The Stovebolt Site Forums The Shop Area Engine Shop Can I get a Carb that Doesn't Leak for my 235?

The rochester B leaks, and I'm looking for a Carter YF, but I hear that will leak, too.

Are there any other choices that might work on my 235, that won't leak?

Any carb will leak if the gaskets are no good and/or if they are worn out. Where is it leaking from? If you can, rebuild it. If you can't, you can probably get a Holly from your local parts store but it will leak in a few years too if it just sits and dries out.

Well, I have already rebuilt it with parts from the local store.

It leaks from the lower butterfly when shut off. the guy at the carb shop says thay all do it, even if i switch to a Carter YF,
because the gas percolates above the hot manifold.

Switch to Carter? or what about a Holley for my 235? this seems too simple. we should be able to get a carb that doesn't leak and overflow when the engine is hot.

It (the rochester) floods, and leaks , and is almost impossible to re-start when flooded and hot.

I rebuilt it all to spec with new parts and gaskets. and it's still a mess. what to do?

Holley? Part number?

find a w-1 or a good yf carter, and no they all do'nt do that! ROCHEST ME OFF'S DO !!! are you sure you have the right carb spacer gasket,and mounting height.

I normally have to adjust the float height until it doesn't leak. Usually it takes just a small change. It leaks out of the throttle because it is flooding inside.

Unfortunately, leakage around the throttle shaft after the engine is turned off is quite common (maybe the norm?) with modern fuel.

When the engine is turned off, the fuel pump inlet check valve closes, preventing fuel from returning to the tank.

The heat from the engine now causes the fuel in the fuel line from the fuel pump to the carb to expand, thus pressurizing the fuel line to a pressure which the carburetor float cannot withstand.

Fuel from the fuel line dumps past the carburetor fuel valve into the float bowl, raising the fuel level above the main discharge nozzle.

Fuel drips out of the main discharge nozzle down onto the thottle plate. If the throttle plate is closed, it runs out the throttle shaft. If the throttle plate is cracked open, some runs out the the throttle shaft, and some runs down into the engine.

The cheapest (non-political) solution (other than non using the vehicle):

Buy the lowest octane, name-brand fuel that does not "ping" in your vehicle. This will minimize but not solve the issue.

The best solution:

Install a three way filter right at the carburetor, and run a "return line" from the "vapor tap" on the filter back to dump in the top of the fuel tank.

Jon.

I believe it would be a 1904 Holly. Parts store should be able to verify that.

Is there a specific list of Carter YF part numbers that will confirm for me which one I should use for my 235?

I have seen pictures of YF's that have automatic chokes, are they all that way? Can I use one like that?

Or will any YF fit and work OK?

I'm thinking about just rebuilding the B again.

The Carter YF that would work is the 2100S. Use caution etting them, though, as there is a ford version that is jetted WAY to rich for Chevy use. Sometimes the rebuilders don't get the right carb in the right box.
As far a Holley goes, yes, the 1904 will fit, but most of them seem to be made for a right side intake (ford, IH, GMC V6) so some modification might be necessary to make them fit a Chevy. If you get lucky, there was a lesft side version used on late '50s GMCs that would work. Rejetting is easy, as they use the same jets as the later 2 and 4 barrel Holley carbs.

I had that problem too but found that most of the fuel ran accross the butter fly valve and out the side of the carb. But the unit was quite old and the hole for that butterfly shaft was worn. I took the butterfly out and shaft out, cleaned up the hole and used some JB weld to put on the body where the shaft goes through. Put some oil on the shaft as a releasing compound and reassembled. When fairly hard i worked the butterfly. Also polished the shaft and hole some, later on. It has good close tolerance now and the fuel. stays inside the engine anyway.