M35A2 High Idle Issue

[Brenda]

Howdy folks,

One of the M35's I got came ready to roll. Even the batteries where brand new. Because of all that I assumed it was in tip top shape. When I went to fire it up the motor ran as if I had the peddel all the way down. I pulled the stop cable out about 3/4 of the way to get the thing down to 1,000 or so RPM. If I let the cable in just a little the **** thing would run away again. It smells like JP4 in the tank so I don't think it is the fuel. However I could be wrong on this. Anyone know why the motor would do this? And how do I get it to idle down?

 

[swbradley1]

Throttle linkage?

 

[Warthog]

It is more than likely the fuel control unit lever inside the injector pump is sticking.

We see this all the time. There are a bunch of posts about it.

Here are a few

http://www.steelsoldiers.com/deuce/78640-stuck-full-throttle-multi.html

http://www.steelsoldiers.com/deuce/72242-engine-goes-full-throttle-startup.html

http://www.steelsoldiers.com/deuce/49724-deuce-rpm-idling-too-fast.html

http://www.steelsoldiers.com/deuce/29359-m35a2c-clogged-fuel-system.html

 

[steelandcanvas]

Could the smell be spoiled diesel fuel and not JP-4? Take a look at your fuel filters and the bottom of the fuel tank. Spoiled fuel has a rusty brown color and smells like varnish. This spoiled fuel would also contribute to linkages in the IP being sticky. Take a look and come back, tell us what you found.

 

[SMOKEWAGON66]

I dont know about the linkages and throttle levers, but if it has JP4 in it, I think the engine would become a grenade...If all the throttle linkages are fine and set properly and it still runs like that, drain the tank and lines, change the filters etc, and refill with good diesel. I think JP4 could cause an engine to run away and explode so....least thats what I heard.

 

[Flyingvan911]

Pour some injector cleaner in the final filter housing to help clean the IP.

 

[91W350]

Does the pedal return or does the pedal stay towards the floor. Could be as simple as a throttle return spring missing. Along the same lines, is the throttle cable all the way in?

 

[gimpyrobb]

It is more than likely the fuel control unit lever inside the injector pump is sticking.

We see this all the time. There are a bunch of posts about it.

Here are a few

http://www.steelsoldiers.com/deuce/78640-stuck-full-throttle-multi.html

http://www.steelsoldiers.com/deuce/72242-engine-goes-full-throttle-startup.html

http://www.steelsoldiers.com/deuce/49724-deuce-rpm-idling-too-fast.html

http://www.steelsoldiers.com/deuce/29359-m35a2c-clogged-fuel-system.html

I agree, they can stick in the closed position, so they don't start, or, as what happened to me, it was stuck WFO. Take the cover off and try to move it by hand. That would be where I started, anyway.

 

[gungearz]

Check the injector pump and inspect and lube all the cables.

 

[Brenda]

Ok the springs are good. Throttle returns to close (firewall). Also internal lever seems to be moving ok as well. It really does smell like kerosene in the tank with a mix of normal gas. Not 100% sure what the USMC put in the thing when I got it. I'm almost positive there is something wrong with the injector pump. Is it normal for them to go bad after sitting for some time?

 

[gimpyrobb]

Nope. Did you take off the cover under the hydraulic head?

 

[gimpyrobb]

Found a pic. There is a lever under there that should move freely.

 

[steelandcanvas]

Take the strainer out of the fuel tank and shine a light down in the tank. Let's determine if the fuel is spoiled first. Pull the primary fuel filter and see what's going on in there. There are a lot of things to look at before you throw in the towel and say the IP is the culprit.

 

[flighht2k5]

They haven't used Jp-4 since the mid 90's

 

[swbradley1]

They haven't used Jp-4 since the mid 90's

That might be the last time they filled it with fuel too.

 

[Brenda]

Forgot about this. **** I'm working to much these days. Problem was the fuel in the tank was not what I normally run. Drained all that and purged system of it. Refilled with #2 from Shell and truck ran smooth as glass. Gave the 5gal I saved to the guys down the road that work on modern trucks to play with. They have no idea what it is either. In a clear glass container the color is sort of milky blue. Out of all the trucks I have this is the only one that had this stuff in the tank.

 

[doghead]

Found on the Intrawebs

The desire for a less flammable, less hazardous fuel led the U.S. Air Force to phase out JP-4 in favor of JP-8; the transition was completed by the fall of 1996.

[h=2][/h]

 

[Jeepsinker]

My truck runs fine on rotten diesel and rotten jp-8. I've burned around 1000 gallons of it uninterrupted by any fresh fuel at all and no problems to date.

 

[emmado22]

Why do you think it is JP 4 instead of JP 8????