Used engine oil mixed with diesel fuel.

[clyde]

that was very dry humor!
i rememer when hiring people, taking them out on a route, with a side, or rear loading truck, some, i think, thought the garbage jumped/flew into the truck by itself...clyde

 

[Woodland Hills]

i see, you don`t do your own work, you let someone else do it! waste oil also runs heaters in large shops, in some places used oil is used on dirt roads, to keep the dust down in the summer! when i was a kid, used oil was re-refined, and sold cheep in service stations ($0.25) a quart! as i said, in europe most add 10% gas to diesel in the winter! i rremember in warm states, like california, they sprayed used oil along side the roads to prevent the grass from growing!...clyde

It has been decades since waste oil was sprayed on roads or weeds.

 

[catalinajack]

There are no corrosives in oil until the TBN is reduced to the point of ineffectiveness. Oil analysis reveals the TBN. Lots of boat owners throw away perfectly good every fall out of misplaced fear. The TBN stays high for hundreds of hours. I have tested oil with 500 hours that was reported by the lab as still good to use. Soon, there will come along those who say they change the oil cuz it's cheap insurance. Remember when we all changed vehicle oil every 3,000 miles because the conventional wisdom dictated so? Manufacturers today do not recommend 3,000 mile change intervals. What makes boat engines any different?

Besides all the solids from combustion and additives in the oil, there can be corrosive acids that accumulate in the oil over time. That is the culprit in the discussion about whether to change oil before putting an engine into storage or after it comes out of storage. I think the majority would say change before storage to get those corrosive compounds out before sitting for a period of time. Sulphur in the fuel will combine with condensed water and form a mild acid which can go to work on close tolerance fuel injection components and damage them. Maybe this is not a big problem since Lepke is just centrifugeing his oil to clean the particles out but wouldn’t do anything for liquids ???

I wouldn’t burn used engine oil in any new high pressure common rail system for sure and probably wouldn’t on any system.

 

[FF]

'Manufacturers today do not recommend 3,000 mile change intervals. What makes boat engines any different?'

My Sprinter 3500 has a factory 20,000 mile oil service interval on Mobile !.

Not yet on boats . Used on cars for30+ years.