[C2] major fuel leak
08-13-2018, 08:51 AM
#1
major fuel leak
Well...I was driving my 66 327/350 when it just died. Coasted to a safe place, opened the hood and fuel was bubbling in pools on the manifold.
This was no slight leak. It was difficult to isolate the leak as it involved the entire primary section and fuel inlet fitting.
I had the car roll backed home. Cold started it this morning...started fine...but the major fuel leak began immediately.
The Holley carb is correct to the car. Before I start pulling things apart, could it be something simple like a stuck float or blocked fuel inlet?
Sometimes I know just enough to get myself in trouble......Sure would appreciate some input....Thanks Guys
This was no slight leak. It was difficult to isolate the leak as it involved the entire primary section and fuel inlet fitting.
I had the car roll backed home. Cold started it this morning...started fine...but the major fuel leak began immediately.
The Holley carb is correct to the car. Before I start pulling things apart, could it be something simple like a stuck float or blocked fuel inlet?
Sometimes I know just enough to get myself in trouble......Sure would appreciate some input....Thanks Guys
08-13-2018, 09:01 AM
#2
Team Owner
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Probably a piece of dirt in the needle/seat.
Since you're a self admitted rookie, when you put the bowl back on, don't overtighten the screws or you can warp the metering block.
Since you're a self admitted rookie, when you put the bowl back on, don't overtighten the screws or you can warp the metering block.
08-13-2018, 09:13 AM
#3
Le Mans Master
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Stuck needle (open) caused by dirt or other. On the 3367 you can remove the needle/seat assembly and clean it off or replace it without removing the bowl.
Also Holley used a brass float on the old C2s and they are soldered together. They will develop a pin hole and fill with fuel. Easily checked once you have it out - shake it and listen for the gas to slosh around. I love the brass floats, but once they begin to leak, I just buy a new one (Some guys repair them). Check both floats (primary and secondary bowls).
Also Holley used a brass float on the old C2s and they are soldered together. They will develop a pin hole and fill with fuel. Easily checked once you have it out - shake it and listen for the gas to slosh around. I love the brass floats, but once they begin to leak, I just buy a new one (Some guys repair them). Check both floats (primary and secondary bowls).
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jerbar43 (08-13-2018)
08-13-2018, 09:49 AM
#4
Safety Car
I wouldn't start it with fuel present unless you have good insurance. A spark from the distributor and poof. The leak is more than likely a piece of debris in the needle and seat. That can be checked and repaired without removing the carb.
To check it you'll need to remove the needle and seat. I'll have to assume here you know what that is. The 5/8" nut is the adjuster for the float level. The slotted screw is a jamb screw to lock the adjustment. If you are very careful in removing the seat by only turning the nut then you'll be pretty close for reinstalling it. If you move the screw you are changing the float level. If as mentioned you have a whole in the float that would require removing the bowl.
To check it you'll need to remove the needle and seat. I'll have to assume here you know what that is. The 5/8" nut is the adjuster for the float level. The slotted screw is a jamb screw to lock the adjustment. If you are very careful in removing the seat by only turning the nut then you'll be pretty close for reinstalling it. If you move the screw you are changing the float level. If as mentioned you have a whole in the float that would require removing the bowl.
Last edited by Robert61; 08-13-2018 at 10:06 AM.
08-13-2018, 09:54 AM
#5
Team Owner
If it’s a Holley with the hanging float bowl I’d check the gaskets and “O” rings around the bowl screws. People are bad about over-tightening the bowls which causes leaks.
08-13-2018, 10:00 AM
#6
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Does this carb have side hung or center hung fuel bowls? The first thing to do is remove the air cleaner and observe where the fuel is coming from. If it’s coming out the bowl vents then the needle is open for some reason. If it’s on both, you eith got a lot of dirt in your fuel to the carb or your fuel pump or regulator (if you have one) suddenly over pressurized the fuel line.
Before you take anything else apart, hold a large screwdriver by the blade and give the fuel bowl that is leaking a couple sharp raps with the handle of the screwdriver near the fuel inlet where the needle and seat are located.
BTW, a picture of your set up is worth a thousand words.
Before you take anything else apart, hold a large screwdriver by the blade and give the fuel bowl that is leaking a couple sharp raps with the handle of the screwdriver near the fuel inlet where the needle and seat are located.
BTW, a picture of your set up is worth a thousand words.
08-13-2018, 11:14 AM
#7
Le Mans Master
Something simple to check before getting into the carb itself. First, pull the main coil wire that goes to the distributor (the big one). Next, have someone turn on the ignition as though attempting to start the car...this will allow the engine to turn over without starting. Observe the fuel inlet fitting on the driver's side front of your Holley (I'm assuming here you have the stock carb). If this fitting isn't snug or the gasket is bad you can get a fairly substantial fuel leak here. If you notice that it's leaking, you'll need two wrenches...one for the fuel line nut and the other for the fuel inlet fitting. While holding a wrench on the fuel inlet fitting, use a flare nut wrench on the fuel line nut and loosen the nut. Once the fuel line nut is loose (not removed) you can then snug the fuel line fitting. Then, re-snug the fuel line nut. Don't over tighten, just nice and snug. Now, turn the ignition back on and see if the fuel leak has stopped. It's taken me longer to type this than it will take you to accomplish it. Certainly worth a try.
08-13-2018, 03:44 PM
#8
Hey Guys....You were dead on with your advice. The needle valve was stuck open. She's running strong...no leak....all is well.
Thanks so much for your help....Regards to all....Jerry
Thanks so much for your help....Regards to all....Jerry
08-13-2018, 04:40 PM
#9
Melting Slicks
Just a couple years ago I had a holley 3367 float completely fill with fuel due to a pinhole in it.
Once it could no longer float up and down it no longer turned off the fuel coming into the bowl. Fuel would pump out of the vent tube like a sprinkler.
It was quite a sight.
Once it could no longer float up and down it no longer turned off the fuel coming into the bowl. Fuel would pump out of the vent tube like a sprinkler.
It was quite a sight.
08-13-2018, 04:43 PM
#10
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Glad to hear you fixed it, but what was the cause?
If you couldnt find find a specific cause, be very careful and watch it like a hawk.
If you couldnt find find a specific cause, be very careful and watch it like a hawk.
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Frankie the Fink (08-14-2018)
08-13-2018, 08:43 PM
#11
Safety Car
I just put a newly commercially rebuilt carb on a Model A. 3 times we put it on and took it off. It was pouring fuel. I said there's no way I'm that far off on the float level. The third time I'm holding the float and I said hmm. This £€*#" float is full of gas. Took the float out of the old carb and fixed it.