Visually detecting a rear main seal leak?How?

[pauls340]

For those of us who have never had a rear main seal leak, can someone describe how you can visually and mechanically see it. I have oil leaking / dripping from oil pan drain bolt, inspection cover hole, mini starter and on the trans. Thanks for the help. This is on a stock 340, '71 with a A833

 

[rumblefish360]

Well, it's ethier the rear main or a oil plug that will leak from the rear of the block.

With the car up on ramps, slide under and see if you can see the crank spinning.

It could be a minor valve cover or intake leak since it is on the starter.

 

[greenhornet]

Fix the oil pan drain bolt leak first then go from there... It might just be blowing back on all the other parts you mentioned if its leaking bad enough...

 

[pauls340]

I know the oil pan bolt is not leaking at all. Looks like oil is coming from the backside of the oil pan up by the scattershield.

 

[cudamark]

I'm presuming this is engine oil.....If you have a full dust cover on the transmission, pull it off and see if the front side of the flywheel is oily. If it is, it's probably the main seal or gallery plug leak. If the flywheel is dry, It's something else.....oil pan gasket, intake gasket, oil pressure sender, valve cover gaskets, etc. You may have to clean off all the old oil to see where the leak is coming from.