Runaway, what is it, how do I stop it?!
Welcome to Cummins Forum, odds are if your reading this your new to the 1st gen Cummins. I am going to explain what runaway is, what causes it, and how u stop it!
What is a runaway?
A runaway can occur while turning up the fuel on the VE injection pump, the reason they run away is that the control collar can't move far enough towards the "defuel" end of the plunger (making the spill port area smaller), and the backpressure in the spill port becomes high enough that engine speed goes out of control. This is why they will idle OK but then hang at high RPM. At low RPM there's not enough backpressure to start the runaway.
How do u prevent a runaway?
Simple, turn the fuel screw in with the engine running using a special procedure. With every 1/2 turn of the fuel screw, snap the throttle. IF the throttle hangs in the upper RPM's before coming back down your on the edge of runaway, or if it will not comeback down to its prior RPM, back your fuel screw back out at least 1/2 turn.
How do u stop a runaway?
Remove an intake somewhere on the engine, if your doing this by yourself, open the intake on the driver side of the engine, if 2 people, remove the intake at the turbo and give your sidekick the board to cover the inlet into the turbo. What your doing is choking the engine should the runaway occur. This will the engine down.
You need to keep a sturdy board handy while your turning up the power, after all u dont want plywood sucked into your motor at 6000 RPM's do ya?
This is runaway, and thats how u can try to prevent it, and stop it. Still want to turn uo the power??
Last edited by Cowboy_Customs; 07-07-2007 at 12:11 PM.