Deuce runs only at idle

[Dr Phil]

Good day all!! I have been lurking here ever since I first got my deuce but this is my first post. I have searched for the solution but to no avail!! My problem is that my truck will only run at idle. When I push on the accelerator there is no increase in engine speed. I removed the access plate for the fuel cut off lever on the IP (fuel control unit). The lever there moves freely. By moving this lever when the engine is running I can kill the engine or conversely I can manualy increase the engine rmps. When I manualy move the accelerator linkage there is little to no movement of the lever. The truck ran fine for about 600 miles. I shut the truck off and when I went to start it it would run fine at idle but the accelerator pedal and the throttle cable had not effect on the engine rpm. The cut off cable works just fine. Any thoughts would be much appreciated. Thanks in advance

Dr Phil

 

[Tlauden]

Check for broken parts, that's where I would start... Trace everything between the pedal and where it connects

 

[stampy]

maybe the cable is off the throttle linkage. If you pull the shutoff too hard it may break the cable for example.

 

[gimpyrobb]

Did you play with the lever the throttle peddle connects to? Toward the back of the IP near the bottom of the side?

 

[DieselBob]

When I manualy move the accelerator linkage there is little to no movement of the lever. The truck ran fine for about 600 miles. I shut the truck off and when I went to start it it would run fine at idle but the accelerator pedal and the throttle cable had not effect on the engine rpm. The cut off cable works just fine. Any thoughts would be much appreciated. Thanks in advance

Dr Phil

Any chance that the spring in the diagram (#23) is broken. It is used to buffer the throttle linkage at the injection pump operating lever. If broken neither the throttle pedal or the throttle cable will work correctly.

 

[Dr Phil]

Thanks all for the replies. I did not find any loose or broken parts. The throttle peddle does move the lever at the rear of the IP. When I manualy move this lever ( the part that #22 connects to in the diagram) or when it is moved with the throttle peddle the engine rpm only increases about 100 rpm. The spring # 23 in the diagram appears to be fine. When I manualy move the lever at the rear of the IP should it cause movement in the fuel cut off lever, located under the access plate toward the front of the IP? Sorry I don't have any pics. I will try to get some uploaded. Does anyone have any schematics of the IP. I could not find any in the tech manuals that I have on CD. Thanks again to all of the great people that make this sight a wonderful place to hang out!!

 

[DieselBob]

Here's another thought. The operating shaft does not directly move the yoke in the governor assembly. There is a torsion spring (A) that absorb shock loads and transfers the rotational motion of the operating shaft (C) to the yoke through the spring plate (B). If one of the ears on the spring were to break then the operating shaft would turn but no motion would transfer to the yoke and no increase in fuel delivery.

 

[Dr Phil]

Hmmmm....I think DieselBob may be on to the culprit. I tryied removing the plate, but I could not remove the set screw on the yoke on the outside or visable side of the operating shaft. I will hit the set screw with some more penetrating oil and se if I can get the assembly apart. I will keep you updated. Thanks again everyone for the help.

Phil

 

[digitaldust]

this might be stupid , did you check the filters , fuel and Air .. ok also check the pin on the foot cable neer the IP mine fell out , and all my truck would do is idle

 

[RNorris]

Good day all!! I have been lurking here ever since I first got my deuce but this is my first post. I have searched for the solution but to no avail!! My problem is that my truck will only run at idle. When I push on the accelerator there is no increase in engine speed. I removed the access plate for the fuel cut off lever on the IP (fuel control unit). The lever there moves freely. By moving this lever when the engine is running I can kill the engine or conversely I can manualy increase the engine rmps. When I manualy move the accelerator linkage there is little to no movement of the lever. The truck ran fine for about 600 miles. I shut the truck off and when I went to start it it would run fine at idle but the accelerator pedal and the throttle cable had not effect on the engine rpm. The cut off cable works just fine. Any thoughts would be much appreciated. Thanks in advance

Dr Phil

Did this issue ever get a resolution? I am having the same issue on my 1971 M35A2. I had the IP completely removed and re installed it only to have the operating lever become in-operable when pushing in the accelerator pedal. It's super stiff and even under my own strength it's a bitch to move. All was working fine prior to removal and re-installation of the IP. The only thing I worked on was the HH, nothing else was disassembled other than removing the FDC, which was also re-installed. Is Something internal is binding?

Thanks for any help here!

Rick

 

[NDT]

I had this problem on a LDT-465-D which hasn't run in 9 years. Filters didn't help. As a last resort, I help open the throttle and beat on the injection pump with a hammer. Sure enough the engine sped up and now runs normally.

 

[DavidWymore]

Has to be in the governor between the throttle lever and the fuel control/shutoff lever methinks. Pop the top off the FDC.



LOL@NDT hammer...

 

[frank8003]

"My problem is that my truck will only run at idle. When I push on the accelerator there is no increase in engine speed. "

Study what all that does happen when one shuts it OFF and go backwards and study.

What does the govenor DO when you shut the engine down?

Have to start someplace........

 

[frank8003]

"My problem is that my truck will only run at idle. When I push on the accelerator there is no increase in engine speed. "

Study what all that does happen when one shuts it OFF and go backwards and study.

What does the govenor DO when you shut the engine down?

Have to start someplace........

maybe it went this time.....................