Cold weather flooding

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clhyer

clhyer

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Still driving my parts car... '88 Grand Fury, 318 Quadrajet 4 bbl. During warm weather it starts and drives a-ok. During cold weather which is now setting in, when I start it in the morning it runs so rich that it acts like it's running on 5 or 6 cylinders. At noon I start it and it runs ragged, I drive to the post office (1/4 mile). When I start it there it runs fine for the rest of the day.
Any suggestions for a simple fix?
Thanks,
C
 
If it's an adjustable choke I'd try loosening it up a little. When it's cold the fuel doesn't atomize very good causing some cylinders to go rich.
 
What do you mean by "loosening it up a little"?
Thanks,
C
 
Check the vacuum operated choke pulls. The primary should set the initial air gap to about a 1/4 inch. If there is not a secondary choke pull there will be a mechanical finger that opens the air gap.
 
clhyer said:
What do you mean by "loosening it up a little"?
Thanks,
C
Click to expand...

Good catch Redfish. I forgot about mentioning the choke pull off. if it's bad it'll cause it to load up. Check that C as Redfish mentioned and if it's working here's how you adjust the choke.

Look on the passenger side of the carb at the black thermostatic choke which is mounted in an aluminum housing. It may have 3 screws around the perimiter that hold it in place. If you loosen those 3 screws up you should be able to rotate the black bakelite choke stat. It also should have lean and rich with arrows stamped on it one pointing one direction and the other pointing the other way. Turn it 1 notch lean and try it. If it still loads up keep turning one notch lean at a time until it works correctly. Note if you turn it too far the choke will not work at all. It's also a good idea to make a mark where it was originally set just in case you need to go back there for any reason.

BTW: Some didn't have screws retaining the choke stat. They had rivets. This was to keep people from adjusting them and messing up the emmissions of the vehicle. You can drill out the rivets and install self tapping screws to make it adjustable.
 
Thanks, I will look at this tomorrow evening. Going from 14 mpg to 8 really hurts!
C
 
Good luck C. Yeah that would hurt dropping that much. Since it dropped that much definitely check the choke pull off Red mentioned first. If it died that'll do exactly what your describing.
 
This is what I did last night (before reading your post). I cut a narrow piece of sheet metal about 4" long, drilled a hole in it and draped it over the air cleaner bolt, then bent it to hold open both butterflys. It was about 25 degrees here this morning when I came to work. The car stalled after I first started, but cranked right back up and drove perfect to work this morning.

I will still look at that choke pull off, but I probably won't mess with it until I've run this tank of gas through (I filled up last night). 25 degrees is about as cold as it gets here, unless we really have a cold winter...
C
 
There ya go. Sometimes those shadetree engineering tricks work good enough to get you through awhile.

BTW: Only the front butterflies are the choke. The butterflies on the rear are secondary air valve and don't act as a choke. With them held open it'll hesitate bad when you floor it.
 
You will also pay in the spark plug department. Running that rich will kill your spark plugs also . Get the choke adjusted or pay for a while.
 
Well, I filled up a couple days ago after having put the strip in to hold the butterflies open. Got about 16 mpg!!! I don't think I will be messing with the choke at this time as it is running too good...

BTW: Only the front butterflies are the choke. The butterflies on the rear are secondary air valve and don't act as a choke. With them held open it'll hesitate bad when you floor it.

HA - I haven't gone over 45 with it in months... I did floor it to see what would happen, it backfired through the carb, hesitated and then picked up speed.
Thanks to everyone that gave me tips earlier.
C
 
Could be the heat transfer on the heads and intake carbon up.when that happens the intake cant warm up fast enough thus acking as you said been there done that.Fix pull intake clean carbon out simple fix about 30 dollars if you do it yourself.
 
Snake,
Thanks for the tip. This car is only filling in for a short time until I'm ready to strip it down for parts, hopefully this spring. I will look at it at that point. Most of the driving is 1 mile to work and back...
C
 
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