Intake leak observation

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DanM
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Intake leak observation

#1

Post by DanM »

When I put my engine back together I made up a plate with air hose connection and bolted it on the manifold in place of the carb.
With any air pressure- 5-15psi, the soapy water bubbled around the intake clamps. I use stock clamps.
No amount of futzing with the clamps or rings would help.
I removed the new o-rings and found they were made by butt welding the ends of a rod together. These butt welds make raised rings at the joint. I figure the raised area can't seal in the groove.
I replaced the o-rings with a pair from a NOS (1985) HD gasket set. These look molded in one piece, with no joints visible, no parting lines.
These sealed right away without making the manifold clamps overly tight at all.
I tried a piece of silicone tape, and it didn't solve it altogether- but the type of O-ring did.

Dan
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Re: Intake leak observation

#2

Post by Cotten »

The only question is: Why did it take Harleydom so long to discover soap?
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