Sticky carb float. What to do?

[Cannoball888]

My Holley 650 double pumper has been flooding the engine lately. A really bad episode happened today. I really got on the gas at a light then when I let up at the next light, the carburator stalled the engine by flooding it. And what a flood it was. When I popped the hood the top of the intake manifold was covered with fuel. I then tried to start the engine but it was still flooding. I took the air cleaner off and while trying to crank the engine I could see fuel being spewed from the primary jet all over the place. I opened the access screw to the primary bowl and fuel poured out of the opening. I then stuck in a swizzle stick and jiggled the float up and down then closed the screw hole. The car started up normally and I drove it home with no problems. I don't want this to happen again. Do I need a rebuild? The carb is not even a year old. Is it just dirty, or is something bent? I'm a noob at carbs, so any advice would be helpful.

 

[wild70stang]

for your dirt prob, if dont have it already, spray it with carb cleaner and GET A FILTER. other than that I am a noob at it too

 

[latamud]

Pull the needle and seat out of the bowl. You probably have an obstruction in there. You'd be surprised what one little grain os dirt or a metal shaving will do. You might want to pull the bowl and clean it out and run/replace an inline filter before the carb. If there isn't anything visual between the needle and seat hit it with brake clean or an air tip. Before reinstalling it, take a screwdriver and hold it backwards. Tap the handle lightly to seat the needle. If there is a minute gap there it could cause the flooding.
The way it works if the float rises, pushing the needle shut when the bowl is full. If the needle doesn't close all the way, the bowl over fills and you get all that fuel gushing out.

 

[Edbert]

There's only four small bolts holding each bowl on, take them off and clean everything out, including the needle valve and seat. Replace the gasket and don't over tighten. It is hard to imagine a year old carb is junked up unless you still have the ~40 year old tank and fuel lines. Do you run a fuel filter? Do you check it often for debris?

 

[Cannoball888]

It is hard to imagine a year old carb is junked up unless you still have the ~40 year old tank and fuel lines. Do you run a fuel filter? Do you check it often for debris?

I just bought the car less than two months ago. The gas tank looks original but in great shape. The fuel line looks like new stainless steel. There is no fuel filter between the pump and the carb, but isn't this where it should be? I don't think it would be between the tank and the pump, but I'll look for one there tomorrow when I take the bowl off for cleaning.

 

[thehueypilot]

Could also be too much fuel pressure if someone installed an aftermarket full pump that's putting out more than 7.5 psi, but most likely dirt.

 

[D.Hearne]

I just bought the car less than two months ago. The gas tank looks original but in great shape. The fuel line looks like new stainless steel. There is no fuel filter between the pump and the carb, but isn't this where it should be? I don't think it would be between the tank and the pump, but I'll look for one there tomorrow when I take the bowl off for cleaning.

If there's no filter in the line, that's your problem. See my previous thread "A TIP FOR THOSE WHO ARE CARBURATIONALLY CHALLENGED" You need at LEAST one filter, two's even better. There should also be a "rock" filter in the bowl inlets. Take the carb off the engine and then remove the bowls for cleaning. When you remove the fuel line, you should see the rock filters in the bowl(s) Unscrew the large fitting to remove them for cleaning.

 

[Edbert]

I like using the filters with the clear glass on them, allows for a very quick visual inspection. Also do not discount the possibility that you are introducing gunk and junk from the gas station's equipment and tanks, particularly if it is an old gas station or their underground tanks are low at the time.

Just because the tank and the lines look good on the outside has nothing to do with the condition on the inside. I helped pull a relatively shiny tank out of a friends coupe that was only 31 years old a while back. I pried it open for grins (do not use a cutting wheel to do this if you like your eyebrows!) and you would not beleive the gunk and junk in there. I was suprised it ran at all, at least an inch of thick sticky brown paste on the bottom, plus another 0.25 of less thick goo that looked and felt like syrup. Age and gasoline are a terrible combination. We immediately replaced all the fuel lines too.

When I started my project, new tank and lines were at the top of my list, right along side all the brake plumbing.

 

[D.Hearne]

Also do not discount the possibility that you are introducing gunk and junk from the gas station's equipment and tanks, particularly if it is an old gas station or their underground tanks are low at the time.
.

Actually you're wrong here. The level in the tanks have nothing to do with the pump sucking the "gunk & junk" from the underground tank. The inlet pipe is at the same elevation above the tank floor, no matter how much fuel's in there. You MIGHT get more than you want, if the tank was low, and there was a fuel delivery made right before you tanked up. The fuel dropping into the tank from the truck would stir up the crap on the tank bottom if the level was low enough before the drop, in that case the filters on the pumps (some have em, some don't, others never bother changing them regularly) should catch that stuff. Some stations keep their tanks full with daily small deliveries to keep their tanks full,(this also helps keep ground water out, if the tank leaks and the tank where it belongs, in the ground if the water table is high) some wait til the last minute to order fuel (and let it run out before the truck gets there and then ask the driver "where the hell you been ?" )

 

[Edbert]

Thanks for the correction, no sarcasm at all.

I was going to ask how you know so much about the insides of the underground tanks but then figured I might not want to know.

 

[D.Hearne]

Thanks for the correction, no sarcasm at all.

I was going to ask how you know so much about the insides of the underground tanks but then figured I might not want to know.

I'm a "Tanker-Yanker" Been hauling fuel for a year and a half now. Hauled food grade liquids for 12 years before that. Been driving trucks for almost 30 years now.