Generator Problem

[Bluewater gal]

Help! I have water in my oil in my Kubota generator...a lot of water. I had it tested and there is no anti-freeze or diesel in it, so we don't think it is a cracked block or a blown head gasket. What else can it be?

[a64pilot]

Exhaust elbow, or maybe a stuck anti siphon valve.
Or poor installation, I'd start by of course changing oil as much as it takes to get all the water out, and then close sea cock when it's not running.
If it re occurs, likely exhaust elbow and if not poor installation of siphon break maybe

[Bluewater gal]

We have not started the generator since the old oil was removed and new oil was put in. We are thinking about leaving the seacock closed and running the engine for about 5 minutes to see if there is any more water in there. The generator has 950 hours on it and we don't think it's the exhaust elbow and we're not sure where the anti-siphoning valve is. There was about 2 qts of water in the oil we originally drained. We were thinking the water may be getting in thru the raw water pump. Is that possible?

[donradcliffe]

Was the oil white and like a milkshake, or did it look like regular oil without the water whipped into it??

[Lepke]

In addition to things mentioned, I assume you're running in fresh water. No mention of salt. If the oil is cooled, the oil heat exchanger is one place oil and raw water have in common. Lots of water could mean a seal, solder joint in the exchanger failed. It depends on the pressure difference between the two in the exchanger.

[Bluewater gal]

It was thick and looked like gray Elmer's glue an in fresh water.

[DeepFrz]

Usually if the seal in the raw water pump fails it leaks outside the motor and you would see signs of the leakage. However if both seals failed and you didn't notice a leak then the water could be getting in through the raw water pump shaft. Oil cooler is a better bet if you have one.

[Bluewater gal]

Ok...thanks for the info.

[donradcliffe]

Who marinized the Kubota?? Phasor? Nextgen?? BMZ?? What size genset??

It is a puzzler, because

1. I don't think the little Kubotas come with oil coolers.

2. The milkshake means the engine was running with the water in it, which means that the cylinders weren't full enough of water to hydrolock it. Probably eliminates any problem with the exhaust elbow or siphon valve.

3. The raw water pumps are made with a water seal, then a gap designed to sling leaking water out of the pump, and then an oil seal. Because of the gap, there is not enough water pressure to overcome the oil pressure.

4. No coolant in the oil should eliminate leaking block or head gasket. OTOH, has the genset been losing coolant with no visible leaks??

[Bluewater gal]

No coolant loss at all...still full in the reservoir . I changed the oil, so what I plan to do is leave the raw water shut off, then run it for about five minutes and turn it off. I will then recheck the oil to see if it is the same level. Also it does not have an oil cooler.

[Bluewater gal]

Does anybody know whether the exhaust manifold mixing box has raw water or just antifreeze only? I am thinking that antifreeze is all that is in the manifold box, not raw water.

[DeepFrz]

The mixing elbow uses raw/sea water not antifreeze. How is your exhaust hose after running for 5 minutes with the raw water sea cock shut off? Did it smell like burning rubber?

[Greg4cocokai]

We had our Westerbeke 7.6 BTD fill the crankcase from a failed rear seal on the raw water pump.

[Diesel Bill]

All good ideas, My bet is the raw water pump seal. please let us know when figured out and fixed.
If you run the engine with sea cock closed will destroy the rubber/neoprene impeller.

[Bluewater gal]

We decided not to run it without water because we were afraid of ruining the impeller. We actually just got to the boat an hour or so ago and have turned the raw water on and are getting ready to start it...Fingers crossed!