Automatic Choke Help!!!
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Posting Guru
Joined: Jun 2004
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From: Dracut, Massachusetts
automatic choke help!!!
i have a 78 f350 cc with a 400 and a 4spd. and i cant seem to get the choke to work right, or for that matter work at all. the previous owner replaced the carb with a new one, a factory motocraft. i allready replaced the choke stove tubes, i tried ajusting the choke, but no luck, it just opens a little bit and runs at fast idle. before i ajusted it, it was either open, or closed whichever i manually positioned it at. i ran the truck untill it got to hot to touch the radiator and it was still closed and running fast. when i ajust the choke, i turn the choke untill it closes and then i turn back untill it starts to open and then turn it back slightly. also the choke stove tubes are not tight, they just slip into the adaptors in the metal plate on the intake manifold, is that supposed to be that way? the kit is the one sold at napa. it also will not kick down when i tap the gas pedal. maybee im missing some parts? i'm really stuck now! also i do not want a manual choke, i hate them, i think they are a royal pain so thats only a last resort!
THanks Bob
THanks Bob
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Joined: Feb 2006
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From: Auburn, WA
Originally Posted by 77f2504by4
i allready posted this in the carburator forum with no responce, so...
I have a 78 F350 cc with a 400 and a 4spd. I cant seem to get the choke to work right, or for that matter work at all. The previous owner replaced the carb with a new one, a factory motocraft. I allready replaced the choke stove tubes, but the choke stove tubes are not tight, they just slip into the adaptors in the metal plate on the intake manifold. Are they supposed to be that way? The kit is the one sold at napa. Should i put some rtv on them? I tried ajusting the choke, but no luck, it just opens a little bit and runs at fast idle. before i ajusted it, it was either open, or closed. Whichever i manually positioned it at. I ran the truck untill it got too hot to touch the radiator (redneck temp guage) and it was still closed and running fast. It also will not kick down when i tap the gas pedal. Maybee im missing some parts? When i ajust the choke, i turn the choke untill it closes and then i turn back untill it starts to open and then turn it back slightly. i'm really stuck now! also i do not want a manual choke, i hate them, i think they are a royal pain so thats only a last resort!
I have a 78 F350 cc with a 400 and a 4spd. I cant seem to get the choke to work right, or for that matter work at all. The previous owner replaced the carb with a new one, a factory motocraft. I allready replaced the choke stove tubes, but the choke stove tubes are not tight, they just slip into the adaptors in the metal plate on the intake manifold. Are they supposed to be that way? The kit is the one sold at napa. Should i put some rtv on them? I tried ajusting the choke, but no luck, it just opens a little bit and runs at fast idle. before i ajusted it, it was either open, or closed. Whichever i manually positioned it at. I ran the truck untill it got too hot to touch the radiator (redneck temp guage) and it was still closed and running fast. It also will not kick down when i tap the gas pedal. Maybee im missing some parts? When i ajust the choke, i turn the choke untill it closes and then i turn back untill it starts to open and then turn it back slightly. i'm really stuck now! also i do not want a manual choke, i hate them, i think they are a royal pain so thats only a last resort!
Posting Legend
Joined: Sep 2001
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The loose fit on the tube is OK. The intake vacuum draws a metered amount of air thru the choke housing via that tube from the airhorn. The heated air heats the bimetal spring inside the housing releasing the choke. There is a short choke adjustment procedure in most repair manuals.
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Posting Guru
Joined: Jun 2004
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From: Dracut, Massachusetts
i beleive it is a 2150, but i will take a pic as soon as i can, where on the carb does it say? all i can find is it says motocraft.
i was thinking of changing to an electric choke but with a baby around the corner 70 bucks is more than i want to spend. i might have to rebuild the motor as it smokes out the tailpipe, but i havent run it much at all so it could just be the marvel mistery oil i put in the oil.
ok thanks for the info on the choke tubes. i have a few manuals, and they dont say much at all.
i was thinking of changing to an electric choke but with a baby around the corner 70 bucks is more than i want to spend. i might have to rebuild the motor as it smokes out the tailpipe, but i havent run it much at all so it could just be the marvel mistery oil i put in the oil.
ok thanks for the info on the choke tubes. i have a few manuals, and they dont say much at all.
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From: Dracut, Massachusetts
https://www.ford-trucks.com/user_gal...132320.520.390
thats a pic of my carb, its the only pic i took that actually looks like a carb and not a white blob, thats what i get for spending 3 dollars on a digital camera. if the link doesnt work, go to my gallerie, random truck parts and it should be on the end of the list.
thats a pic of my carb, its the only pic i took that actually looks like a carb and not a white blob, thats what i get for spending 3 dollars on a digital camera. if the link doesnt work, go to my gallerie, random truck parts and it should be on the end of the list.
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From: Dracut, Massachusetts
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From: Louisville,Ky.
That link doesn't show me a pic, just abunch of letters and ??????
This link works https://www.ford-trucks.com/user_gal...132320&width=2
You can buy just a choke cap (electric) and install it. Just tap into the stator wire off of the alternator to power it.
This link works https://www.ford-trucks.com/user_gal...132320&width=2
You can buy just a choke cap (electric) and install it. Just tap into the stator wire off of the alternator to power it.
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Posting Guru
Joined: Jun 2004
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From: Dracut, Massachusetts
the problem im having is the choke wont open, unless i move it to the open position with my fingers. when i depress the gas pedal, the choke closes tight, and then when it starts it opens a little bit, maybee a 1/4''. and thats it, it never moves from that position no matter how long i let the truck run. if i manually open the choke, it closes back up on its own. mashing the gas doesnt do anything either. isnt the choke supposed to open up, and stay open when i mash the gas pedal? it only opens a tiny bit with the pedal to the floor, and as soon as i let off, it closes again.
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From: Dracut, Massachusetts
Originally Posted by williamm21
Check the linkage on the side of the choke, there has got to be something stopping the plate from moving full travel....maybe a tab or perhap even a broken link.
Post Fiend
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From: Where's my map???
The thermal spring is probably adjusted too tight. The cap that holds the spring should be turned to the right. (Clockwise) I can't tell by the picture if there are rivots or screws holding it. If there are screws just loosen a little and turn to adjust. If its rivots. Use a slighty dampened rag and turn it.
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Posting Guru
Joined: Jun 2004
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From: Dracut, Massachusetts
well, i tried ajusting it, the spring has very little tension holding the choke shut. just enough i think. its not the electric choke, just the temp one. it may be that the spring is worn out, when i move the choke by hand, it seems to move freely. no major binding or anything. i beleive the spring may be bad, because it makes sence. but it doesnt seem to explain why it will not kick down. it just keeps on running fast. all my other trucks, would kick down after i pushed the gas a little bit.
Post Fiend
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From: Where's my map???
If you hold the butterfly open by hand and throttle up. That should release the high idle cam. If it does not check the adjustment for high idle. When choke is fully open and high idle cam is at its lowest lobe adjusment screw should not be in contact with lower lobe.