No Leak Intake Flanges

[Frankenpacer]

Probably applicable only to the EXP Shortwings or those who can pursue a 337, this product is so slick I thought I'd share.

After trying several different gaskets including paper, composition, silicone and even dead soft copper, I threw a rough O ring idea at Ross (SDS) and sure enough, he took it and improved it. Some prototype parts showed up in my mailbox and I promptly installed them on the RV -8. Keep in mind the -8 is an angle valve, requiring the added step of cutting and re welding the tubes to replace the flange clamps. Easy, but not required on the parallel valve engines.

Anyway, once the new clamps are on the tube, you simply install the O ring over the inner retainer and slip the assembly in place between the head and clamp. Snug up the bolts to spec and you are done. Unlike with the paper gaskets, it is impossible to bow the retainer or over compress the O ring. It's simply a install and forget thing.

There have been many attempts to "fix" the induction leaks at the head over the decades since the Lycoming was designed - this is finally the one that works.



See full thread here: http://www.vansairforce.com/communit...d.php?t=161030

[Subsonic]

Give it time. They all leak eventually.

[Frankenpacer]

Spoken like someone who has battled the crumbling paper gaskets and bowed retainers like I have. Time will tell, but I wouldnt be surprised if these make it to TBO.

...and if they don't, who cares? Its a $.50 cent O ring that can be changed in about 2 minutes.

[andya]

Had a friend who used AN 900 (copper & aspestus (spelling) for the intake gaskets, nothing
special about using other parts, seem to work fine for the 7-8 years he flew his Cherokee 180

[Frankenpacer]

Thought about trying the AN900's, but on the stock Lycoming setup the tube still sets proud of the retainer so the gasket wont be "retained" except by crush, and THAT is still set by the amount of torque on the bolts. With this setup the crush depth of the silicone O ring is machined into the new retainer. No finesse required. Smoke it down and walk away.

[Steve Pierce]

Some Lycomings use o'rings on the intake tubes already don't they. Somewhere I remember seeing that. I just replaced #1 intake gasket on this O-360. Lot of blue dye in the tube.
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[Frankenpacer]

The 200 HP angle valve engines use O rings to seal the tube to sump plenum connection, but the tube to head is still the flat composition gasket.

[Jeff J]

Some Lycomings use o'rings on the intake tubes already don't they. Somewhere I remember seeing that. I just replaced #1 intake gasket on this O-360. Lot of blue dye in the tube.

Primer leak?

[Steve Pierce]

Primer leak?

Didn't leak while I had the intske tube off. Someone put the primers in the top of the cylinders where the injectors would be on a fuel injected engine.

[Jeff J]

Interesting... Might be dripping until the line is empty. Vacuum in the intake could keep it from draining (no air available to replace the fuel in the tube) while the engine is running... maybe.