It's rear main seal time, two piece. Can anyone give me a recommendation for a good seal. I plan on doing this with engine in car. Also, any tips to install would be nice, upper removal and install, etc. I've heard that if you install the seal slightly off center, so that the seal ends are not in line with the main ends that it will seal better. Any thoughts?

 

Try to get the felpro ones and ask for the offset ones. They ride in a different position on the crank so if it has a wear mark from the old seal the new one will ride in a different spot.Sounds like You have the right idea and on the right track with Your plans.

 

Your service manual does a pretty good job of detailing the R&R. Also, I'd install the seal ends as the engineers designed; the ends even with the mating surfaces of the main cap and block.

Good luck!

 

I offset the ends and put a small dab of rtv on the mating surfaces. Get everything clean. While number 5 is of I smooth the oil pocket in the 5 main and chamfer the corners in the oil passage.
Take a good look at the lower main bearing while you can. It will give you a boat load of information regarding the condition of your engine,
Depending on the condition of the bearings and the mileage, might change the oil pump while the bottom is opened up.
If you can see the bottom of the pan, run a magnet near the bottom of the pan and see if any shavings stand up. If not, that's a good thing.
Spend plenty of time when buttoning it up. Get in a hurry and you'll have another thread regarding an oil pan leaking.

 

 

Fel Pro #2912 2pc off centred 1/4-3/8" with a little dab of rtv on ends and used a 1 pc Fel Pro oil pan gasket with rtv in the corners and I'm high and dry good luck. Ed

 

Thanks all, The engine only has about 20K but has leaked almost from day one. About a quarter size spot over night. Thought I could live with a little drip but it's driving me crazy not to mention the film on the under carriage. I'm going to tackle this in the next few weeks when I have a whole week-end to dink around. I do have a one Felpro one piece pan gasket on it now.

 

Ive never seen a seal wear groove on the crank journal, just on the harmonic balancer.
Felpro makes a grey rear seal ( cheaper ) and a nitron type ( much better ) that is
brown in color. Offset the seal 3/8 of an inch, use no sealer, and you will
be very happy. Done 3 recently with not a drop of oil to leak afterwards. Just my humble opinion.

 

Just a little bit of a yellow flag. If you are speaking of your 1975, and it has a stock exhaust system, you will have to drop the front Y-pipe. Sometimes that presents difficulties with manifold studs, etc.



The steering gear has to come down as well.

 

Lee, like you, I had one or two drops each time I parked my 68 for the past two years (since rebuild). I choose to do mine this past spring after the thing sat for a few months. (less dripping on your face while changing the seal) There is a real good writeup here complete with pictures so do a search on rear main seal replacement.
In short here is what I did;
Drain the oil, disconnect idler arm at the fframe and move asidee to drop the oil pan on the 68, unbolt and drop the pan, (I didnt need to remove the starter or anything else), remove the oil pump, remove the main cap (may need a gentle tap to losten) I also loosened but did not remove the next cap for easier seal install, remove the seal and clean the area with brake cleaner,oil the seal (not the ends of the seal)and CAREFULLY install both halves of the new seal leaving 1/4 to 3/8 offset , put a small amount of RTV (I used Permatex Ultra Copper High Temp RTV Silicone) on teh mateing surface (look at Paul 74 picture above where it says oil seal compound), put some assembly lube on the cap without getting it on the RTV and reinstall, torque to spec. Reinstall the oil pump.
I used the felpro one piece oil pan gasket with a little blue RTV at the corners. It's much easier to use than the 4 piece gasket when the engine in in the car. I let mine sit overnight to give the RTV a chance to set up. I haven't seen a drop of oil since.
Oh yea, don't try to drive it till you re-connect the idler arm !