governors & pump adjustment

[rbargeron]

Pretty sure all kubota diesel pumps have mechanical governors - all are designed to increase fuel flow to maintain engine rpm under load. It is rare, but has happened, that one of the internal governor springs either breaks or falls off it's perch, reverting the engine back to un-goverened rpm fluctuation with load.

A quick way to check if your governor is working is to drive along a road in high gear at about half throttle - notice the changes is speed, engine sound, and exhaust smoke as you go up a grade. Under normal gov. operation you'll notice your ground speed drop a little, the engine get louder and the exhaust should include a small amount of black smoke, as the engine tries to meet the increased load.

BTW, although the manuals all say the injection pump has been factory-set, I've seen two Kubota pumps that were not set for full-fuel at the max position. I adjusted both for very slight smoke at full chat - got noticeable power increase (L345 and L3050) - maybe 10%

 

[hayden]

The 3710 I used was clearly governing some because I'd get smoking etc on hills. It was more the accuracy of the governor, at least as compared to my 2910.

 

[Anonymous Poster]

I did tweek the fuel rate adjustment on my old L245DT. It always had plenty of power until I added a 5' snowblower, I could lug the engine right down without even a wif of smoke. After the adjustment I had about 15% more power and a good black haze under full load, not to mention the paint on the muffler finally got hot enough to burn off. Didn't change the max rpm though which was around 3000. Ran it for many years with no ill effects before I sold it to downsize to my BX.

 

[PaulT]

Has anyone adjusted their 2710 (or similar) for higher HP (to get the black haze at peak output)? If so, how do you do it, and when should you do it?

PaulT

 

[ronjhall]

Paul
<font color=blue>how do you do it</font color=blue>
I don't know how to do. /w3tcompact/icons/crazy.gif
<font color=blue>when should you do it?</font color=blue>
After its out of warranty. /w3tcompact/icons/smile.gif

 

[Bird]

Good answers, Ron, although I'd add after it's out of warranty and you have the money in your pocket to pay for the repairs./w3tcompact/icons/laugh.gif

Bird

 

[rbargeron]

Diesel pumps are pretty similar in operation from one model to the next - they vary in size and number of plungers (one for each engine cylinder). They have adjustable stop screws on each end - inside thimble-size metal caps. The one toward the back is for idle, the front one is the max-fuel adjuster.

Factory service manuals say these are both factory-set and are not to be adjusted. But, while large adjustments can create problems, loosening the locknut and making a small ccw adjustment of the front screw can get you a bit more power without over-fueling the engine.

The key to adjustment is to keep the full-load smoke down at a hint - if it is already there, don't adjust it. If your stack is smoke-free at full load, try a small adjustment - 1/4 turn at a time. You won't hurt anything unless you over-do it. Don't forget to retighten the locknut.