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greenchevy
05-15-2009, 05:12 PM
how do you change the main bearings on the crank shaft with the engine in the jeep? also should i use a light weight or heavy weight oil to put on the mains?

kryptonitexj
05-19-2009, 11:12 AM
Drop oil pan, Start at the first main bearing remove the (2) bolts then the main Cap half of the bearing will be on that journal, then with a small flat head push the other half of the bearing out thats on the top half of the crank(note where the oil hole is and replace accordingly). Apply a little assemble lube on the new bearing and slide one half on top of the crank push it home. for the lower bearing place it into the journal cap with assembly lube and torque to 85 ft/lb (IIRC) Do the same for the rest. on the rear most bearing i would recommend replacing the Rear main seal for good measure(While you are in there). I would also recommend replacing the oil pump depending how many miles are on it. just FYI the stock oil pump housing is aluminum so when it gets hot the aluminum expands causing the gears inside the oil pump to have greater clearances between the pump housing and gears effectly causing less pressure to be created. (I replaced mine with a Hi/lo cast iron Hi volume unit.)

Good luck. Its not hard just a little time consuming lying on your back. Just pay attention to what your doing and replace everything the way It came out.:thumbsup:

DETOURS
05-20-2009, 07:19 PM
Drop oil pan, Start at the first main bearing remove the (2) bolts then the main Cap half of the bearing will be on that journal, then with a small flat head push the other half of the bearing out thats on the top half of the crank(note where the oil hole is and replace accordingly). Apply a little assemble lube on the new bearing and slide one half on top of the crank push it home. for the lower bearing place it into the journal cap with assembly lube and torque to 85 ft/lb (IIRC) Do the same for the rest. on the rear most bearing i would recommend replacing the Rear main seal for good measure(While you are in there). I would also recommend replacing the oil pump depending how many miles are on it. just FYI the stock oil pump housing is aluminum so when it gets hot the aluminum expands causing the gears inside the oil pump to have greater clearances between the pump housing and gears effectly causing less pressure to be created. (I replaced mine with a Hi/lo cast iron Hi volume unit.)

Good luck. Its not hard just a little time consuming lying on your back. Just pay attention to what your doing and replace everything the way It came out.:thumbsup:


What he said...........you may want to jack up the front of the motor, it helps. (disconnect motor mounts)