VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc 28 Carb Leaking

Am I missing something. New rebuild kit on a 28 carb. Checked the float for leaks, no leaks. Set the float according to the manual, 1/2 inch from the lip. Checked to make sure the new jet and housing work. Everything Works fine. Cleaned the standpipe to make sure no blockage, none...Checked the needle for the same none. Bolt it back up turn on the gas and it comes pouring out the hot pipe side like a waterfall. Any ideas?

Check to see if the air hole in the casting is plugged. If so the carburetor will over fill.

Chipper...would that be the little hole on the side of the casting?

Yes it goes from the top of the bowl attaching lip down into the bowl cavity. If it is plugged the float will not rise enough to properly close the needle/seat.

Thanks Chipper...Will try in the morning...

Checked the hole and the hole is open. Any other thoughts?

You have a problem with the needle and seat. I assumed you either replaced them or checked them (or both). All the fuel must go past the needle/seat to get to the fuel bowl. That is unless there is a hole in the carburetor body. Without an extra hole there are only two things that can cause gas overflow: needle not seating, bad seat gasket. If the needle seats properly and the gasket does not leak, fuel can't get into the bowl. There are a few causes for the needle to not seat: incorrect adjustment, wrong parts (don't fit properly), damaged parts (needle not fitting into seat 100%), dirty parts (trash between parts or gum/varnish sticking them apart), float too heavy or leaking or too much fuel pressure. Are you using an electric fuel pump? If so how much pressure on the needle/seat? If more than 1 lb. then that might be your problem. This float/needle/seat will not hold high pressures. They are designed for gravity feed from vacuum tank not a mechanical pump.

Have you tried to rap on the fuel inlet with the handle of a screw driver several times? Don't beat the mess out of it just set up some vibration to break the needle loose. Modern gas quickly forms gums and varnishes that can't be seen. It will stick a needle in a heartbeat.

Have a new jet with seat. Took the needle out and it is clear but will recheck. Using the vacumn tank and was working great all these years then all of a sudden all the overflow began. Will have at it again in the morning...

Bowl fills and pours out the back side of the carb.

Sounds like possibly a defective needle and seat.

Would you believe this? A hellicoil repair was done on the carb and whoever did it drilled through the housing on the fuel inlet thus the needle would not cut off and the gas flowed straight through. Solution...shad tree mechanic. Took a friend of mine who has worked a variety of vehicles over the years and he told me in the old days this was a common problem so to solve it place buckshot in the hole and tap it. Has to be lead to flatten out. Couldn't find any buckshot so he used the tip of a 22 cal bullet, cut the nose and place in the carb to fill the hole, tapped it flat and it stopped the leak. Needle and seat work perfectly.

Ha, never would have thought of using a bullet to fix it but great idea if it worked!

That is thinking outside the box, if it works do it and cheat at all costs.
Tony

As I wrote in a prior post

Yes I would believe it. In the past 10+ years of rebuilding carburetors I have seen many "modifications". Some worked and others didn't.

I believe putting a bullet in a lot of things would fix them.

Man....I totally agree with that!!

That"s why this club is so great!Where else can you get this kind of information.

That's great!

Old timers to the rescue!