quadrajet heat soak

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WFO

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My fuel pump does not have a 3rd port, and I believe those didn't come with a return at that time, I beleive GM started implementing a return in the mid-late 70s, but I don't think it would take much for a guy to add a return
You didn't say what year your Chevelle is, but my 69 SS has a return line.
 

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I can say that I have ran a lot of non-return line vehicles and they didn't have issues with heat soak or vapor lock, and I ran them in all weather conditions and elevations. I will agree with what was mentioned, your timing is probably too advanced. Wouldn't hurt to check the well plugs, and other things mentioned, but if it were me, I'd adjust the timing first then go from there.
 

77Dmax

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How many times are you pumping it before trying to start it?

Also pull the air cleaner lid and see where the choke is at with your next hot start. It should still be wide open. If it's closed than it's adjusted way too tight.
 
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Sam71395

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You didn't say what year your Chevelle is, but my 69 SS has a return line.
its a 69 malibu, sorry I should have clarified, could it be possible small blocks didn't have a return, because I looked it over pretty closely and can't find any evidence that a return line was ever there, would not take much to add one
 

Sam71395

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How many times are you pumping it before trying to start it?

Also pull the air cleaner lid and see where the choke is at with your next hot start. It should still be wide open. If it's closed than it's adjusted way too tight.
You may be on to somthing, I do recall that if it sits for a little bit (10-15min) when it's warm and I go and start it again, the high idle kicks on for about 30 seconds, so that means the choke would be closing again, I will adjust it today
 

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IF you've had a back fire, the power valve could be stuck open and is dumping raw fuel into the maniflod
 

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You may be on to somthing, I do recall that if it sits for a little bit (10-15min) when it's warm and I go and start it again, the high idle kicks on for about 30 seconds, so that means the choke would be closing again, I will adjust it today


That's probably it, your choke is way to tight. When the motor is cold you want to turn it until the choke fully closes, no more. No need to preload the spring or anything like that- just enough for the blade to close. That should get you in the park.
 

Sam71395

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Ok just got done driving it, I let it sit for about 20 minutes and went to restart it again, and it was significantly better, I still was an extended cranking time but it did not seem like it was flooded this time, this seemed like the fuel bowl was empty more than anything.
 

77Dmax

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Good deal, keep tweaking it!
 

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Yep will do, thank you all for the help
Next time you let it sit,before you crank it pull off the air cleaner,look down the throat of the carb see if it's dry,it should be That's how I discovered the problem on mine,mine was soaked,I put a return style pump on and the problem went away.
 

Sam71395

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Next time you let it sit,before you crank it pull off the air cleaner,look down the throat of the carb see if it's dry,it should be That's how I discovered the problem on mine,mine was soaked,I put a return style pump on and the problem went away.
I will do that, if I have the same problem would one of those fuel filters with a 3rd port (like a wix 33041) act the same way as a return style fuel pump?
 
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