What would be the most probable causes for a 455 rear main seal to start leaking badly after only 6,200 miles on a complete engine rebuild?
Also like hugger wrote "Excessive crank case psi?", that can be caused by the PCV system not functioning properly. That system basically sucks out the excess pressure built up in the crankcase, without it most of the gaskets will fail in a short time and your engine will be marking its territory all over the place! GL Derek
1. Failure to install the seal properly 2. Excess crankcase pressure 3. Failure to install the seal properly 4. Seal groove not appropriately concentric to the bearing housing (Lip-type seals, not rope-type. Rope seals are fairly forgiving of concentricity problems.) 5. Failure to install the seal properly 6. Defective seal. 7. Too much sealer on the rear main cap--prevents rear cap from seating properly 8. Failure to install the seal properly 9. Misdiagnosis--oil is not leaking from rear main seal. Rear main seal blamed for a leak somewhere else. 10. Failure to install the seal properly. 11. Incorrect seal installed. 12. Excess bearing clearance, crankshaft is flopping around in the bearings 13. Crankshaft surface where seal rides is damaged
I didn't mention installed incorrectly cause it lasted 6700 miles before it started pissing if in fact it is what's pissing. Usually when they are installed wrong they start leaking immediately
I spoke to the guy who built the engine and he said the seal was a Fel-Pro rubber. He builds performance engines including Buicks and he said he never heard from customers about a seal failing this fast.
Excessive Blow by cause crankcase psi take oil cap off while engine is running if it smokes or sounds like air rushing out you need better ventilation
I had a seal fail after a 25 min break in. I got all kinds of advice like crank wasn't concentric, cracked cap and turned wrong way. I took it apart and it was just a bad seal. It must of been old. I threw on a TA seal and a year later, still no leaks.
Man Dennis bummer to hear that I just did my impala pan and same thing happened I think I pinched the gasket though I need to get it up in the air and fix it...give me a buzz if ya need anything
I've got a PCV valve and there hasn't been any sign of blowby. The mechanic that works on it got the pan off yesterday and said the seal was out of place. We ordered a new neoprene seal from TA. Looks like the engine builder used the wrong seal or didn't install it properly. Disappointing, considering the $$$$ I paid.
Thanks, Joseph. Looks like everything's under control at the moment. Missing some good weather out here for top down, though.
