Carb help please

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FrobiOne

FrobiOne

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I changed my manifold gasket and replaced my cracked exhaust and now my carb is doing crazy stuff. Is there a member on here who is a carb guy that could help?

My carb is spraying gas straight out the top. I'm wondering about the throttle and choke linkage. Nothing has changed so not sure what could have caused it.
 
check for dirt in the needle and seat. Take them out, clean them, then reinstall it.

Sounds like a piece of dirt stuck in the needle and seat..
 
It might be just a tiny bit helpful to know what we're workin on here.
 
To help explain, dirt / derbies get in the way of the needle sitting in the seat to close off fuel flow into the carb bowl. The carbs vent is allowing the gas to escape. The fuel pump is just pumping away without restriction or very little restriction.

Sometimes, you can sack the carb with a hammer to free it up. Sometimes not.
 
It's a holly carb model 1920. I only use hammers to drive nails. Thanks for the tip.

I'm not carb savy. Can I just clean it out with carb cleaner or do I need to disassemble it?
 
The needle and seat is the only thing I took apart so I could powder cost the fuel hardline. I'm positive that's the problem. Can it be purchased separate from a rebuild kit? Guess I'll try cleaning it firs
 
FrobiOne said:
It's a holly carb model 1920. I only use hammers to drive nails. Thanks for the tip.

I'm not carb savy. Can I just clean it out with carb cleaner or do I need to disassemble it?
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it wasn't a joke , hammers work as long as you aren't pissed at someone
 
Take the top off and take the needle/seat out to make sure there isn't a string of shaved fuel line or something causing it to not seat.

Every once in awhile you can even get away with just pinching off the fuel flow until it runs out of fuel and then let it flow again.
It rinses out the needle and seat (sometimes)
 
Needle and seat look clean took the float bowl off and the gunk in there is pretty bad. I'm not sure that replacing the needle and seat would do much as it seems like a pretty basic system, how could one tell if it's faulty visually?
 
FrobiOne said:
Needle and seat look clean took the float bowl off and the gunk in there is pretty bad. I'm not sure that replacing the needle and seat would do much as it seems like a pretty basic system, how could one tell if it's faulty visually?
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clean and look at needle/seat closely , for any indents or imperfections that might prevent a good seal. I would just douche the whole thing real good, as long as the gaskets, needle and seat are decent, you should be ok.
 
73AbodEE said:
clean and look at needle/seat closely , for any indents or imperfections that might prevent a good seal. I would just douche the whole thing real good, as long as the the gaskets, needle and seat are decent, you should be ok.
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You can lift the float to close it and then blow through the inlet also.


A "hammer" ?
Really?

I use a rock on my bike. :D
Almost every time it's been sitting for a couple of months it over flows when I turn the fuel on, so I have gotten used to having a rock handy when I first fire it.
Couple of taps on the bottom of the fuel bowl and good to go.
 
TrailBeast said:
A "hammer" ?
Really?

I use a rock on my bike. :D
Almost every time it's been sitting for a couple of months it over flows when I turn the fuel on, so I have gotten used to having a rock handy when I first fire it.
Couple of taps on the bottom of the fuel bowl and good to go.
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you know, hammers , wrenches , ratchets , anything that will make a good thump lol
 
When everything is clean and the problem isn't resolved replace the needle and seat?
 
FrobiOne said:
Needle and seat look clean took the float bowl off and the gunk in there is pretty bad. I'm not sure that replacing the needle and seat would do much as it seems like a pretty basic system, how could one tell if it's faulty visually?
Click to expand...

I just rebuilt a 64 Carter BBS and the rebuild kit was something like $13 from Rockauto. THIRTEEN BUCKS!!
It included a new needle, seat and gaskets. Actually the seat is the brass fitting that the fuel line threads into. If you have gunk in the carb, take it off and rebuild it which includes checking and cleaning all the little passages. Download a FSM if you need directions other than what's included in the kit.
 
I think you must buy the whole rebuild kit to get a new needle. I don't think the seat (inlet fitting) comes in a kit. Most Holley 1920's used a plastic float. They get gas-logged over time and don't float anymore. I think they come in some kits. For sure get the gunk out of the bowl. If it clogs the main jets, it will run lean. The funky rubber diaphragm w/ long spring is the "economizer". At idle (high intake vacuum), it should be up. At higher throttle (low vacuum) it drops and pushes open 2 balls that let more fuel flow. If ripped, it will always run rich. Main problem with the 1920 is the sealed metering block that affects idle. It can get clogged and can't be opened, making a lean idle. Some here blow air thru from the bottom to clear it. Many rebuilt 1920's are clogged.
 
FrobiOne said:
I changed my manifold gasket and replaced my cracked exhaust and now my carb is doing crazy stuff. Is there a member on here who is a carb guy that could help?

My carb is spraying gas straight out the top. I'm wondering about the throttle and choke linkage. Nothing has changed so not sure what could have caused it.
Click to expand...

You might of set your float level too high
 
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