my 2000 coupe with 165k on original engine may have seen its last day.....after repeated attempts to solve blowing rear main and front engine oil seals....my mechanic says high internal pressures are the cause and the only solution is to replace engine for like 7 grand...any thoughts....they notice oil in the intake manifold even after replacing the pvc lines...thanks nick....vettes rule..i must find a replacement

 

Nick,

You might want to list out what the mechanic has tried, what parts have been changed, and any other symptoms you are experiencing. That will help the gurus here narrow the scope.

Has a cylinder leakdown test been performed? If you pull the dipstick, is there a vacuum or oil/air blowing out when the engine runs?

Todd

 

At 165K on the clock you must have had many thoughts on your game plan to replace the motor. You must love your car to get to 165K, There are many good crate motor vendors, I've had good luck with those on other hot rods I have had. GMPP is a good starting point. If you can't find any vendors buy a Chevy High Performance magazine, they all have adds there. A fresh motor will feel great and can be done for less than 7K.

 

I would pull the oil fill cap off and feel for "blow by" while the engine is running. There should be no real air pressure coming out which would tell you that your pistons and rings are doing their job well. IF you do feel pressure building up under your hand when it's over the oil fill and it is coming out, THEN you know it's time for a rebuild.

There is oil in the intake manifold cause the PCV valve and hoses dump into the front of the intake and there will always be some, regardless of the engines condition. It's so easy to pull the intake off and take a flashlight and shine it down the intake runners in each head on each cylinder, and see if oil is coming from valve stem seals and running down the valve guides and then into the combustion chamber.

Personally, 160,000 miles can be about time for a refresh, but there are much more engines that get well over 200,000 before needing anything. GM did their homework on this engines longevity shooting for 250,000 miles or more. GM even put a LS1 on a dyno and ran it wide open for 50 or 500 hours.....I just read that yesterday in one reference book on GM's research, but forgot how many zeros was behind the figure.

 

Nice LS2 or LS3 crate motor.