Dumb ass mechanic

[rustybucket]

Please provide some of these studies, I'm curious to learn from them.

I did find this one. It was about EMD (2strokes) on ferries that were failing. They switch to multigrade piston engine airplane oil.

http://ctr.utexas.edu/wp-content/upl...s/0_5532_1.pdf

I guess the one that comes to mind (and was easiest to find in my notes) is from Tejas Coach http://www.tejascoach.com/ddcoil.html

[racclarkson@gmail.com]

While correlation does not equal causation, you'd agree it also doesn't exclude. Having said that, I'm just reporting what I know or have first hand knowledge.

Funny thing about motor oil, though. I had a 1990 Mercedes 560C I purchased new. And forgive me, I can't recall all the particulars; the service records went with the car. The car ran like a top and, at about 60,000 miles, I decided to switch motor oils. I had always used Castrol conventional multigrade but then went to Mobile 1 of the same viscosity. Right out of the chute the car ran 10-15F hotter. I don't recall if the Mobile synthetic was spec'd by MB in '91 or '92; we just figured it was better because it was hi-tech stuff. Anyway, there was never any reason determined for the rise in temp. Pretty soon after the switch, I changed back to the Castrol, and the temps dropped right back to previous range. I put 100K on that car, and I never recall it using a drop of oil. Always bothered me.

[Boatsb]

While correlation does not equal causation, you'd agree it also doesn't exclude. Having said that, I'm just reporting what I know or have first hand knowledge.

Funny thing about motor oil, though. I had a 1990 Mercedes 560C I purchased new. And forgive me, I can't recall all the particulars; the service records went with the car. The car ran like a top and, at about 60,000 miles, I decided to switch motor oils. I had always used Castrol conventional multigrade but then went to Mobile 1 of the same viscosity. Right out of the chute the car ran 10-15F hotter. I don't recall if the Mobile synthetic was spec'd by MB in '91 or '92; we just figured it was better because it was hi-tech stuff. Anyway, there was never any reason determined for the rise in temp. Pretty soon after the switch, I changed back to the Castrol, and the temps dropped right back to previous range. I put 100K on that car, and I never recall it using a drop of oil. Always bothered me.

Thats a long time ago. I believe the synthetic oils have made significant changes in their formulation. It may not be the same today. Then again Im not using synthetic in any diesel I own so I have no experiance with it. I do have 2 gassers running amsoil and their 25K oil and filter combo. Once a year or about 7k mileson 1 and 12k on the other I change the oil.

[Scarlett]

Talk about a timely thread. Friend of mine just bought a 49 Gulfstar MY with 6-71 TI engines. I had planned to survey it for him this week, but I found out the owner just did an oil change and used Delo 400 multi grade oil in it. Told my friend to have him change to the correct oil and then call me back to reschedule the survey. Also said that one tranny would not shift into forward, I am assuming they also used the multi grade in trannys, which is ok but I bet they only filled it to the mark on the dipstick while cold, not running. If you own a Detroit you should be required to read this site. John

[racclarkson@gmail.com]

Talk about a timely thread. Friend of mine just bought a 49 Gulfstar MY with 6-71 TI engines. I had planned to survey it for him this week, but I found out the owner just did an oil change and used Delo 400 multi grade oil in it. Told my friend to have him change to the correct oil and then call me back to reschedule the survey. Also said that one tranny would not shift into forward, I am assuming they also used the multi grade in trannys, which is ok but I bet they only filled it to the mark on the dipstick while cold, not running. If you own a Detroit you should be required to read this site. John

Multigrade in tranny? Depends on the tranny I guess. Not acceptable in ZF250s in my boat.

[motoryacht lover]

My ZF 360’s require a straight weight as well

[Scarlett]

These are Allison’s and an old time Allison mechanic told me that they would run on most anything including water, I think he was joking, most people just use the same oil as the motors for convenience. By the way Ron the guy who put the multi grade delo 400 in the engines was in Oxnard. Weather this weekend looks good, have a great trip, wish I was going. John

[krush]

Many of the oils available today weren't even imagined when the specs were chosen in the owners manual for much of the equipment on our boats.

[racclarkson@gmail.com]

Many of the oils available today weren't even imagined when the specs were chosen in the owners manual for much of the equipment on our boats.

Very true. If you want to use your equipment as a test bed and report back, that’d be great. Or...the equipment may be old and the manuals out of date, but the manufacturers are still manufacturing. That would be my first choice before deviating from spec’d lube oils;e.g., straight to multi grade.

[krush]

I have cummins, and run pure synthetic diesel oil.