72' Blazer Rear Main Seal Replacement

[RunTMCfan]

In order to stop my oil leak I'm gonna install new seals on the oil pan. My buddy says the older 350 has a two piece rear seal and I should replace that as well. My Haynes manual has terrible photos on how to do the job.

Can you guys point me to a resource with good photos and instructions?

[RunTMCfan]

Anyone...

[bouncytruck]

Have you picked up the new gasket from the parts store? I believe you can get single piece gaskets. I've never changed an oil pan gasket while the engine was in the car.

It is just a chevy 350, right? You should be able to look in basically any chevy 350 manual to see what needs to be done. I think most of it will be clear once you actually start the process. You may need a hoist to lift the engine up a bit for clearance. You'll probably want to pull the pan to clean it up and there might not be enough space without lifting the engine up a couple inches.

I put Fel-Pro gaskets on my valve covers. They worked great. Much better than cork.

[RunTMCfan]

I planned on pulling the pan. Someone said I needed to pull the trans and tcase. I think he was thinking of the one piece. I will probably just have to start working on it. It usually makes sense then. I think I have a rebuild book somewhere that might have better photos.

[bouncytruck]

I don't see why you would need to pull the transmission and t-case. There should be enough clearance around the bellhousing to access the oil pan. Have you climbed under the rig to see how much clearance you have?

[RunTMCfan]

With a two piece you can access it fine. I havn't looked yet the but the manual mentions nothing of removing the tcase and tranny. That would have bummed me out being that I just put them back in after rebuilds.

[FRENCHBLUE72]

Make sure you get the one pc oil pan gasket worth every cent imo... Are you sure its a rear main and not the oil pan gasket???

[RunTMCfan]

We did an iodine test. The light showed leakage from there, the oil pan and from the valve covers. I just put on new valve covers and gaskets about two months ago. I used some crappy covers and they flex a little. They don't seel very well when they flex. Probably gonna get some edelbrock covers. 10 years ago I could get plastic Hartman covers and they worked great. My buddy swears by them but I can't find them anymore.

[EFI70Blazer]

When you get your rear main seal, it has instructions how to install it. Basically once you get the pan off, you will need to unbolt the oil pump from the rear main cap and also remove the bolts to the main cap itself. I usually use two of the bolts from the main cap once you get them out and use them to rock the cap back and fourth until it lets loose. By the way when you remove the oil pump, the rod that goes to the disributor will be attached to it. Now would be a good time to replace the plastic sleeve that holds the two together. Basically just break the old one off and install the new. Now that you have your main cap off, the piece that is still up in the block needs to be removed. Use something that WILL NOT DAMAGE the crank to push the seal out enough so you can grab it and pull it the rest of the way out. When installing follow the directions for the seal which will come with a small piece of plastic that is used to put the seal back in the block without damaging it. I usually offset the seal in the block so that the lines do not match up with the machined surface, 1/8 inch is usually good enough. Set the other seal in the cap to match the offset, glue the ends with black RTV and reinstall the cap. Hope this helps.

[RunTMCfan]

Thanks.

I will have to see what happens.