The Stovebolt Site Forums The Shop Area Engine Shop Rochester 2 barrel carb spouting gas out the top

I have recently been tuning the carb to try and get my '66 with a 283 to run a little smoother. However, as I was adjusting it one evening I started it up and I had gas spewing out of the top of the carb. Figured it would be a good time to clean/rebuild the carb since the truck was sitting for 10 years. Everything was cleaned, new float, new fuel inlet needle and seat, new plunger, and lots or carb cleaner in every hole. So i put it back in, put a new fuel pump on ( it was leaking), started it up and it run superb for about 5 -10 seconds then coughed and shut off. When I went to start it up again I had fuel coming out the top hole again. The hole actually juts out into the circular air horn (I think that's what it is called). I am asuming the carb is flooding and the hole is some sort of release??

Yeppppppp......
Did you adjust the float???
If so most likely you have a piece of dirt or something between the needle & seat that's causing it, UNLESS you got a bad float w/a hole in it...Joe

I adjusted the float according to the instructions that came with the kit, however my carb # was not listed, so it was a guess at best. I just received the manual for the truck, so I'll go back and adjust it according to that...now that I have a starting point. Thanks for the fast response!!

So I went back and adjusted the float, started it up and it ran wonderful. Ran it up and down the driveway (about .5 mile) no problem. I let it sit for 3 hours, go to start it and the same thing happened!! Gas everywhere! A piece of dirt?? What if I sprayed carb cleaner down that port, then tried starting it?

The tube you are referring to is the bowl vent that keeps the float chamber at the same pressure is the carburetor air inlet- as the air inlet pressure changes with air filter restriction. Spraying carburetor cleaner in that tube will only raise the liquid level in the bowl. The only way fuel can come out that vent if the float level is set correctly is for the needle valve to be leaking and allowing fuel into the bowl. Did you adjust the float drop to the specified distance? It may be that the float is dropping too far and the needle valve is getting cocked in the valve bore and not shutting off properly. You adjust the drop by bending the vertical tab on the float hinge. The tab touches the needle valve case, or some other part of the carburetor- I don't remember on your 2bbl- and prevents the float from dropping too far. The drop setting is not as critical as the float level, but the float should not go to the bottom of the bowl. There usually is a gauge in the carb kit for measuring the drop distance.

Harvester

every rochester i ever had spit it out somewhere i quess the top is as good a
place as any. philip

You may have too much fuel pressure. Put a gauge on the fuel line & check it. It should not be over 4-5 lbs. If it is dirt getting in the needle & seat, try this trick. Put a vise grip or clamp on the rubber fuel hose to block it off. Start the engine & run it till it dies or starts to die. Take the clamp off & start it again. The rush of gas will usually flush the particle through. If the first time doesn't work try again. If that doesn't work then go to plan B. It's a good idea to put an inline filter in the line between the tank & pump. Also there should be a filter in the inlet of the carb.

Thanks for all the tips, I ended up taking it apart a couple more times, each time doing some minor adjustments or cleaning. On a whim I decided to take the float completely out to really go over it, and it was full of gas! I guess I couldn't feel it when it was on the pivot. Needless to say I am an expert at taking the carb off the truck and it runs beautifully now! Thanks again!