RPM windup

[Delicious Clint]

Well, this MUST be fun or I wouldn't be doing it....got the electrical back up and running after a long winter (lots of work, little time) and bled the brakes and got her around the block successfully. Tried to run out to a worksite to make it a "home away from home" for a few weeks and had the excitement of runaway RPM's, no accelerator control, and engine stall when I got it in gear. Of course this happened in the middle of a busy multilane nondivided highway with non-associated personnel weaving all around me at high speed.

The engine would start back up normally, and sounded fine, but would simply wind out to about 2500 RPM. I could get it in gear and bump forward three or four feet, which would immediately cause the engine to lug down and die.

Took more than a dozen lurches to get her off the road to safety. My heart rate is another story.

Fuel injector pump? The accelerator linkage seems fine although there's no pressure or response to it. She just wants to wind up.

Pulling the engine stop slows her down but it takes a few minutes to kill it.

All thoughts appreciated -- AAA-RV got it to a shop but I want to understand this in order to talk to the mechanic.

Thanks!

 

[gimpyrobb]

Just to be sure we are on the same page, we are talking about an M109a3, multifuel motor, the engine starts and shoots to 2500rpm right away? If you happen to get it in gear and let out on the clutch, it kills the motor? What gear? I'm guessing not first?

 

[Delicious Clint]

Exactly

You are 100% correct.

 

[gimpyrobb]

Sounds like your engine shut-off valve is sticking. Pull the cover that it goes into and see if the lever in there moves freely. It should be in the 7Oclock position for off and toward the firewall is "run". If you push it toward the firewall it should snap back to the 7Oclock position by itself. It needs to move freely for the truck to run right.