I need advise on getting an intake to seal. It keeps leaking oil past the gasket at the bottom of the intake ports. Here's the long story:
I posted recently about smoke on startup sometimes and when shifting, and that I suspected the intake or valve seals. Well I pulled the intake last weekend and sure enough there was oil all over the gasket at the bottom of the ports. And I could see oil puddled above each intake valve. I changed the gaskets and used some Permatex Hylomar on both sides of each as recommended in a post on the same topic recently "Smokin Merlin 509". (Psalm69, did you get your intake sealed?)
That didn't work, it still smoked. I pulled the intake back off, and sure enough, there was oil on the gaskets at the bottom of the ports, and oil puddled above the intake valves. I cleaned all the oil from above the valves and sqirted oil above the valve seals to confirm none leaked, and no oil leaked past the seals. I checked all surfaces with a straight egde, and all seemed flat. So I suspected maybe the two surfaces were at a slightly different angle. I checked the best I could and they seemed the same.
I then tried a new gasket and used Permatex Form-a-Gasket #1 on both sides of each gasket. Since it was Sunday, and I work out of town during the week, I decided to not start it up until I got home this weekend, to let the sealant set up real well. So today I cranked it up. It smoked real lightly the first time, which I figured was some left over oil from before. But it did smoke some when I reved it. I let it run for a while and shut it off and let it set to see if oil would puddle again and smoke on startup. Sure enough, when I cranked it later it let out a puff of smoke. I'm sure the intake is still leaking. But I don't want take it off again until I have a plan to make sure I get it right next time.
I've check to make sure the gasket matches both parts correctly. The only thing I can figure is the mating surfaces are at different angles, but I don't know why. The heads are aluminum Trick Flow Twisted Wedge heads, and the intake is an aluminum TPIS Mini Ram II, neither of which have been machined at all.
Sorry for the long story. So, what can I try next time to make sure the intake doesn't leak? I was tempted to try silicone around the ports like used on the end rails, but wasn't sure if this was a good idea. Does anyone make a thick gasket for this situation? Any thoughts? Help!
68 SS Convertible
Yellow - (77 Corvette)
383 w/DFI Fuel Injection
on MiniRamII intake,
Trick Flow heads
Tremec 5 sp, 3.31 12bolt Posi
AGR 12:1 power steering
Bent short steering arms
Baer 13" front brakes (Couldn't find time to make bracket for CBB)
550# Hypercoils with Landrum height adjusters
[This message has been edited by 68SSConvt (edited 06-07-2002).]