How hard of a job is it to replace the rear main seal with the motor in the car?
I know it's leaking cuz it's marked a nice spot in my garage on the carboard i have sitting underneath the car.

 

Year model, engine?
Positive is the rear main seal?

 

72 Olds 350 ,yeah pretty sure ,the colour of the fluid is like motor oil plus I can see the drips on the trannie inspection cover

 

It's tough. Take out the motor mount bolts and raise the engine a couple more inches. Everything is pretty tight in there though.

 

Maybe just be stating the obvious, but clean everything real well to make sure it really is the RMS and not something easy like valve covers or intake manifold just running down the backside. How bad is it - a few drops, a puddle, or add a quart every time you drive? Sometimes an old car just has to mark its territory.

 

If it really is the RMS it can be done, its just time consuming in the car. As 455man said unbolt the engine mounts, raise the engine up at the front, & drop the oil pan. You might have to pull the distributor out to allow for the engine to go up high enough in which case make sure it is in the #1 TDC position. The oil pump will have to be removed & then drop the rear main bearing cap to get at the rope seal. I haven't done one still in the car for a dog's age, but you used be able to get the rope seal with a plastic tab that helped with pushing the new seal up around the crankshaft.

 

It can be done, aint easy, decision of how bad is the leak.
My vehicles don't leak oil.
They ooze character.

 

I guess i'll leave it for now ,it's not streaming oil out all over the place and i'm not losing a lot of oil so it can wait till the engine gets pulled.What's that saying ..Let sleeping dogs lie??

 

It's "marking it's spot".

 

just like a vintage Harley !