Mine has a pretty good leak as it sucks your finger if you run it above the runner where it attaches to the head. I picked up a gasket set today to replace it. I re-used the old ones because they were recently installed before the old engine gave up the ghost but maybe it's too compressed or something. Air bypassing the throttle plate will increase the idle big time.
I have a couple Rochester B's laying around if you need a linkage. I copied the Motor book of carbs or whatever from the 50's at the library that covered the B carbs. If I can find someone with a scanner maybe I can upload it here or email it to you.
I've got a Rochester Carburetor manual that covers them all, but the coverage on the B models is only a couple of pages.
My problem isn't really with the linkage. I need to find a kit that has the same accelerator pump piston hookup as the one I have.
Interestingly enough, the casting number is 7025461, IIRC, which would indicate that it was not original for the engine it came off of.
I think I found a good kit at the Carburetor Doctor. They have four different kits for the Bs.
I was just thinking that I used to use a spray bottle filled with water to look for vacuum leaks. If there is a leak somewhere and you squirt it, there should be a noticeable increase in RPM until the water dries up.
