Throttle sticking at idle while running
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Throttle sticking at idle while running
I overhauled the 390 in my 69 F-250 and installed a new (rebuilt) 2 bbl Autoline carburetor. The problem is that when it's running the linkage is sticky and won't return to the dashpot very easily to idle down. When the motor is not running it works fine. It's well lubricated. Any thoughts on this?
Fleet Owner
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From: NorCal
Could be the throttle plates are binding/rubbing against the bores. Pull the carb and take a look... there shouldn't be any shiny spots.
You do have a carb return spring, right? Double is better by the way.
You do have a carb return spring, right? Double is better by the way.
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Thanks for the replies. Yes, the return spring is there and is a fairly stout one. I did look for another one this morning with no luck. Would the plates bind only when the motor is running? That's what has me puzzled. It all works and feels fine when it's off. It's only when it's running that it gets a little stubborn about that last 1/8 - 3/16".
It's a manual choke Mike and the fast idle isn't engaged when this is going on. I looked at that also.
It's a manual choke Mike and the fast idle isn't engaged when this is going on. I looked at that also.
Hotshot
Joined: Mar 2013
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From: Phoenix, Az.
How 'bout that pivot assembly bolted to the intake in the throttle linkage between the firewall and carb. Is it worn out? Binding? I'd get a one piece link off a Dent and delete the pivot. Hio's got some pics if you need to see what I mean.
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Interesting you should mention the one piece link Jeff. I actually found one in my old parts and almost cut it into a new piece for the pivot type linkage. When I held it next to the old linkage I saw it could work and even be more adjustable.It was a part of that pivot linkage that was hanging up but I used a welding rod and shaped a new piece instead and it's now working great. Still wonder why it only did it while running tho. I found it by disconnecting that section while it was running. I'm hanging on to the one piece linkage though- just in case! Thanks for the reply.
Hotshot
Joined: Mar 2013
Posts: 14,255
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From: Phoenix, Az.
Interesting you should mention the one piece link Jeff. I actually found one in my old parts and almost cut it into a new piece for the pivot type linkage. When I held it next to the old linkage I saw it could work and even be more adjustable.It was a part of that pivot linkage that was hanging up but I used a welding rod and shaped a new piece instead and it's now working great. Still wonder why it only did it while running tho. I found it by disconnecting that section while it was running. I'm hanging on to the one piece linkage though- just in case! Thanks for the reply.
And BTW, Welcome to FTE!
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Ford Parts Specialist
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From: Simi Valley, CA
1967/72 F100/350 V8's have a bellcrank (7A185 in upper parts catalog pic) located on the left rear corner of the intake manifold that the accelerator pedal and carb linkage connects to.
It has bushings that cannot be replaced. When the bushings wear and/or crack apart, the linkage is sloppy or binds up.
C7TZ-7A185-A .. Bellcrank Assy / Obsolete
A/T & M/T applications: 1967 F100/350 352 / 1968/69 F100/350 360/390.
CARPENTER NOS OBSOLETE PARTS in Concord NC has 1 = 800-476-9653.
GREEN SALES CO. in Cincinnati OH has 1 = 800-543-4959.
KAHOKA MOTOR CO. in Kahoka MO has 1 = 660-727-2181.
PARTS INTERNATIONAL in Farmers Branch TX has 1 = 888-727-0418.
It has bushings that cannot be replaced. When the bushings wear and/or crack apart, the linkage is sloppy or binds up.
C7TZ-7A185-A .. Bellcrank Assy / Obsolete
A/T & M/T applications: 1967 F100/350 352 / 1968/69 F100/350 360/390.
CARPENTER NOS OBSOLETE PARTS in Concord NC has 1 = 800-476-9653.
GREEN SALES CO. in Cincinnati OH has 1 = 800-543-4959.
KAHOKA MOTOR CO. in Kahoka MO has 1 = 660-727-2181.
PARTS INTERNATIONAL in Farmers Branch TX has 1 = 888-727-0418.
Double post.
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Thanks Bill and Jeff. Sorry I didn't reply earlier but wasn't aware anyone had posted here. That looks like the linkage I found in my old parts. It probably came off my old 68 that had the 240-6 in it. I held it alongside the other linkage before and it will work. I'll probably swap it out soon after reading what you've written about the other type that I'm currently using. It does seem to hang slightly still. I'm posting about yet another problem with this carb that maybe you can help with also. Thanks again for your replies- they've been very helpful!
Hotshot
Joined: Mar 2013
Posts: 14,255
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From: Phoenix, Az.
Thanks Bill and Jeff. Sorry I didn't reply earlier but wasn't aware anyone had posted here. That looks like the linkage I found in my old parts. It probably came off my old 68 that had the 240-6 in it. I held it alongside the other linkage before and it will work. I'll probably swap it out soon after reading what you've written about the other type that I'm currently using. It does seem to hang slightly still. I'm posting about yet another problem with this carb that maybe you can help with also. Thanks again for your replies- they've been very helpful!
Thank You for the closure of this thread. So many just drop it and don't tell us the outcome of their problem or question.
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I like to see them closed too Jeff. They're good sources for people having the same problem. I did it with the previous one also and started the new thread with a separate problem for the same reason- so they can be searched with the solution attached to them.
Hotshot
Joined: Mar 2013
Posts: 14,255
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From: Phoenix, Az.
ZZZACTLY! Good Job.
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