The truck is not driving right. I had it sitting for 7 or 8 months before starting a new job that I drive 120 miles a day to and from. I have about 7 or 8 thousand miles and one year on the rebuilt carburator and engine.

First the truck often has trouble starting in the morning. After start, the high idle does not kick in like it used to. It recently would high idle at odd times like at 65 mph when warm. Now no high idling at all. The truck wants to die at every stop. Just climbing a hill causes major jolting back and forth and the power surges from very little to normal at quick intervals. The truck gets bad milage. 8 or 9 mpg- used to get 10 mpg. Maybe rich?

Do i need a professional tune up or can I do it? Maybe the vacuum lines are damaged? I was wondering if someone knew where to find a vacuum line diagram and recommend a carb book.

 

Kevins70, One thing to try is to spray clean the carb linkage. Sounds like the linkage is sticking causing the carb to run rich.

next, can you tell us what kind it is? that may narrow down what to do next, like 2bl...4bl holley ...stock ...etc.


__JOHN__Õ¿ö
FTE Club #7
Member-
http://www.cruisin-north.com/
Santa Rosa, Calif.
72 F-250
ICQ#6030753
http://www.ford-trucks.net/users/jbhf250/
https://www.ford-trucks.com/pictorial/big/1972_f250_2.html

 

I don't know what it is about gasoline nowadays, but if you leave it in a vehicle for more than a few months it really screws up the fuel system. If you have an original ford carb with the power valve, it is probably rotten and gummed up making it run rich. Your accelerator pump diaphram probably dried up too and now is not working the best either. You can get a carb kit and a can of spray and clean it out. Just take the top off- don't get carried away and tear the whole thing down-it shouldn't be necessary. Replace the float needle and all the diaphrams and gaskets and it should fix it.

 

Kelvin, I'm assuming the 390 in a Truck is a 2BBl.
I seem to remember having that trouble with one of my Fords.
I finally had to take the Carb off, and clean it real good with 'Carb & Choke' cleaner,and drill out the old chimney and put a new one in from a Kit.
The Problem was in the Automatic choke, and the little Chimney for the Choke.
You'll need some thin hard stainless wires to get all the carbon out of those tiny holes.
Be sure the Choke Piston,and that whole choke assembly is cleaned to a Tee,and works 'Rattle Free'. The gasket has to be good because there is Vacuam pulling hot air up from the intake manifold.

Check your Vacuam lines, and use a Vacuam guage to check for leaks. That will cause the same thing. I hope you dont have a burned valve? Do you have any backfiring, or spitting? That's where all the carbon in the Carb comes from.