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Sea Foam in marine diesel oil [SOLVED]

Hi, just for verification…. your Sea Foam Motor Treatment can be used in either the fuel tank or the crankcase? We are interested in trying it in our marine diesels (Cummins 260) that have not seen an oil change in quite a while with thick sludgy oil. We will have to drain through the dipstick tube…. In this case, would running the engines for an hour satisfy the 100m you recommend?

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Jim D.
Jim D.
2 years ago

Hi Carl,

Yes, Sea Foam Motor Treatment (or Marine PRO) can certainly be used in both fuel and oil!

In the oil, it will reliquefy deposits and residues so they can be drained away when you change the oil. Very good application for your use case.

Running the engines for an hour would satisfy the recommendation to run the engine 100 miles before changing oil. Note that it may take a few oil change intervals with Sea Foam added at the end to clean everything out, but it will work very well to clean up the crankcase.

Hope that helps!