Fuel leaks down?

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emsherer

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My 85 K10 350 has a quarter carb. If I let the truck set for more than a week I have to crank over for 15-20 seconds to start. The fuel seems to drain down back to tank. I have tried the paper filters with the check valve and they help for a few months then fail. I have set the carb off ,filled bowl up and it does not leak down. Any ideas? Thanks
 

80BrownK10

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My 85 K10 350 has a quarter carb. If I let the truck set for more than a week I have to crank over for 15-20 seconds to start. The fuel seems to drain down back to tank. I have tried the paper filters with the check valve and they help for a few months then fail. I have set the carb off ,filled bowl up and it does not leak down. Any ideas? Thanks
I watch an old school Mopar guy on YouTube. His channel is called uncle Tony's garage. He talks about this. He said current gasoline especially with ethanol in it evaporates like that and it is just a characteristic of the new type of fuel. I have the same problem with my truck. I commented on one of his videos and he said yes that's just the way current fuel does. All his cars he said do that.
 

dvdswan

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Only way to cure this is to install an electric fuel pump and ditch the mechanical. Just don't install one that has 60 psi unless you add a regulator as well.
 

1987 GMC Jimmy

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What's a quarter carb?

Bone apple tea... Just kidding, OP.

Anyway, Quadrajets don’t store much fuel to begin with, and as mentioned, the properties of ethanol make it a losing battle. If you’re sitting for a long time, I’d switch to non-ethanol. The short shelf life of E10 gasoline in conjunction with the deposits it leaves when it sits, its corrosive nature, and its hydroscopic tendencies, make it feasible for a regular or semi-regular driver, but that’s it. If you’ve ever rebuilt a small engine carb and seen that white stuff caked on the bowl, those are deteriorated metal particles. Hell, I’ve seen it turn a brass discharge nozzle into shavings in a small engine carb.
 

80BrownK10

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Does it only work with quarters?

Is it 25% of a carb? If so you might wanna get a full carb.

Pretty sure it's a typo but, it's still funny.o_O
I was like what, and just read over... thinking I have no idea what that is, but I also am not a carb expert, so oh well.
 

82sbshortbed

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CoggedBelt75

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I run 100% non ethanol in mine. In the summer during our irrigation season she will sit in the garage as long as 2 weeks and I have to crank longer than normal to prime the carbs back up. Mechanical pump also. Was gonna put a one-way check valve before the pre-filter but not worth the 50 bucks to do this.
 

MisterB

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My 85 K10 350 has a quarter carb. If I let the truck set for more than a week I have to crank over for 15-20 seconds to start. The fuel seems to drain down back to tank. I have tried the paper filters with the check valve and they help for a few months then fail. I have set the carb off ,filled bowl up and it does not leak down. Any ideas? Thanks
I'm guessing you aren't pressing the accelerator 3-5 times to the floor and back prior to trying to start it?

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80BrownK10

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I'm guessing you aren't pressing the accelerator 3-5 times to the floor and back prior to trying to start it?

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My truck does the same thing. I can push the petal 2x or 5x. Still have to crank for more than 20 seconds or so to get it to fire. It has to pull fuel up and into the cab from tank.

Do you ever park your truck two weeks or two months at the time then go try to start it? This is what we're talking about. If I drive my truck every day or every other day it doesn't do this.
 

MisterB

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My truck does the same thing. I can push the petal 2x or 5x. Still have to crank for more than 20 seconds or so to get it to fire. It has to pull fuel up and into the cab from tank.

Do you ever park your truck two weeks or two months at the time then go try to start it? This is what we're talking about. If I drive my truck every day or every other day it doesn't do this.
So far, no. Been having too much fun driving it

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