Carburetor Vent Tube

[zsuprausa]

I am rebuilding my 4160 Holley. In order to get the butterfly valve out you have to remove the J shaped vent tube at the top of the barrel. When I tried to remove the vent tube it just snapped off flush to the barrel. I believe it is just a press in. It is very light metal and they sell replacement vent tubes which makes me believe I am not the first person to mangle one. Any ideas on how to get the old one out?

Thanks,
Steve

[michael hunter]

There is no reason to remove the butterflies or vent when rebuilding the carb. That vent pipe is u shaped to direct the fuel back into the carb if the float sticks open and the fuel bowl overflows.

[zsuprausa]

Actually if you are going to soak the carburetor to clean it you need to remove the choke rod seal since it is plastic and would deteriorate in solvent. In order to get the seal out you have to remove the choke rod which means the choke plate (the butterfly on the top of the barrel) has to come out. In order to get that out the "J" tube vent has to come out. This isn't an issue on an automobile carb since the vent tube is straight up and not in the way. My issue is still getting it out since now it is sheared off.

[sybrmike]

I thought the j vents were brass, but mine are rusted so guess not. Still just thin wall metal - I'd try carefully drilling them out. A little fuel friendly sealant if you happen to overbore (they're not seeing any pressure). Good luck & let us know (possible I'll be facing the same soon...)

[zsuprausa]

I talked with tech support at SKIDIM. They said these can be challenging to get out. They suggested working a chisel with light taps under the small lip on the vent tube. That worked. The first couple taps popped it up just enough that I could work the chisel around the bottom of the lip until the tube popped up. Took about 5 minutes. New tubes are in the mail.

[beast 496]

I am not sure what type of dip tank solvent you are working with, but with over a hundered carbs cleaned in the last 30 years. I have not had to remove the choke plate or J tubes. Do you have plans on where to buy replacements? This is a coast gaurd requirement for fuel overflow. Be very carefull. Al

[zsuprausa]

Discount Inboard Marine has them. $9 a piece. If you do a complete rebuild the kit comes with a plastic "choke rod" seal. In order to get it out you have to slide out the choke shaft. The only way to do that is slide out the choke plate which requires the removal of the vent tube. I suppose you could leave the seal in place but since a new one is in the PCM rebuild kit I am replacing it. The carb is already put back together and the new vent tube should arrive tomorrow. I think some people might have thought I was talking about the throttle plates and not the choke plate. Per Holley's instructions you leave the throttle plates and shaft in place. Everything else should come apart for cleaning and rebuild.

[jwws007]

great forum, I've been wondering how to get a j tube out, and instead of a chisel, i used a large screwdriver with a hammer, and it took about 5 minutes to get out

thanks