3.8 intake manifold

abe · 06-19-2005, 08:15 AM

anybody out there ever take your intake manifold off of your 3.8L engine, and find that the wrong intake manifold gaskets were used at the factory? What I found on my '91 park avenue, with 155K miles, is that there is a 1" or so diameter hole, right by the #2 and #5 exhaust valves on both heads, where the original manifold gasket bypassed these holes. Dirt and crud had formed in there over the years. Stunned? You bet!! That assembler should have been fired on the spot that day.
abe

**BillK** · 06-19-2005, 12:55 PM

Abe,
Ever think that the gasket used originally might not have been wrong at the time ? Maybe they redesigned it later ? Where do the holes go to ? Inside the engine ? Did they do any harm ? The engine ran 155K miles without a problem from them didn't it ?
Just curious,

abe · 06-19-2005, 05:13 PM

Bill
The replacement gaskets that I picked up are correct. They don't bypass this hole, and yes, if you look right inside this hole in the head, you can see the pushrod for the rocker arm for the exhaust valve. This hole was full of crud. On the intake manifold, I haven't yet taken the time to see where this port goes. If it was on the intake valve, I can see where some damage may have been caused, but it's on the exhaust, so the damage if any is minimal. Plus, the 155K miles are pretty much highway, so it's not like it's been driven down dusty dirt roads every day. But I'm curious to see why you seem to think that these gaskets were correct at the time of assembly. I work in an assembly plant, and if something is not right, we stop the line immediately and get it fixed. It's called protecting the customer.
abe

**BillK** · 06-20-2005, 05:04 PM

Abe,
I guess I have to see a picture to understand what you have. Is the hole open to the outside of the engine ?

abe · 06-20-2005, 07:55 PM

Yes, it is. the original intake manifold gasket bypassed this hole on both heads, and when the intake was mounted to the top of the engine, the port on the intake and the port on the head were exposed to the elements. My new gaskets that I got from Azone (Felpro) are the correct gaskets, and do not bypass this hole. If it helps, my heads casting # is 4250. I have to assume that thru the years it created its own gasket by filling up with crud. I never did see any blowby coming from the engine anyplace. Really, this engine ran super. The heads are off of it now because I'm grinding the valves.
abe