96Formula6spd

iTrader: (7)

Hey guys so I am trying to figure out why my rear main seal is leaking after maybe 30 miles of driving. I now have 300 on the rebuild and its pretty much marking its territory with cd size oil marks on the driveway. When rebuilding the motor we changed the seal. It went in easy, slid onto the crank nice and has been torqued with a torque wrench to spec. I am kinda pissed off. Any reason it could be leaking? Last engine had a nice dry seal with this same crank. Since we had to change out the wrong pistons for new lt1 pistons we changed it. The dowel pins are there. Maybe just a bad seal? Its not my first time at rear main seal changes and every previous one has worked just fine. Any ideas? All I know is I get to either drop the transmission or just pull everything back out.

shbox

Leaking from the circular seal or the RMS adapter gasket? Or are you sure it's not the pan...

lttransam

iTrader: (12)

i did the same thing.. fresh rebuild and it leaked.. pulled the trans and found that the brand new one i bought had a little nick in it which made it leak. lesson learned just because its brand new doesnt mean its not junk. lol

leadfoot4

iTrader: (1)

Which seal did you install, the neoprene one or the Teflon one? The neoprene gets oiled during installation, while the Teflon one doesn't....

96Formula6spd

iTrader: (7)

Its the circle gasket around the crank. Standard felpro gasket that I have always gotten. Watching it run I could see oil come out of the seal down the housing and then fling onto the flywheel. Directions said dry seal in the box so that is what I did.

cnorton

iTrader: (1)

Did the lip of the seal turn itself inside-out when you slipped it onto the crankshaft? That's not difficult to do, especially with a dry, unlubricated crank surface.

myltwon

iTrader: (1)

Are you sure it's the rear main seal? It could be the intake manifold.

96Formula6spd

iTrader: (7)

It tried the first time but we caught it before it all was on the crank. Second time we held it as we pushed it on.

Yep, Ran the car for 10 mins while running my hand all over the back of the intake manifold and valve covers. Also took video with my phone while the car was running and pictures. Its not the top side. Its all dry now that I fixed the passenger side valve cover. With the car running its 100% the rear main seal.