Branson 4820h oil dilution

[Max24Man]

I have a 2021 Branson 4820h with a Kukje engine Ser number TX3K00116 With 290 hours it's a hobby machine kept in an enclosed garage, serviced regularly, fuel is clean, fuel bowl clean.

Here is what happened:

Recently while doing some light work
it start smoking and the engine began running at high rpms, not responding to the ignition switch being turned off. So, a few seconds later, I stalled the engine by driving it under a load.

The crankcase had about 2 gallons of fuel in addition to about a gallon of oil. So I changed the oil before cranking it again.

At this point with fresh oil, I started the engine. It ran normal with no skipping but checking the dip stick every few minutes, found the level to be gradually going up. I also observed a misting of oil and diesel mixed, coming out through the oil filler cap, after removed, located over the pump drive. Inside the pump drive it also looked "washed" suggesting oil dilution, not black with oil.
Any diagnosis ?
Also the warranty excludes the injector pump but was wondering if anyone has experienced TYM making exceptions on this part?
Thank you in advance for your time.

 

[ptsg]

If you're 100% sure it's diesel, it could be the injection pump shaft seal that must be leaking diesel. It would leak just behind that gear you see on the fill port on the timing gears case and then end up on the oil pan.

Another option is hydraulic/transmission oil from a bad shaft seal on the hydraulic pumps.

 

[oldnslo]

Does that model have a mechanical lift pump? If yes that could be leaking also.

 

[Max24Man]

Due to the thin viscosity appears to be diesel but I will check hydraulic fluid level.

 

[Max24Man]

Does that model have a mechanical lift pump? If yes that could be leaking also.

Thanks. It's electric.

 

[doneill127]

I had this happen on a tractor with a MHI S3L and it was the seal on the injection pump. Repairs were covered under the emissions warranty.

 

[mini14]

or a bad injector stuck open