FWIW - neither my '54 Assembly Manual nor my '54 Shop Manual shows a gasket on either side of the insulator. I have an original Bakelite insulator on my '54 235 w/Rochester B and I don't use any gaskets. No leaks.

I tried using a gasket on each side of the insulator but it raised the carb up enough to make the carb linkage too short. The throttle wouldn't open completely.

My Bakelite insulator has a soft coating on both sides (maybe old gas). It seals it at the carb base and at the manifold. Reproduction plastic insulators probably don't seal as well - even if you lapped the two surfaces of the insulator. Note: Chevs of the 40s advertises a "Bakelite" insulator, but it's really just plastic like all the other reproductions.


- 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.

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