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  Topic Review (Newest First)
08-26-2019 04:35 AM
Tb4570
Quote:
Originally Posted by myother4x4isaCJ7 View Post
Quote:
Originally Posted by Tb4570 View Post
Actually i had that happen to me. I maxed my fuel screw out. Had a buddy on stand by with a some sheet metal to block off the turbo and gave it max throttle multiple time didnt runaway and my fuel screw was all the way in maxed out. Adjust my starwheel and backed down my idle. Thought all was good. Even made sure i gave it full throttle after everything was done before i left my buddies house. All was good got on a undisclosed county road and went to see how she would run. Redlined and ran away on my lucky i have a manual fuel shut off rigged up with a pull choke so i only had to hear her screaming for a few seconds. Backed the fuel screw off half a turn mever happened again but scared the crap out of me.
For a true runaway the fuel shutoff with the key or the cable one on the side of the pump won’t do anything to kill it. You got very lucky
I know i got lucky.But that’s interesting ive killed runaways a few times that way when messing with my pump. I thought the only way that wont stop a runaway is if its a turbo seal leak throwing oil into the intake?
08-26-2019 12:29 AM
myother4x4isaCJ7
Quote:
Originally Posted by Tb4570 View Post
Actually i had that happen to me. I maxed my fuel screw out. Had a buddy on stand by with a some sheet metal to block off the turbo and gave it max throttle multiple time didnt runaway and my fuel screw was all the way in maxed out. Adjust my starwheel and backed down my idle. Thought all was good. Even made sure i gave it full throttle after everything was done before i left my buddies house. All was good got on a undisclosed county road and went to see how she would run. Redlined and ran away on my lucky i have a manual fuel shut off rigged up with a pull choke so i only had to hear her screaming for a few seconds. Backed the fuel screw off half a turn mever happened again but scared the crap out of me.
For a true runaway the fuel shutoff with the key or the cable one on the side of the pump wonít do anything to kill it. You got very lucky
08-25-2019 10:52 PM
Tb4570
Quote:
Originally Posted by Stevenjf88 View Post
I have tons of mechanical knowledge and experience. The process doesn't make me uncomfortable at all. I just dont have experience with the power screw on this injection pump. Never seen one brought to a run away point. Wasn't sure if under towing load at WOT could present a fueling scenario that couldn't be duplicated at idle or with no load.
Actually i had that happen to me. I maxed my fuel screw out. Had a buddy on stand by with a some sheet metal to block off the turbo and gave it max throttle multiple time didnt runaway and my fuel screw was all the way in maxed out. Adjust my starwheel and backed down my idle. Thought all was good. Even made sure i gave it full throttle after everything was done before i left my buddies house. All was good got on a undisclosed county road and went to see how she would run. Redlined and ran away on my lucky i have a manual fuel shut off rigged up with a pull choke so i only had to hear her screaming for a few seconds. Backed the fuel screw off half a turn mever happened again but scared the crap out of me.
08-19-2019 06:53 PM
CJGuy By adjusting the power screw, youíre adjusting how much the pump can potentially deliver. If you ever look up a cutaway or diagram of the Ve, youíll see how the screw acts on the pump internals to adjust fuel metering. At the end of the day, the pump will only deliver the max amount youíve set the screw to. Regardless the size of the injectors. The plunger in the pump still moves the same amount of fuel, the injector doesnít change that. In regards to adjusting the throttle linkage and having a run away, never heard of that


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08-19-2019 07:59 AM
Blackduck59 On the throttle linkage it sounds like it was adjusted wrong, should not have to touch that to bring the idle down. The idle stop should take care of that.
08-19-2019 06:44 AM
Stevenjf88 Thanks for the help!

I'm trying to wrap my head around this. Run away is caused by fuel volume being to high and constant. So wouldn't bigger injectors change that? If I am maxed out on stock injectors with no runaway, couldn't larger injectors potentially cause a runaway, having to adjust the fuel screw again to compensate?
Last question, I've read where someone claimed that adjusting throttle linkage, after maxing out the fuel screw caused a runaway. The linkage required adjustment to get the idle back down. Is this something to be concerned with?
08-18-2019 07:53 PM
CJGuy They donít always run away. Iíve actually seen more that havenít with the screw all the way in than those that have. Just bear in mind your idle will increase and will have to be adjusted afterward


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08-18-2019 07:41 PM
Stevenjf88 I have tons of mechanical knowledge and experience. The process doesn't make me uncomfortable at all. I just dont have experience with the power screw on this injection pump. Never seen one brought to a run away point. Wasn't sure if under towing load at WOT could present a fueling scenario that couldn't be duplicated at idle or with no load.
08-18-2019 07:18 PM
CJGuy All those mods are part of separate systems. Adding a boost pin or governor sprig wonít affect your power screw. If you adjust it properly, and ensure the jam nut is tightly in place, you wonít have a runaway on the road if it isnít doing it on the shop floor. If youíre uncomfortable or unsure, donít do it, as you can do tremendous damage


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08-18-2019 07:02 PM
Stevenjf88
Run away when cranking up fuel

Getting ready to turn up the fuel and AFC for the first time. Truck has all of the supporting mods and gauges. I would like to max out my pump and run a fuel pin and 3200rpm spring. Future will probably be 5x12 injectors.

Question one: Do I run any risk of run away while driving the truck, even if It didnt run away while stationary? I plan to max out the pump and back off if it does, just curious if anyone has done this, only for the truck to run away moments later when you hit the road? Anything in particular I should look out for?
Question two: Will a fuel pin, spring, or injectors affect a runaway scenario? I was planning to max out the pump prior to the pin and injectors in a few months. Should the screw be adjusted again when those mods are done or does that really not affect the supply volume of the fuel screw?

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