Leaking diesel into oil

[Mith]

Hi guys

I have a KX71 with a Kubota V1505 4cyl diesel engine on it.

Had a call today from the guy that runs it saying it is pushing diesel into the sump oil when running.

The seals on the 4 'plungers' that bolt in the top of the injection pump have been replaced as it was leaking diesel from the top of the injection pump. That problem is solved.

Any ideas what could be causing this? Its a new one on me!

I'm not with the machine and have very limited time with it in daylight, so hopefully I can gain some ideas of things to look at to best make use of time when I am there or get the guy who uses it to check it out.

Thanks
Jim

 

[olthumpa]

mith:
There are people on here that can help you unfortunately I do not see any logged in right now.

Good luck

 

[North Idaho Wolfman]

A bad lift pump or a bad injector pump are about the only 2 ways that raw diesel can get into the engine.

 

[Mith]

Thanks guys.
It has an electric lift pump, so that rules that out.

I have more information
The engine does run on a little, it you rev it up, then drop the revs it will continue at higher revs until you put the engine under load then it will die back to idle and continue to idle until to rev it up again.

The seals that were replaced are shown as part 10 in the drawing on the link
Link
And look like the 2 o rings in the picture in the link below (note, not my engine and they dont look 100% the same, but its the only photo I could find on the net!)
Link

So any ideas what could be leaking in the injection pump, or do you think the seals that have been replaced were not right?

 

[North Idaho Wolfman]

What your describing sounds like a injector failing to close.
I would pull them out and have them serviced first, I'm not sure it will fix the problem, but a flooding injector can leak fuel into the oil when it's shut down.
Also check for a plugged return hose from the Injectors or the Pump, I've see that cause flooding and run on issues as the extra fuel has no place to go.
Yes the seals should be the #10 O-rings, if there is any issues with the body part then the O-rings can't seal.

 

[Danson Sports]

We have a similar problem on the same engine on our Jacobsen LF4677 Mower
The mower would not start, we found what we thought was water in the oil so had the head skimmed and the gasket replaced, put it back together still wont start changed all filters, lift pump solenoid etc bleed the diesel still wont start!! checked the oil and it seems to have a lot of diesel mixed in with it, this is driving me mad!!

Question 1: what would stop the engine from starting?? it turns over and wants to fire up but just wont run!!

Question 2: What could be causing the diesel to leak in to the oil ??

 

[coachgeo]

Sounds like both of you need to remove your injectors and have a shop check them. If they are way off have them cleaned and or rebuilt or replaced new. If the shop feels they are not off enough to be filling crank with diesel then your issue lies elsewhere.

For the fellow whose engine wont start and sump has lot of diesel in it. You MAY have diesel in there cause it wont start for reason such as bad compression etc. Fuel has to go somewhere that got injected in there but never got combusted. Suggest you maybe do a compression check before paying for injector inspection.