Oil type

[xrichard]

For those interested in oil, good reading here:

http://www.bobistheoilguy.com/motor-oil-101/

and on viscosity:

http://www.bobistheoilguy.com/puttin...nto-viscosity/

One question I have, wrt marine use, is operating temperature. Because of the unlimited supply of cooling water, we know our motors run cooler than cars when measured at the thermostat. But I'm guessing, because of the high loads and high RPM, we're likely seeing higher oil temperatures and shear forces than most cars will ever see. Which is to say synthetics might provide more value than one might think if they're dismissed because marine motors run cool.

Except for the XS550, PCM recently changed its recommendation to Castrol HD40 and 30 hour change intervals if you run your at high RPM or under high load. In the TSB, PCM references that Castrol HD40 is designed to provide greater protection against thermal breakdown....and further states the 30 hour interval provides further protection against thermal breakdown. Which indicates PCM has seen thermal breakdown problems.

I run Delo 15-40 currently, but am thinking of switching to a synthetic notwithstanding PCM's recommendation. At the very least, I'll switch to HD40 at my next change.

[JohnR]

If anyone's interested, go to

http://www.blackstone-labs.com/

and get a sample kit to send in some of your engine oil. Once they've analyzed what's going on in your engine, you can see just how good or bad the specific oil you're running is doing.

[AirTool]

If anyone's interested, go to

http://www.blackstone-labs.com/

and get a sample kit to send in some of your engine oil. Once they've analyzed what's going on in your engine, you can see just how good or bad the specific oil you're running is doing.

I'm going to read the link and see what results they provide. I use another lab and the results include a detailed list of all contaminates (including glycol, water, fuel, and metals used in engine parts, and many other products of combustion, etc.), but I don't really believe i can "see just how good or bad the specific oil you're running is doing."

For industrial applications, the lab will tell if the oil is still good or needs to be changed. Many plants regularly sample the oil and don't change it until the lab says to because of down time and the expense of the oil (large volume). But my reports always come back "time to change" even if was 2500 miles or 3000 miles. Somewhere I have the reports and can post one. I will say that for 22 bucks, they were handy to diagnose two (GM) engines with leaking intake manifolds and then prove with a sample that my repair was good and the leaks were gone.

[JohnR]

AirTool thanks for clarifying my previous statement. What I meant was more to monitor your engine health through oil analysis - adjusting change interval or diagnose impending problems from the results....which is what you said.

As for myself personally, I've never sent in a sample but I stumbled across it the other day. I've always just followed the manual but I think I'll send in a oil and transmission fluid sample the next time I change them.

[AirTool]

AirTool thanks for clarifying my previous statement. What I meant was more to monitor your engine health through oil analysis - adjusting change interval or diagnose impending problems from the results....which is what you said.

As for myself personally, I've never sent in a sample but I stumbled across it the other day. I've always just followed the manual but I think I'll send in a oil and transmission fluid sample the next time I change them.

I'm traveling and will probably forget - but I'll try to dig up some test results. I just checked the lab I use and they have a different program now.

Probably they original guys sold out for a bunch of cash.

http://www.oaitesting.com/g2047.pdf