A gasket was not specified on either side of the insulator - it was directly against the intake manifold and the carb.

I tried gaskets on both sides of my reproduction plastic insulator, but it raised the carb too high and as a result the throttle rod was too short.

I finally bought an original Bakelite insulator from another Stovebolter. It seals tightly and doesn't require gaskets.

QUESTION:
What is the difference between the early and late insulators that Tim showed? Is it the location of the vent for the power piston? Or do I just have a screwy carb that someone built from various parts?

The vent on my Rochester B carb ('54 235) is close to the mounting holes. The gasket that came with my NAPA carb rebuild kit has cut outs for the vent in the same location as my carb. But the reproduction plastic insulators that I bought - both early and late - have the cut out farther away from the mounting holes. The plastic insulator covers the vent. The Bakelite insulator that I bought from George also had the cut out as on the reproductions. I cut out a new vent on the Bakelite insulator. If I had cut out a new vent at the indented mold mark on the plastic insulator, I bet that the carb would have leaked near the edge - see first pic below.

> Vent locations: Left=Rebuild gasket; Right=Aftermarket insulator
> Power piston vent - similar to my carb

Thanks,

- Lonnie

- Lonnie
My '54 3104
Photos that I have shared on Stovebolt via PhotoBucket are no longer available. Please contact me if you want a photo from an old post.
lonniecook [at] aol [dot] com. I sold my '54 3104 12/12/2017, but I still visit Stovebolt.

OLD STUFF ... houses, furniture, cars, wine ... I love it all