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Old 06-19-2019, 10:17 AM   #1
blazer2007
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funny fuel problem,need suggestions

80 chev truck stock 350/350 with headers ,performer intake and 4106 edelbrock carb. Everything new in the last 5 yrs. It,s starting to get warm here 32 degrees Celsius about 90 F. Here,s what happens, start truck in the morning,let it warm up abit and go and a minute or 2 of driving it runs out gas . Sometimes you can catch it and pump the gas while driving if not I put in neutral and start it right up no problems, no pumping just click vroom . Then it,s fine all day. It seems to do it from warming up to before full operating temp. After that is fine. Did this a couple tears ago for abit . It doesn,t do it every day but when all the conditions are right it does it but what conditions I don,t know. I,m thinking some sorta vapor lock or low idle mix, gas cap ? Single line to gas tank if that means anything
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Old 06-19-2019, 10:21 AM   #2
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Re: funny fuel problem,need suggestions

I'm certainly no expert, but I see no mention of a carb spacer. I might suggest getting one of those phenolic carb spacers and install it, potentially eliminating the heating of the carb/fuel. Have you checked the fuel pressure? It's been mentioned many times that Edelbrocks don't like a lot of it, maybe 5-6 psi. The single line shouldn't matter much. That's how my truck was plumbed too.
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Old 06-19-2019, 10:57 AM   #3
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Re: funny fuel problem,need suggestions

I don,t see why I need a carb spacer, It does this before operating temp. It does have a thicker gasket with some sorta heat transfer ability
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Old 06-19-2019, 11:27 AM   #4
1976gmc20
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Re: funny fuel problem,need suggestions

Automatic choke ???
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Old 06-19-2019, 12:31 PM   #5
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Re: funny fuel problem,need suggestions

Just a cold intake.
At the right low morning temp near 10C and higher humidity(moist air) the result is fuel puddling in the intake. The fuel vapor cools when in contact with the plenum and reverts back to a liquid state. Your motor runs lean and quits. When you start it back up there’s enough air/fuel vapor flow to keep it running and usually clean out the excess fuel in the plenum.
Next time it does it make note of the temp and humidity.
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Old 06-19-2019, 08:56 PM   #6
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Re: funny fuel problem,need suggestions

Geezer, Makes sense .I remember my dads dodge truck from the 80,s and was a 318 and if rained at night it was hard to keep running for the first 15 or so minutes in the morning. Anyway was cooler this morning and no problems . Seems to be the opposite ,warm nights , temp didn,t drop below 14. C those nights and that,s when it acted up. Wonder if the gas tank might be creating some vapor at night on high night time temps. Gas tank is never full ,maybe half at the most.
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Old 06-19-2019, 08:57 PM   #7
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Re: funny fuel problem,need suggestions

Quote:
Originally Posted by 1976gmc20 View Post
Automatic choke ???
no choke ,is just summer truck
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Old 06-20-2019, 11:03 AM   #8
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Re: funny fuel problem,need suggestions

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Originally Posted by blazer2007 View Post
I don,t see why I need a carb spacer, It does this before operating temp. It does have a thicker gasket with some sorta heat transfer ability
It was just a suggestion is all. My Edelbrock ran a little bit better after I installed one. It's better insulation than just a gasket.
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Old 06-20-2019, 09:00 PM   #9
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Re: funny fuel problem,need suggestions

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Originally Posted by Rickysnickers View Post
It was just a suggestion is all. My Edelbrock ran a little bit better after I installed one. It's better insulation than just a gasket.
Thanks , I hope my message didn,t sound bad. I have used them before on other engines but I don,t think I need one in this case. I really don,t like this Eddy carb to be honest. Buy the carb ,but oh, you need this and this to make it work.$$$$.
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Old 06-20-2019, 10:29 PM   #10
1976gmc20
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Re: funny fuel problem,need suggestions

Quote:
Originally Posted by blazer2007 View Post
no choke ,is just summer truck
Well, it just sounds like your engine is having trouble with the transition between running cold and running warm/normal.
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Old 06-20-2019, 10:37 PM   #11
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Re: funny fuel problem,need suggestions

If you have a working Delco THERMAC (thermostatic air cleaner system) on the air horn, with the damper pipe connected to a stove around the exhaust manifold, it tends to alleviate the intake icing somewhat.
It really gets exciting if the throttle butterflys ice up.
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Old 06-21-2019, 09:12 AM   #12
blazer2007
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Re: funny fuel problem,need suggestions

Quote:
Originally Posted by 1976gmc20 View Post
Well, it just sounds like your engine is having trouble with the transition between running cold and running warm/normal.
I,m starting to think so too ,just like my Dads old 318 dodge truck, it would stall when it was moist or foggy in the morning
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Old 06-21-2019, 10:30 AM   #13
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Re: funny fuel problem,need suggestions

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Thanks , I hope my message didn,t sound bad.
No worries, I hope you get it worked out.
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Old 06-21-2019, 02:54 PM   #14
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Re: funny fuel problem,need suggestions

Mine did the same thing except around 40~60*F and high humidity. Fixed it when I replaced the temp sensor in the THERMAC system that had failed open. It already had the carb spacer on a performer manifold with 1405 eddy carb.
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