Running stock Merc 220* oil thermostats in factory H.P. 500 remote filter blocks. Seeing oil temps around 240+ at higher r.p.m.s. with temp sender factory location in the filter block. Would like to run just a little cooler. Anybody seen or have a source for lower temp thermostats that will work in a Merc remote filter housing?

Oil is routed to filter and cooler after oil thermostat opens, so if therm opens lower than operating temp, therm is not the problem.

To get moisture out of oil system, oil temps must get to above boiling temp of water. To cool more, you would need bigger oil coolers; not diff. temp oil thermostats.

But if you change, sell me one of your merc thermostats/filter block, I need one.

Anybody got a spare merc one?

I would think that the oil goes to the filter regardless of temperature.
When the oil comes up to temp, the oil T-stat opens and allows oil to circulate to the cooler.