the oil pump prior to startup. If you cannot use this method, disable the ignition coil and crank engine with starter until oil pressure builds, then reconnect coil and start engine.
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