Fuel blockage
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Instructor
Joined: Jul 2011
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From: Boiling Springs
Fuel blockage
Quick question. So im no longer getting fuel to the carb. I unhooked the fuel rail and had no fuel coming out. Then unhooked the soft line from the pump, nothing. So I figured I had some gunk in the hard lines because I’ve let the car sit out of frustration for some years. Anyway, I do to unhook the soft line at the tank, and no fuel is coming from the tank side. Question is I’d assume that the take is free floating into the line right? Like it dosent need pressure from the pump to open it up? I figured I was going to run some stuff through the lines, now I’m thinking just blow out the take fitting with some air?
Le Mans Master
Joined: Aug 2005
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From: Temple Terrace Florida
In an unblocked fuel system the fuel will flow out. You most likely have a clogged sender or sock in the tank. The tank could also be filled with sediment. I would look in the tank and do a visual inspection. You don't say what year you have, some have bladders, some do not. Once the tank problem is addressed, I would replace all the rubber fuel lines with fuel injection lines. I would flush out the steel lines to the pump. I would also keep an eye on the fuel pump including the oil in the crank case just in case the fuel pump rubber components leak fuel into the engine. Jerry
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Instructor
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From: Boiling Springs
Yeah that’s what I’m thinking. It’s a 72, tank is clean but there is some sediment at the bottom I’ll suck out. Figured I could just blow some air threw the bottom of the tank back up and clear it
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From: Im not allowed to tell you
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yes blow the line into the tank but do it gently or you may blow the sock a part. THen you may have to pull the tank to clean it but I would worry about that part latter
Thread Starter
Instructor
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From: Boiling Springs
So I shot some air through the 90 elbow at the bottom of the tank. I’m getting some fuel to drip out, but not a stream. Is there like a check valve? Should I run a pipe cleaner up it? Kind of confused why I’m not clearing it
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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No check valve, probably rust or crud thats jammed in there. I would use something that can fles but wont come apart. Not a pipe vleaner but maybe baling wire or something like that
Thread Starter
Instructor
Joined: Jul 2011
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From: Boiling Springs
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,108
Likes: 9,236
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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it sticks out, it could have crumbled and got sucked in maybe. You could siphon the tank and pull the sender with the fuel pick up out and get a better idea as to what happened
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Thread Starter
Instructor
Joined: Jul 2011
Posts: 181
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From: Boiling Springs
So the fuel sock seems pretty damn hard, like that of a shotgun shell. I shoved some wire up it and it also just stopped. So I'll get a new unite and put it in. Looks like I can do it with the tank in, so fingers crossed it doesn't fight me
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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if it goes in from the bottom, yes you can, you may want to order the tank sender tool as well just to make it easier, they are about $40 bucks,
Le Mans Master
Joined: Aug 2005
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From: Temple Terrace Florida
If the sender is like earlier C-3s and all C-2s, don't forget to soak the O-ring in conventional motor oil overnight before installing. I always installed the sender lock ring with a block of hardwood or a brass drift. Make sure the O-ring is centered in the tank indent. Fill the tank with a few gallons of fuel and let it sit. Check for leaks and fill up to a half tank, etc. I would flush all steel lines with denatured alcohol. Jerry
Safety Car
Joined: May 2001
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From: Fairfax Virginia
If you left gasoline with Ethanol (Oxygenated gasoline) in the system for a period of time the water which the the gasoline absorbed could have rusted the fuel line shut internally. It happens more often with the gasoline/ethanol mixture as it loves to absorb water which then collects at the lowest spot inside the fuel line. My 1988 C4 had that same thing happen to it. I tried blowing ~100 psi air through the fuel line and had no luck, it still had a trickle of gasoline coming out of it when the fuel pump was forcing the fuel into the line.
I filled the lines with Carburetor cleaner thinking it might have been grunge inside the line and it did nothing to help clean out the plug. Eventually the fuel line had to be replaced to get rid of the blockage. After removing the fuel line I found a rusted plug inside the pipe below the passengers seat what it had a low spot in it on a C4.
I filled the lines with Carburetor cleaner thinking it might have been grunge inside the line and it did nothing to help clean out the plug. Eventually the fuel line had to be replaced to get rid of the blockage. After removing the fuel line I found a rusted plug inside the pipe below the passengers seat what it had a low spot in it on a C4.