120hp Lehman lube

[FF]

This result simply shows that engines DO BETTER , being run.

Every oil is about 20% addatives , that actually do work .

A nice long run like the ditch will make any engine happier, and most ant detergent oil is going to help, if changed with a new filter on time.

Most engines do run better with the lightest oil that will not depart past leaks or the rings.

So a switch to multigrade , sometimes is a help.

Personally I am a single weight fan .I care about how long the engine goes before overhaul , less about oil consumption.

Oil is cheap, engines , esp non industrial that need to be removed for overhaul , are a drag to refresh.

 

[Nomad Willy]

Thanks for your input FF and I do almost exactly what Larry does even to get it at the NAPA store. When we moved to Alaska I was happy to see NAPA had my favorite boat oil and car oil. If I was operating a big diesel truck in the winter I'd use Delo 15W40 as I would see an advantage to the multi-vis oil at start-up. That's why they developed 10W30 in the first place but as I recall they did it when we also had 6 volt batteries and cranking in the cold was an issue then. Synthetic oil was developed by the military for operations at 50 below zero as no dino oil would flow at that temperature. But in boats that are not pickled we usually keep our engine compartments heated so I see no need for multi-vis lube oil.Tom is right however, a safe place to be is to read the manual and do what they say. That said they do say or specify things in manuals that they would not, on occasion do themselves. And in manuals they specify grades of oil** ....not brands. Whenever a new product comes along they're late to recommend it in manuals. Synthetic oil and radial tires come to mind.