Help w/ rear main seal replacement

[68 P.O.S.]

How do you go about replacing the rear main seal? I removed the oil pan & after looking around, I have no clue how to do this . This is new territory for me so help is appreciated.

[68 P.O.S.]

bueller....bueller....bueller

[dave2953]

Is it a one piece?

[jeffspower]

Remove the oil pump & rear main bearing cap. Push on one end of the upper 1/2 seal piece with a flat screwdriver to start slipping it around as far as you can so it is protruding out the other side. Then you can pull it out with a needle nose pliers. Be EXTREMELY careful not to nick the crank's surface with your tools! The new seal will come with a little plastic "shoehorn". Be careful when you open the seal package, it can fall out & you may never find it back. This plastic shoehorn is used in the groove of the seal, so when you rotate it back in, the block's rib it installs on won't gouge into the rubber of the seal. Be sure to oil up both sides to make it slip in easier. You should be able to get it almost all the way in working it CAREFULLY with your fingers. The last little bit you can push home with a flat nosed punch. Make sure you put it in "lip" side towards the INSIDE of the engine. The cap side of course is a no brainer. Notice how the main cap/ block mating surfaces will be a place to seep oil if you bolted it back up without sealer- make sure that little mating area on both side of the cap is clean & oil free, & put a very thin amount of sealer on it, just up to the edge of the rubber seal. Too much sealer can squeeze out getting into the rubber seal lip & create a leak. Put some oil on the lower 1/2 main bearing & draw the cap down evenly, then torque to specs. Same goes for the oil pump.

Hope this helps!

[68 P.O.S.]

I don't know. I'm not even sure how to get to it. I guess I kinda expected it to magically be there and I could change it. I bought the 2 replacement parts and they are both 2 piece double lip. One is offset, one is not. I was going to compare them to the one that's in the engine now and return the one I don't use.

[jeffspower]

Originally Posted by dave2953

Is it a one piece?

Yeah- that would require a totally different approach if you have an '87- up block.

[jeffspower]

The "heavier" lip goes inwards. The offset seal is only needed if a groove/ rough wear is found on the crank.

Quickest way to tell if you have an old 2- pc. seal block is to look at where the flywheel bolts on. If you can see the bolts protruding thru "open" holes, its a 2 piecer'.

[68 P.O.S.]

The block is a '74 so I'm good. So now I hope I can follow your directions w/o screwing it up. Thanks!

[68 P.O.S.]

Originally Posted by jeffspower

The offset seal is only needed if a groove/ rough wear is found on the crank.

Ahhhhh! I was wondering what the difference between the 2 is.