thermostat curiousity

[fairdeal]

So I may have gotten this wrong - but it seems

that the F115 used a thermostat with a lower opening temperature

than almost all other Yamaha 4-strokes


(I didn't check 2-strokes - but seemed at least some also used a 50 C 'stat)


And then found, what appears to be a 3rd temp for the 4.2L engines

comments?

[pstephens46]

It SEEMS like an inordinate number of 4.2 owners complain “of making oil”. Drives Boscoe crazy....

[robert graham]

Maybe differences in timing, compression, horsepower,etc. would cause engines to operate at slightly different temperatures for optimum operation?...

[boscoe99]

It SEEMS like an inordinate number of 4.2 owners complain “of making oil”. Drives Boscoe crazy....

What? Does not bother me a whit that any model of any brand makes oil.

Complainers of any model of any brand however are complainers.

[boscoe99]

Interesting IMO that the SHO seems to be more susceptible to making oil than does the Offshore model given that the SHO uses a hotter thermostat. But then the typical usage patterns are not the same.

[pstephens46]

What? Does not bother me a whit that any model of any brand makes oil.

Complainers of any model of any brand however are complainers.

Seems to me the biggest complainers don’’t own the motor in question. As many of the biggest proponents of the G-2 have probably never ridden in a boat powered by one.

[boscoe99]

There are many that always try and build themselves up simply by trying to bring others down. The old man on the mountain **** I suppose.

[zenoahphobic]

Thermostats are funny things, they actually work independent to the engine. All those values quoted rarely appear as anything for long or do not represent the operating temperature of the engine. E.g. Where is the opening temp of 50 and the fully open of 60 relevant, the thermostat quickly passes through 50 on its way to what? And it never goes to 60 unless the engine is overheating (not through lack of water, where then the thermostat doesn't work).

The temp characteristic are chosen by experiment rather than calculation.

I remembered a Cleveland 351 that overheated on the standard (Think 165? ) when converted to run on LPG. By putting a higher one (185?) in solved the overheating! The opposite of what one would believe!

[TownsendsFJR1300]

The temp characteristic are chosen by experiment rather than calculation.

I remembered a Cleveland 351 that overheated on the standard (Think 165? ) when converted to run on LPG. By putting a higher one (185?) in solved the overheating! The opposite of what one would believe!

It would be keeping coolant in the radiator longer, having a cooler liquid return to the engine.