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Old 04-10-2008, 10:17 PM
Pete Munroe Pete Munroe is offline
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Join Date: Mar 2003
Location: PVE, CA
Cobra Make, Engine: ERA 289 FIA #2027, 65' 289" PS wheels
Posts: 345
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Default expert? did I shay i was...xpwert? hic

Olddog,

I am trying to remember the entire sequence in my total experience of changing out...two...(not a lot experience!)...sets of gaskets on my 289 iron block aluminum head engine.

The Fel-Pro gaskets, I forget the parts number...are the much despised "Print-O-Seal" I think...they have a blue line of silicone? molded around the intake ports and I think the water ports.

The first time I removed the intake, the gaskets were all distorted as if they had been "squirming"...they had not been retorqued in the first 3000? miles.

RTV had made the seals at the front and rear of the block...that was NOT leaking, only the gaskets where they had broken and dropped into the intake ports.

When I replaced the gaskets the first time I didn't use enough RTV at the rear of the manifold and got a oil leak.

The second time I tried to make the RTV bead taller without adding a huge volume of RTV that would glop into the engine...although I am not sure that within reason it never migrates off into the lifter gallery.

But I did use more RTV the next time I replaced the gaskets...mainly as a "tack" strip to make sure the gasket wasn't moved around the intake ports or to insure? a seal at the water ports. as the manifold was lowered onto the heads.

I ALSO used 4 studs to help drop the intake straight down without displacing the gaskets.

The last r&r I did smear a thin film around the water ports and the center section where the manifold heat risers ports were, again mainly to keep things from shifting during assembly.

As the time interval was only about 30 minutes to get the stuff tacky enough to hold the gaskets in place but not yet setup. It seemed the excess merely squeezed out rather than building up a stable surface as nothing was keeping it from being displaced.

When your engine was assembled was the RTV allowed to SET before the manifold was in torqued down?

I have no doubt some plastics can be tough stuff, or maybe even cured RTV, but from what I saw in my TWO examples, seems like the UNCURED rtv will be displaced...

I now retorque the intake often...

Oh, I have TWO bolts that upon retorqueing do not smoothly take up a tightening, but chatter...they are at the front of the manifold, and always seem to need more torque (22 ft/lbs is the max I go) when none of the other bolts will accept an additional application of torque.

Go figure...!

Pete
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ERA 289 #2027
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