Roush 427 leaking oil

[FrankM1]

I recently purchased a Superformance with a Roush 427R, the car did not run for 3 years, the car has roughly 300 miles, and the engine is leaking oil at the back of the engine between the clutch housing and the block.
I suspect and believe that the rear crank seal is defective.

Do I need to contact Roush for that particular seal, or I can find this part at any good Auto Parts store?

Thanks for your help.

[ROUSHAC]

Put some dye in the oil and check to see if you have a leak between the valve cover and head at the firewall area. The oil will follow a path from there down to where you are seeing the oil. Don't ask me how I know. Hope that's all it is, Frank.

[Rwillia4]

How many miles does the engine have on it now? I had a oil leak in my engine for the first ~500 miles. I thought it was the rear seal but I was not willing to drop the tranny to fix it so I delt with the drip every so often. I went for a long 4 hour drive (nothing hard just highway miles) and the leak is gone. I'm not sure if it just needed a long heat soaking run or what. But the leak is gone.

[Tim Brewer]

You can get a seal at any auto parts store. Your engine is just a stroked 351.

[blykins]

Definitely trace it first....and keep your fingers crossed that it's an intake or valve cover gasket leaking.

If it's a 427, I would imagine they used a Dart or other aftermarket block, which uses a one piece rear main seal.

I just assembled a 445ci Windsor with a Dart block and left the rear main seal out until last because they just slide over the crank and fit in a seal bore. Big mistake. I had to drop the oil pan and drop the rear main cap so that the seal would go in squarely and without scuffing it.

If it does turn out to be a rear main seal, let me know and I'll send you one. I have an extra in my garage...and they're anywhere from $20-30 if you buy them from an auto parts store.

[Bill Bess]

I too had a small leak appearing to accomulate at the rear bellhousing and then drip on the floor. I thought it was the rear seal and was expecting the worse. I inspected evreything, valve covers, pan gasket, manifold gasket...everything looked good.
I noticed that the pan gasket ( canton oil pan on FE)) looked a little wet, not dripping..just a bit wet in places, so I tightened it up.
Guess what....no more oil leak, that was 3500 miles ago.

Best of luck, Bill

[Got the Bug]

Definitely give the dye a shot. I think you can get a pretty good dye/light kit at Napa (I bought one from Summit). I had a leak on a Roush 402 and it ended up being the oil galley plugs on the back of the block, which made it look like a rear seal. The valve covers could also be leaking, so check those as well.

[PANAVIA]

Good Point Doug, the pipe plugs (NPT Thread) {not to be confused with freeze plugs} at the back of the block should have been hit with Teflon tape during assembly. If they were hit with a liquid, the liquid may have shrunk in storage. --This brings up a point, we should have a thread on proper care for your motor over long term storage. startup intervals, etc.

[FrankM1]

Thank you ALL for your help, this week-end I will double check all your recommendations. Hope it's minor, if it's not and I have to remove the tranny, how difficult is the job?

Can I remove the transmission like a regular standard car, or do I have to remove the whole engine and tranny together?

[CSCHWER]

If you must remove the tranny, pull the seats and transmission tunnel.