I use 15W40; diesel-rated oil.

I use full synthetic in all my engines (boat and cars). Costs more, but it's way better for the engine IMHO.

[quote=HowLin;13511]I use 15W40; diesel-rated oil.[/quote]

+1, Shell Rotella T to be exact. I use synthetic in my "good" car but we change oil so often in the boat it doesn't seem worth it. Odd that they want oil changes at 100 hours max, industrial machines work far harder than boat engines and they go longer intervals.

I use Rotella also. It is easily available everywhere. Either 10W30 or 10W40 is most available. I wouldn't even be adverse to using straight 30 weight since I don't boat in cold weather. The 100 hr recommendation is a bit conservative, probably similar to 3000 miles in your car. The oil shouldn't break down much in that period, but diesel engines produce internal soot and contaminate the oil. You can see how dark diesel oil quickly becomes.

There's an ongoing "discussion" ("argument") about whether or not synthetic oil harms older engine seals. I used it once and experienced some "weepage" around the engine oil pan, so I've gone back to regular diesel rated oil.

15-40 diesel or single weight 30 is usually available. Whatever's there in the store. I see no difference here in our climate.

I did extensive studying before I selected this one. Notice that it is specifically made for diesel engines. I called Universal and they approved it. I change my oil at 100 hours. Currenly at $ 12.00 for the 4 quarts at O'riely's ( formerly Kragen Auto). When I bought it a month ago it was $ 18.00. Notice the API CJ-4 Rating. My engine is Universal M35B.

+1

What I use and where I get it.

Rotella 14W-40 every 50-60 hours since new and Wal*Mart sells it. Cheap insurance and our engine LOVES IT and stays VERY, VERY clean.. An oil change takes me less than 20 minutes and costs less about what a bottle of cheap wine does or a six pack of microbrew..... Considering a new engine is 15k.......

Top End
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Valve cover
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Hours when pics were taken:
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I think I'll stick with what's working....

I use the 15W/40 Rotella as well.

As for old oil remaining in the sump during oil change, it is near imposible to get all the old oil out using a plastic tube extracter, I had used this method many times. When I found it time to overhaul my engine I found that after sucking out all I could after removing the oil pan there was more than 1/2 quart remaining in the sump.

I modified the oil drain plug and put and extension hose on it to facilitate oil changes. With the angle of the engine the drain plug is at the highest point in the sump. pushing plastic tube in the dip stick holes (plural) still will often not get the last of the oil out. If you go to our maintenance library you will find an article I submitted on the second page of this section. It will show the pickup tube I installed in the new sump I installed, I now get all but a few drops out of the sump.

Steve