1937 ul intake manifold

[ldfly112]

I am having trouble with the intake manifold not pulling up to the correct location and the manifold nuts are tight. I am using peek seals not the brass original seals any ideas what i am doing wrong

[Steve Slocombe]

Harley said leave the cylinder base stud nuts loose when fitting the manifold and that remains a good tip. Those fine threads need to be spot on to get started. The parts book says 1937 is the last year using the VL inlet manifold before the new style 1938 intake came out, and I've never worked out why. Did the UL cylinders with -38 casting numbers have the inlet nipples in a slightly different place?

[T. Cotten]

Please be aware that the manifold spigots do not touch the inlet nipples, and the seals cover the gaps, Idfly,

So the manifold will not appear to align if held flush to the nipples.

Please bubble-test while installing, to find the 'sweet spot' where it seals.

If your using mass-produced PEEK seals, they usually cross my benches as failures when they are not a squeeze-on fit upon the spigots, or if they do not match the bevel within aftermarket nuts. And since they were made to thin brass specs, they tend to arch in the middle.

....Cotten
PS: Loosening the cylinders risks gasket failure, and there really isn't that much play anyway!