yes . water t stat . deffinately didn't expect those engines run that hot . im glad my alarms let me know . caught it instantly . it really jumped up quik . . . yikes

Let me see if I can add to the confusion. Most mercury applications are measuring temps after the cooler as it enters the block. That would explain why they want a relatively low temperature, it's a lot hotter in the pan. A couple of posters mention they were measuring temp before the cooler, hence they get a higher number. If you compare the temp reading on the gauge to that of a gun you quite often see a large difference. Where are you reading with the gun? Pan or filter before the oil is cooled perhaps? Gauge isn't wrong. It's reading cooled oil. Just more food for thought...carry on.

Bob Lloyd
Full Throttle Marine

ys

thanks .ill c my strainers . I get 17 to 23 wide open . both gauges seem to be very close though

just thinking here lookout . on a restriction would water pressure surge or sufer ? id say surge higher but id rather know for sure lol sorry for the triple post

In my experience higher when it is after the thermostat. I.e. blockage from an obstruction in thermostat housing, or which is often the case, risers. Your making power = heat, so optimum flow may be a lower pressure. My theory is more flow which obviously means less pressure. Or, just enough pressure to register on the gauges to alert me of flow or lack thereof. The only consequence to this maybe to much water in exhaust for a marginal cam profile.

Is anyone getting oil temp from the pan? If so, what temps. I have an extra oil temp gauge and think I'm going to run one on the pan and after the cooler...

220* F is indeed the max oil temp as stated in the Mercury 525 service manual. My understanding is that ideal temp is low 200s and under 220. I use an infrared heat gun to check mine and it's never hit 220* I shoot the oil filter and the pan. I also feel the filter after a hard run to make sure it isn't sizzling hot.

Something that doesn't get mentioned much, if at all, as everyone worries about oil viscosity thinning as the oil get's hotter is: valvespring pressure. As a spring get's hotter, the psi lessens. Springs create a lot of heat and oil is used to cool them.

Edit in: See Page 17 of the following;
http://www.racingsprings.com/Multime...b/kb513102.pdf

^^ Im glad I got some spring oilers