QuestionI was told I can repalce rear main seal by removing the crank and forceing
it out with the new one.or does the transmission need to be taken out or
moved I will have a exp. Mechanic to the the job,THANKS
AnswerThey told you ALMOST right, but not quite.
The procedure is to loosen slightly (not remove) the front 4 main bearing caps that hold the crankshaft firmly against the upper bearing surface, then remove the rear main bearing cap. Then the crankshaft will come down a few thousandths of an inch (it is prevented from dropping any further by the timing chain in the front of the engine and the transmission at the rear of the engine.
The rear main bearing cap has the bottom half of the rear main seal in it.
To change the upper half is pretty tricky, but an experienced mechanic will know how to work the old one out of the upper rear main bearing saddle and then install the new upper half in the block. The next step is to install the new lower half in the rear main bearing cap, then re-install that one, and then tighten all 5 caps to the torque spec in the shop manual. This is the least labor intensive way to do it.
Removing the crankshaft is a much more involved procedure; you cannot remove the crankshaft without first removing the transmission, many other parts from the front end of the engine, plus all the rod bearing caps - it is a lot of extra work to do it that way.
Dick
