Jerry is absolutely correct IF the pull off piston is the culprit.

However, one issue with the Rochester 2G series (NOT Rochester's fault) is that some "mechanics" have the idea that the air cleaner must be tightened as tight as can be accomplished using a 12 inch adjustable end wrench (31 cm adjustable spanner). This pulls the air cleaner support in the airhorn, which warps the airhorn such that the choke plate will not move. Important to determine if your issue is the warp or the piston.

Jerry's method of wrapping copper tubing around the exhaust manifold will work, and you being in the UK, might be the easiest solution; however, here is another solution:

http://www.thecarburetorshop.com/Heatstovefabrication.htm

EDIT: Ugh - the same filter that consistently converts venturi to venture, converted cm to mm! Thanks, Jerry, now correct units!

Jon.


Last edited by carbking; 07/21/2018 8:58 PM.
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