Jim Becker wrote:The TSC seat has a longer threaded end than the other one. I assume the problem here is that it bottoms out before the gasket seals.
That's exactly the problem.
My '53s carb was leaking and it turns out that the needle seat wasn't sealed because the threads are too long. I recognized the seat and needle from a misguided TSC purchase from a few years back.
Luckily I bought a needle and seat from TM a couple years ago for my '67 Cub, but never used it.
The '53 runs GREAT now, but it leaks around the carb inlet...