706 282 Diesel - Governor issue?

[dhermesc]

Our 706 is getting some running time in the hay fields. As of right now it's been mowing, raking and baling while we try to get a Allis 180 and a Farmall 460 running again.

The 706 when running through the field with a light load (raking or mowing) will occasionally jump up about 100 RPM and run for a few minutes that way - then drop back down 100 RPM. Took a while to notice that it was increasing the 100 RPM because it was doing that under little to no load. It is very noticeable when it drops the 100 RPM because it's almost as if the tractor died or you grabbed the throttle and pulled it down - for just a half second or so as the RPMs drop then just continues on like nothing happened at a slightly slower speed. It does it sporadically throughout the day and only under little to no load. When the governor is kicking in while operating the baler everything runs without issue.

This is the tractor that we pulled apart to replace the head gasket and had 4 of the 6 injectors rebuilt because they were popping way under pressure. Since then its been running well with no issues.

 

[Fritz Maurer]

Sounds like you have air on the suction side of the pump. Air bubbles make them run all erratic.

 

[Dieseltech]

Sounds like injection pump repair time, IF the fuel flow/filters are good. Thats how engine will act when the retainer ring begins to fail inside, erratic speed changes without throttle movement.

 

[dhermesc]

Is that something you do?

 

[560Dennis]

Seen diesel tech at RPRU , ,good idea ,hell fix you ,up . Follow his recommendations ,youll have a total different performance tractor when finished. What I suggest!

 

[dhermesc]

Actually that tractor runs and starts really well now - operational this is a minor issue but I figured it was an indicator of a bigger issue. Sounds like it is.

To me how a diesel engine starts is a big indicator of the condition of the engine. If you have poor/leaky injectors, low compression or another issue it will be most apparent while trying to start. If you use the glow plugs for 30 seconds this tractor starts in a second or two every time. But if the injector pump is starting to go those issues will mount pretty fast.


I remember our old 560 growing up, that poor tractor was used up and in dire need of an overhaul that it never got unless the next owner did it. Glow plugs did work but it was still a bear at times to get started and letting sit on top of hill to roll start got real popular the last year we had it. That tractor was getting a 1000 hours a year on it for 4-5 years straight - that was after it had only run about 3000 hours the first 12 years of its life. Somehow my dad got a decent trade out of it when he bought our new 886. Going from an open station 560 to the airconditioned comforts of the 86 series cab was like stepping out of a Model T and getting into a new Lincoln.