Old carb question

[Dave Harmison]

I can't get my vintage car to run other than pumping the throttle continuously. I think no fuel is getting to the low speed circuit. After much investigation I blew air and poured cleaner fluid over the top of the gasket surface as shown below. I think passage #1 and passage #2 are both supposed to be connected through a cross drilled passage lower in the carb body. If you look closely, you can see that the cleaner fluid is standing in passage #2 so it must be blocked somewhere. The cross drilled passage has plugs in both ends so can't see how to clean it out. Ideas?

[Garey Guzman]

Working on a much less complicated fluid flow device (old caliper), I stopped soaking the parts in the rust/krud cutter fluid after the first few. Then one didn't work. Took it apart and found that corrosion had blocked the crossover hole.

While I've never had a carb sit around long enough for corrosion to build, I wonder if soaking the body in a krud-kutter, corrosion breaking-down fluid would allow compressed air to blow out any residue build up?

Or, you could send it to Butler or you preferred engine builder.

[Purple Frog]

That carb is not disassembled enough.
Pull the jets out of the bottom of the bowls and check them.
Pull out the air correction jets and check them.
The bowl doesn't show corrosion in that picture, but it wouldn't hurt to take it apart and drop it in a gallon of carb cleaner over night.
I blow on the passages with a rubber tipped nozzle.

[David Ferguson]

I'm betting on clogged idle jets. It's pretty common to find a small grit of sand completely blocking the jet. This idle jet is accessed by the brass screws (I think one for each bore, but it's been a while) on the sides near the top, inline with the holes you've identified.