I have an 82 351w that is sitting on a stand.

The chilton manual says to loosen the bolts to let the crank shaft lower a little bit when changing the Rear main seal (along with taking the cap off the last one).

My question is, since its on the stand, I was planning on just flipping the block over and changing it out. Will I still need to loosen the other bearing bolts? Will the weight of the crankshaft make it more difficult?

I guess I can always just keep the block upright and change it from the bottom, and I will if that is the best option.

Just wanted to get your thoughts.

 

Loosening the crank bolts will take some pressure off the seal allowing you to rotate the old seal out and the new seal in more easily. Flipping the motor over will not accomplish this because the weight of the rotating assembly will still be on the upper seal half.

Hope this helps.

 

That's what I was afraid of. Just hoped I could get it done with the block flipped over.

 

I do them on an engine stand quite often. Loosen the other main caps as book says. It helps if you have a friend to help, use a prybar and push up on crankshaft. Of course make sure you are prying somewhere that will not hurt crank. I have a friend do the prying while I take seal out and put new seal back in. Works great for me, I have done many this way, of course I just showed my age by saying many. I was around back before one piece rear mains were even known about.


Just to make sure you do know about off setting the new seal??

 

I was able to change it last night with no issues. I loosened the bolts as the manual stated and just got under the stand and did it.

I did remember to do the offset.

 

Cool....glad you got it done. Of course under the stand a lot easier than under the truck....