I have recently inherited an 82 F100 with 81,000 from my dad. I would like to replace the current carb. as it was rebuilt by a 19 year old with very little mechanical experience. I took the truck to a local Ford dealer and after keeping the truck for 3 weeks was told that a new or rebuilt carb. was not available for this old of a truck. I had rather not have the current carb. rebuilt. I want the truck put back to original specs (proper choke function, etc.). Any suggestions for purchasing a new or rebuilt 1 bbl. carb? One more problem, after the truck is warm and on the highway everything is great; however, once I exit the interstate and stop the engine idles rough for a bit (sort of like a missing plug). The plugs are clean and the wires are new. Could this be the carb. loading up? Once I start driving again at a moderate rate of speed it is okay. Only happens after running over 70 and coming to a stop. Thanks!

 

I think your Ford dealer is feeding you a line. If it were mine, I'd pull that carb off, take it to a reputable parts house and buy a replacement (probably less than $100). If your truck is stock, you've either got a Carter or Motorcraft 1 barrel carb...both are easy and inexpensive to replace. If you don't know which parts store to try, call a few mechanics/shops and find out who they do business with. They'll tell you who sells quality and who sells junk. Second option is rebuilding the carb yourself. Kits are cheap,less than $20, and 1 barrel carbs aren't hard to rebuild. Just work in a clean, comfortable environment (not in the house) and take your time. Let us know how it works out.

 

The rough engine idle after smooth highway driving sounds like you may have a vacuum leak. Check the vacuum hoses on the carb, also check the 2 bolts that hold the carb down...they could be loose since the rebuild was done by someone without alot of experience. I think they're a 1/2" bolt. The bolts can work loose regardless, causing a vacuum leak. Have you replaced your fuel filter? How clean is the air filter?

Check your distributor cap and rotor for cracks, carbon arching lines inside, and general wear and tear. Inspect your EGR valve and the hoses going to it.

With the engine idleling spray some GUMOUT carb cleaner on base of carb and around the EGR valve....listen for any RPM increases or smoothness of idle quality. If that happens you're sucking air and need to tighten things down.

Check your ignition timing with the vacuum line going to the distributor removed, plug it with a golf tee or tape.

And i agree 100% with tmcalavy's post about rebuilding the carb you have or ordering a new one....balony on what the dealership told you.

Best of luck....keep us posted on your findings.

************
81 F150
1 BBL carb
189,800 miles

 

Thanks for the input. Checked all and found no problems. Located a carb. specialist yesterday and after a diagnostic test found that the carb. was loading up due to a malfunction in the choke. Replaced carb. and reset timing to specs. ($300) Truck is running great. Still not use to the low gas mileage. Seems like I can see the gas needle moving towards empty whenever I start it up, but it is worth the extra bucks. Thanks again!

 

 

Jessbass,
I hope you have your problem solved but I just wanted to throw something else out there about the symptom you had i.e. rough idle after running at high speed. I have heard of the exact same thing resulting from an EGR valve sticking open after running at highway speeds so when you slow down to idle, it is still allowing exhaust gases to enter the intake causing rough idle/stalling. If it dies or you shut it off, engine vacuum goes away and that is enough to allow the valve to go shut and everything is fine until you do another high speed run. If by chance it starts up again, this may be something you want to check.

'84 F150
YFA F/B
SROD
"Ex" => Bone Stock

 

Thanks for the additional information. The rough idle after a high speed drive seems to have been cured by the new carb. However, just as the engine is getting to operating temp. and I stop at a light the rough idle returns just for a moment. Yesterday, I took your advice and turned the engine off. Once I restarted it the rough idle was gone. I replaced the EGR valve a couple of months ago (before the carb). Could be a vaulty valve? I will take off and replace "again" if needed. Thanks again.