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How to adjust idle speed Ford 7.8l Brazilian

Problems

Member
Joined
Jun 27, 2020
Messages
20
Location
EHT
I have a 1991 ford F800 with the 7.8l engine and its barely idling at 500 rpm. Ive never had to adjust an idle speed before so i dont exactly know how to do it. I heard you can adjust some screws in the injection pump somehow, but I was wondering if it could be adjusted another (easier) way. I'm pretty sure it's supposed to be at 750.
Thanks
 

funwithfuel

Senior Member
Joined
Mar 7, 2017
Messages
5,629
Location
Will county Illinois
Occupation
Mechanic
You'll want to take a picture of that pump specifically near the throttle control lever and post it here. Then we'll have to sit back and wait for thepumpguysc to dole out a dose of wisdom.
 

doublewide

Senior Member
Joined
May 31, 2015
Messages
844
Location
MA
I don’t know the answer to your question but I was wondering, do you have an electronic fuel shut off solenoid or a cable ?
 

crane operator

Senior Member
Joined
Mar 27, 2009
Messages
8,373
Location
sw missouri
idle-speed-adjustment.gif


This is a image of one off a 12v cummins, but those are mounted on the drivers side of the engine. Yours is kind of a mirror image of this pump (everything is reversed and mounted on the passenger side), and this drawing shows the "low idle adjusting screw". Its behind the rod that comes from your foot throttle.

Its kind of hard to see in your picture, but I think its the one I have the yellow arrow on.


idle adjust screw 1_LI.jpg
 

Problems

Member
Joined
Jun 27, 2020
Messages
20
Location
EHT
idle-speed-adjustment.gif


This is a image of one off a 12v cummins, but those are mounted on the drivers side of the engine. Yours is kind of a mirror image of this pump (everything is reversed and mounted on the passenger side), and this drawing shows the "low idle adjusting screw". Its behind the rod that comes from your foot throttle.

Its kind of hard to see in your picture, but I think its the one I have the yellow arrow on.


View attachment 240699
Thank you, that did it. The trucks idling nicely at 750
 
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