Kohler 8OEZ water in the oil

[John Muldoon]

While out this weekend in Catalina I started the Generator and it ran well for about 10 minutes. It stopped and when I attempted to re-start in ran for 10-15 seconds and stopped. I checked oil level and found a milky grey fluid. The antifreeze and water levels were all good. When I returned home I drained all of the oil out and refilled with fresh and again after a short start of the generator it was a milky grey again. This appears to be salt water as the antifreeze and fresh water levels remain good.

I serviced the heat exchanger recently and also did fuel and oil filters.

Where would the saltwater come in contact with the oil?
Could it be the heat exchanger?

Any help is much appreciated.

Topic

[Rob Schepis]

Are you, changing the filter with each flush? Running the engine? Have you gotten it to full operating temp yet? (The oil takes longer to get to temp than the coolant does.). In your pics it looks like you have good access to pull the rocker cover. I would do that to check for condensed moisture in the overhead.

[John Muldoon]

What is the best way to remove the contamination from the engine? I used some diesel fuel and drained if several times but still have the grey milky residue in the oil. I have run 2 fresh courts of oil and then drained it 3x. Is there a faster more efficient way?

[Rob Schepis]

Excess cranking means continue to crank the starter (turn the engine over) without it running. The cranking would allow the seawater pump to push seawater through the circuit and flood the muffler. Without the exhaust pressure expelling the water out of the muffler the system would flood. the muffler drain should be at a low point on the side, hopefully facing in a direction you have access to. Here’s an example.

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John Muldoon

[Gene Fuller]

Check the vacuum breaker shown in the last two photos. If that little device on the top of the hose loop is clogged the engine can suck seawater back into the manifold as the engine cools.

This can happen even if the overall design of the exhaust system is OK. Common concern for the smaller engines used on sailboats.

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John Muldoon

[John Muldoon]

What are the steps to check the wet exhaust for some type of failure?
Where is the muffler drain?
I do not close the seacock when not using the generator as it also feeds the wash down pump.
I believe the elbow is correctly positioned.

[John Muldoon]

What is excess cranking?

[Rob Schepis]

No. The exhaust manifold is coolant jacketed, not seawater.

The seawater goes three places: Seawater pump => Heat Exchanger => Exhaust Mixing Elbow.

You’re first sentence in your reply to me is likely your answer. Read that and my initial post again…………

[John Muldoon]

I do have a lift muffler and excessive cranking. I pulled the heat exchanger and of course it was good as coolant and raw water was separate and in good shape. Not sure where the salt water would come in contact with the oil as I’m not aware of a oil cooler on this model. could it be in the exhaust manifold somehow?

Some additional pics attached.

[Rob Schepis]

My 5EOZ does not have a seawater cooled oil cooler and I assume neither does your 8EOZ. Through the heat exchanger would involve the coolant but you advise that the coolant is normal. Sounds like it took it in via the wet exhaust. Do you have a lift muffler? Did you do any excess cranking recently without pulling the muffler drain or closing the seacock or pulling the raw water pump belt? If so, You could have filled the muffler and flooded the engine if the system isn’t inherently safe with the engine elbow higher than the lift muffler discharge.

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