5-40 Rotella Synthetic in Inboard and IO Boats?

[friendly_jacek]

Originally Posted By: SteveSRT8

Continuous high rpm operation hurts nothing in a properly maintained, healthy engine. And marine motors have reduced redlines compared to street motors.


You forget that those high RPMs are done near WOT with maximum load in a boat. It's like driving the car WOT uphill. How long would the engine last on a light duty oil?

Another analogy would be using XW20 or XW30 oils in 18-wheller in a hwy. No one sane would do it.

 

[lars11]

Steve has a definite point about tension peaks due to impact changes like smacking one in with a (non european

) clutch foot. And if you would collect data on why you switch or refurbish you marine engine vs. the car v8, you would see that it is different reasons. They don't die the same way (car engines seldom rust from the inside, haha)

In boats, you change gears more seldom and it is softer and in volvos you have the soft cone clutch that reduce this even more. And maybe if you hit a stone... (of course, neeever happened to me...)

So snapped axles are rare in boats and less shearing -due to this mechanism- too.

But the higher power output and the associated effects mentioned here still seem to make marine use more like severe use on land.