Hard to start after sitting a week

[Arl37]

69 C10 with a new 350 crate and new Edelbrock performer manifold and new Edelbrock Performer 4 Barrel. Also new fuel pump. After it sits for a week it spins and spins upon attempting to start. Not misses but when it starts it starts promptly and runs fine. Im pretty confident it is hard to start because there is no fuel in the carb fuel bowl and the fuel pump is having to load it up. After it starts it runs fine and starts on the first spin. Only seems to be a problem if it sits for a week. I don't think the fuel bowl should g dry after a week. What do you think?
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[GMCJOE]

Which carb are you running? Edelbrock 600 by any chance? Very common problem with it. Does it only happen if it sits for a week, or does it happen after the truck has been running long enough to get to operating temp and sit long enough to go cold again?

The fuel that we run these days is a blended fuel (10% ethanol and whatever other additives) , tends to boil at a lower temp in the carbs and evaporate.

If it truly is a lack of fuel in the carb and not needing a choke adjustment, it could be from the fuel boiling in the bowl after shut down. A phenolic carb spacer would be a good thing to install to help combat that issue.

My best suggestion though is to ditch the Edelbrock carburetor and install a Quadrajet. I have a Edelbrock 600 cfm on mine right now that I hate, but it was a good deal for the price I paid and the lack of funds for something better at the time. My issues with it are opposite though, hard to start hot and haven't installed the spacer yet to see if it solves the issue.

If you decide to swap carbs, this company seems to have a pretty good price on the Quadrajet's they sell. https://www.smicarburetor.com/products/productID/852

[Arl37]

Thanks GMC Joe. It starts up fine on the first spin if I have let it sit for only a day. Very happy with the way the Performwer works compared to 4160 Holly I first tried. Never could get Holley not hesitate on acceleration. Performer is very smooth. I dont think we have the same amount of Ethanol in our gas in California that you do in Kansas.
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[eldogg]

Check and make sure your choke is hooked up. Edelbrock's are hard to to start if the chokes not working properly.

[68gmsee]

Originally Posted by Arl37

..... I dont think we have the same amount of Ethanol in our gas in California that you do in Kansas....
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E10 is pretty much a federal mandate with some states using E15.
Evaporation, especially in the warmer weather is pretty common. I have a quadrajet on my 350 on the engine stand and if I let it sit for longer than 3-4 days I have to crank it a little longer than normal. Carb has been sealed so it's not leaking.

There's a slight possibility that the fuel pump may be the culprit and/or they do make a fuel filter with a check valve type thing in it. If that doesn't resolve and excessive cranking is a problem then you could install an electric fuel pump -turn the key on and it fills the bowl.

[Street Smart]

I think it`s in the carb, they don`t seem to hold fuel for a long period of sitting. If you had an electric fuel pump you wouldn`t see the problem but with a mechanical pump you need to crank it around a bit to get fuel up to it. I had an Edelbrock 1406 on a truck of mine for over 10 years, always did the same thing. Other then that they are very reliable.

[bonnieclyde100]

carbs have vents and the gas will evaporate after time. my truck with a quadrajet does the same thing

[bobs409]

All my cars do the same thing and I'd say after a week of sitting, most old cars will, to me it's a normal thing. (I'm used to it) Fuel possibly runs back in the line so it takes time to crank it back up to the engine.