All Oil is Not Created Equal

Today I was in the offices of Tri-County Diesel in Bellingham and talking with Mike Rusk about engines and engine care. Mike is a leading authority on Caterpillar engines and everyone, including myself, holds him in high regard.

The oil in the transmissions, engines and generators was changed by NW Explorations in December, and we have received the oil analysis reports. My goal was to sit down with Mike and review each of these so I have a good understanding of their meaning and implications. I have been doing oil analysis in aircraft engines for 30 years and have an in-depth knowledge in the category of high performance, high compression, air cooled engines. But I know enough to not try to translate that knowledge to the marine environment without some guidance from an experienced hand.

Among many questions we have, one is to confirm with Mike that the correct oil to use in our transmissions is single weight 30SAE. My plan is to create some plaques for each piece of equipment listing the type of oil to be used. This should make it much easier for the charter clients to pick the correct oil without having to dig into the handbook that’s onboard.

Mike confirmed “30 weight” was correct. Just in passing, I also asked if the 15W40 multi-viscosity oil used in the 3126 engines was correct. I was expected the same confirming answer. However, Mike sat up in his chair and stated emphatically, “No!”

That got my attention. He went on to explain that those oils have additives. And what Caterpillar determined some years ago is that those additives are released into the air system of the engine, then participate out onto the turbochargers and that was one of the causes of premature turbo-charger death.

In fact, Caterpillar developed a special oil just for use in the 3126 and 3116 series of engines to address this. It called CAT SEAO, Special Engine Application Oil. A name only an engineer could love.

Mike said that there is also a lower cost, easier-to-get oil that meets the same specifications called Rotella T by Shell.

Now I’m off to inform NW Explorations that they need to redo the oil change for my 3216’s with the correct oil.

I later did a Google search on this issue and found 131,000,000 entries. I only read a couple of hundred.