Throttle Sticking

[heckcreek]

Hello everybody, I just picked up an 84 M1009 CUCV and I am having an issue. When driving down the road sometimes it will have the throttle stick slightly open, I can also replicate it when I'm in park. I've replaced the throttle return spring and when it was sticking I took off the return spring and moved the throttle lever on the pump manually and it did not idle back down. I can shut the truck off when it revs like this, but I'm just worried it's going to stick in a worst case scenario. I just filled up and put some 2 stroke oil in the tank hoping it may lubricate whatever is sticking. If anybody has had this experience and has a fix that would be great. I'm not new to the Diesel world, nor 6.2's/6.5's, and I'm just hoping my new rig doesn't have any pump issues. Thanks in advance.

 

[cucvrus]

Possible bent throttle shaft?

 

[Mg84648]

You'll have to isolate where it's sticking. Disconnect the throttle cable at the IP and see if it's sticking at the peddle, the cable or at the throttle shaft like Rick suggested.
If everything looks good then its internal to the IP and time for a rebuild unfortunately.

 

[Chaski]

Is there a metal tag with a letter stamp under one of the three lid screws?

 

[heckcreek]

I operated the throttle manually on the pump, the truck still didn't idle down. I noticed this morning that when it revs up I can mash the brake pedal to the floor a few times and hold it on the floor then it will idle down.

 

[heckcreek]

I operated the throttle manually on the pump, the truck still didn't idle down. I noticed this morning that when it revs up I can mash the brake pedal to the floor a few times and hold it on the floor then it will idle down.

 

[cucvrus]

That has nothing to do with the idle that I am aware of. The brakes and the injection pump are 2 totally different systems. Unless I am missing some correlation here.

 

[Chaski]

TThere is a reason why I am asking about the metal tag is this... The metal tag designates that the pump has been retrofitted with the new style governor weight retainer. No tag most likely means it has the old style with the urethane ring that falls apart and gets into everything.

If your pump has a metal tag with an "e" stamped on it I have no idea what the problem may be.

If your pump does not have the tag your weight retainer might be coming apart and chunks of it may be causing the erratic throttle issues. If the pump does not have the E tag you could pull the top and look inside with a flashlight for chunks. If you pull the top be sure to place it back correctly with the throttle lever at idle position. There are plenty of good descriptions of how to do this on the forum. You don't want a runaway diesel.

 

[cucvrus]

Save yourself a lot or trouble and just change the injection pump. That way you know what you have and you can eliminate the guess work and the re-work. I never went wrong with a fresh injection pump. I had a few issues with the new HMMWV pump I recently installed on my M1009 but it was minor and with the turn of a few screws the issue was fixed. My advise change the pump to a fresh rebuilt one and be done with it. You will be happier in the long run. Without a doubt.

 

[welpro222]

I agree with cucvrus, I did this to my m1008 when the throttle shaft was leaking. Instead of trying to repair it, I replaced it with a fresh pump and not only did that fix my problem I it runs so much better now too. If you have the funds, replace the pump.

 

[heckcreek]

Don't have the funds currently, and the truck runs perfect otherwise. I will investigate this afternoon after work. Thanks for the advice.

 

[heckcreek]

Got home and checked the pump, no metal tag on the top 3 bolts. I guess I'm going to run a tank of b100 biodiesel after I go through this tank with 2 stroke oil. It has seemed a little better today, but I may be crazy. If that doesn't fix it I guess I will pull the pump cover off.

 

[Chaski]

If you decide to take a peek in the pump be sure to post what you do or don't find. It is easy, grab a beer, nutdriver, some solvent and rags and go for it.

 

[heckcreek]

Sounds good. I try to avoid touching ip's when possible. I have yet to replace one, and to be honest I've kind of avoided it.

 

[the skull]

Sounds good. I try to avoid touching ip's when possible. I have yet to replace one, and to be honest I've kind of avoided it.

Please don't be afraid of the IP. When you take it off, watch how you do it. It only goes together one way and isn't that difficult to bleed out. Clean the ends of the lines before you put it all back together, it doesn't take a very big speck of dirt to make them leak.

 

[welpro222]

Its easy but time consuming, i've done it 3 times on 3 different trucks.

 

[svlsmokey]

Curious if there was any resolution to your issue. I am having the same problem. Can't remember if it was a problem before I put the turbo on a few years ago. Seems like its getting worse.