Main Bearings in H

BB

Replace only one bearing at a time so the crankshaft isn't damaged. To remove the bearing shell that is above the crank journal in the block, use a cotter pin with the two sides bent into the shape of an italic "T" - when you place it in the crankshaft oil hole, you will understand. Make sure the bends are sharp enough to only contact the bearing shell. Place the loop of the cotter pin in the crankshaft oil hole (a dab of grease will help it stay put) and rotate the crankshaft carefully in the direction that will roll the shell out away from the locator notch. Oil up the new shell and replace it in the block in the reverse order. Torque the cap bolts to 75 ft.-lbs. and check for binding. There should not be any. If OK, proceed to the next bearing. If you think it would be easier for you, it is OK to drop the oil pump (2 screws) as it doesn't affect ignition timing like some car engines. The final step is to verify the bolt torque and wire them up.

The mains can be done without splitting the tractor, but unless you need it for plowing next week, why not take it apart and fix everything that needs fixing ? I think mains were about $60 from the local IH dealer.