cummins idles high after tinkering with pump
#1
cummins idles high after tinkering with pump
Hi. I just purchased a 1993 dodge w250 with the 5spd manual transmission and of course cummins 12 valve motor. I had a hankering for more power so after doing some research i made the following mods to my ve injection pump:
1 - turned the factory fuel pin 90 degrees
2 - turned the "gear" under the diaphram in the pump 1 and a quarter turns clockwise
3 - turned the "smoke screw" on the top of the pump in a bit
4 - turned the fuel screw in until it bottomed out after removing safety collar ( no sign of a run away)
Lots of power now, however, after doing mod number 4 ( the fuel screw) the truck idles very high. I dont have a tach but it is much higher than stock. The revs dont hang though but just incase i backed the fuel screw off a couple turns out of fear the truck was on verge of "running away". This lowered the idle a bit but it is still too fast. Is there anyway to lower the idle even with the fuel screw turned up? I looked at the pump and i see two logical locations for lowering the idle - however i am wondering if it it common to have to lower the idle speed after playing with the fuel screw? If not did i mess something up?
1 - turned the factory fuel pin 90 degrees
2 - turned the "gear" under the diaphram in the pump 1 and a quarter turns clockwise
3 - turned the "smoke screw" on the top of the pump in a bit
4 - turned the fuel screw in until it bottomed out after removing safety collar ( no sign of a run away)
Lots of power now, however, after doing mod number 4 ( the fuel screw) the truck idles very high. I dont have a tach but it is much higher than stock. The revs dont hang though but just incase i backed the fuel screw off a couple turns out of fear the truck was on verge of "running away". This lowered the idle a bit but it is still too fast. Is there anyway to lower the idle even with the fuel screw turned up? I looked at the pump and i see two logical locations for lowering the idle - however i am wondering if it it common to have to lower the idle speed after playing with the fuel screw? If not did i mess something up?
#2
Registered User
Yes it is common to lower the idle after turning the full power screw. After I turned my full power screw two turns, I had to turn it down. One good thing about the other mods you mentioned, it generally wont affect the idle of the truck very much.
#3
Thanks for the reply! Wats the best way to adjust the idle? I noticed theres a threaded rod on the block side of the pump that acts as the stop for the throtle should this be adjusted (hard to reach) or can one adjust the screw on the top of the throttle on the top of the pump near the front of the truck. Both locations appear as though they would do the trick but is it better to adjust one rather than the other?
#4
Registered User
http://dodgeram.org/tech/dsl/more_power/Power_ve.htm
This website provides excellent drawings of how to turn up the pump adjust idle,etc. I had a hard time finding a tool to do it until my Dad had the bright idea to use his pocket knife to turn the screw after loosening the lock nut. Check out the page i posted the link to.
This website provides excellent drawings of how to turn up the pump adjust idle,etc. I had a hard time finding a tool to do it until my Dad had the bright idea to use his pocket knife to turn the screw after loosening the lock nut. Check out the page i posted the link to.
The following users liked this post:
Roadsterfan (11-18-2021)
Thread
Thread Starter
Forum
Replies
Last Post
Tazman
24 Valve Engine and Drivetrain
9
01-26-2010 06:38 AM
CTD2001
24 Valve Engine and Drivetrain
10
02-08-2008 07:56 PM
mx261
Performance and Accessories 2nd gen only
13
07-23-2006 10:08 PM