Forum Discussion

Sully2's avatar
Sully2
Explorer
Aug 14, 2013

Genset crazies!!..??

Genset has been hard if not impossible...to start lately...so I figure it was time for total maintainence.

Changed fluids and filters etc.

Starts now BUT...when running it seems at times to stumble and sort of falter??? When running it may run smooth as silk for 1 minute...or 10 minutes but then again..up pops that stumble / falter.

Any good ideas of what to start looking at?

(8KW Power Tech with Kubota engine)

26 Replies

  • I was just reading a report on another forum about the Fuel supply pump on that same Genset being the number one cause of problems.
    Their comments indicated that a pre filter with water separator should be installed before the fuel pump!
  • JohnnyT wrote:
    Gary, Usually hard to start on a Kubota is one of two things... Glow plug or fuel issues.. Since yours starts eventually but stumbles I would change out the fuel filter..The next layer back is fuel pump. Not a common failure... The other thing you might want to check is you fuel line to see if they have been compromised.


    Fuel filter was changed along with everything else...even the air filter got pulled off and replaced
  • Sully2 wrote:
    Genset has been hard if not impossible...to start lately...so I figure it was time for total maintainence.

    Changed fluids and filters etc.

    Starts now BUT...when running it seems at times to stumble and sort of falter??? When running it may run smooth as silk for 1 minute...or 10 minutes but then again..up pops that stumble / falter.

    Any good ideas of what to start looking at?

    (8KW Power Tech with Kubota engine)

    You've changed fluids and filters so that is taken care of. You have run it enough to where it should have sorted anything of that nature out by now.

    One possibility is a small fuel intake air leak which causes a bubble of air to get into the system. The design of yours may not allow that to happen. Check fuel line for wet spots.

    Second, and more likely, cause could be a electrical control issue. You may have a contact somewhere in the control system that is momentarily not providing enough voltage and it momentarily shuts off and then quickly recovers as the voltage comes back. For this one, disconnect and clean and reconnect as many connections as you can find. Unplug and replug any computer boards, etc. Unplug, inspect and replug all plug connectors.

    Hope you find it as intermitant problems can drive you crazy till found. Having an older unit, I am well aware of the issues that poor connections, particulary poor grounds, can cause.
  • I'm no mechanic so this is a guess, but have you let it sit for long periods without running it? Fuel can go bad and gum up the inner workings which causes all the problems you describe.
  • Hey Sully, Nice to "see" you here! First thing that comes to mind is a fuel starvation problem. Since you changed the fuel filters and ruled that out maybe the suction line or fuel pump is allowing a bit of air into the system or the fuel pump itself is acting up?
  • Gary, Usually hard to start on a Kubota is one of two things... Glow plug or fuel issues.. Since yours starts eventually but stumbles I would change out the fuel filter..The next layer back is fuel pump. Not a common failure... The other thing you might want to check is you fuel line to see if they have been compromised.