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4-barrel shenanigans and locating the nexus of!

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Through an interesting turn of events, I inherited a perfectly good 302 that came out of a 1978 F-150 and decided to stuff it into a 1986 LX that my brother had…why let this good iron just go to waste?  I completed the project 6 years ago…just in time to deploy and put it in storage for entirely too long.  My deployments slowed down (a bit) last year, and I moved to a place with a garage…so now it was time for a resurrection!!
Before I parked her, I rebuilt the 302 and put a brand new Edelbrock 650cfm on top, and that seems to be the nexus of evil thus far.  Over the last few months, I have been struggling with it…here are the details:
- The electric choke is working fine, and opens and closes at all the right times.
- I was able to start the engine and it idled strong at around 1900 rpm; as it warmed up and the choke opened, she dropped to below 700 rpms and died.  I can restart it and run as long as I hammer the gas.
- Since she would not idle, I dug out the manual and tried a variety of settings on the Idle Air Mixture screws…everything from 2 turns out to 4.5 turns out.  It kept dying as soon as it warmed up and the choke opened. If I stomp on the gas, she roars along fine.  I backed out the idle speed screw and was able to hold an idle at 2000 rpm, but no amount of adjusting the Idle Air Mixture screws would hold an idle once I backed off the RPMs.
- So, I went to the auto store and replaced the fuel pump, fuel filters, vacuum plugs, and PCV line coming out of the crank.  I started her up, and it ran great!  Idled at 1900 until warm, then held a strong idle at 700…birds sang, lightning shot out of my fingers, and I turned water into Budweiser!
- Feeling like Superman, I waited a few days and then took her for a spin around the neighborhood – again she started up and held a good idle around 750 rpm once warmed up.  I drove around the block a few times, and then the engine hesitated and then stalled out.  I was able to start her back up, and by keeping my foot on the gas I limped her back into the garage.  By then she would not hold an idle at all.
- I let her cool off, and then tried to re-start again last night…nothing.  Even with the choke closed.  Aaaaah!!  Foiled again!!
- I used clear fuel filters, and can confirm that there is plenty of fuel getting to the carb.  The spark plugs look fine, and I cannot smell gas over the carb so I reckon she is not flooding.  Is there something that might have gummed up by sitting for 6 years? Any tests I can do to help?
I throw myself on the mercy of the Forum!!

Joe AZ 2 PA:
Gas does gum up over time. 6 years is a lot over time. It could be in the tank or lines. I know there are additives for putting in the gas before storage but only thing I know for afterwards is choke and carb cleaner. You may want to check with Edelbrock and ask if it would be a good idea to take the carb apart to clean any build up out and to make sure the float isn't hanging up. Not sure how much gas is in the tank but you may want to consider draining it out and putting in fresh gas with carb cleaner and starting it up. I'd get a couple of fuel filters and change them as the new gas runs thru. Also check your vacuum lines for kinks, cracks, or not fitting tightly.


Thanks for the ideas - I did put the Sta-Bil in the gas tank when I stored it, and completely drained it and put in fresh gas when I started the resurrection.  I also replaced the fuel lines just to be sure...
Perhaps taking the carb apart is a good plan.  Are there common things to look for that might be bad?

Joe AZ 2 PA:
If it's a new carb it may just need to be taken apart and given a good cleaning with carb cleaner. Don't be afraid to call the mfg. tech. support. They may give you some things to try before taking the carb apart. . . .  8)

Well, I tried to start her up this afternoon, and she ran strong under the fast idle at around 2000 rpm...and then stopped.  This time, the choke was not even open yet, and there was a small puff of grey smoke out of the primaries when it stopped.  I could smell gas when I leaned over.
So, I backed the Idle Air Mixture screws all the way out, and cleaned them off, then blew compressed air in the hole and re-seated them.  I turned them in by hand, and then out another 1.5 turns.
She runs when I keep my foot on the gas, but dies immediately after.  Is it flooding?
I will call Edelbrock tomorrow, but any advice/tips would be welcome.
Thanks much!


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