PDQ OWNERS FORUM

We have started our trip north from Cape Coral, Florida to Vermont for the summer; we're currently in Charleston, SC. The boat is running well, but I have a questions regarding engine temperatures...

We have the 75 HP engines in our 2004 Hull # 40. We have been running coolant temps below 80 degrees C (176 F) at or below 2100 RPMs. When we want to run fast, we have to run a minimum of 3250 RPMs to be up on plane comfortably. At that RPM, the engines usually run about 85 degrees C (185 F). The boat really feels better at 3400 RPMs, but the coolant temps usually get up to 90 degrees (194 F) and I am uncomfortable with that because my local engine mechanics have led me to believe that 185 is best operating temp, and that above 190 we aren't doing our engines any good.

Does anybody have any thoughts on this? Thanks!

As long as it stabilizes at 90, it should not be a problem.

hi,

we too have the 75's. the thermostat installed by yanmar begins to open at 182 and is fully open at 195. i spoke to yanmar support years ago and they told me it was to cut down on smoking. we run 3350-3400 all day long all the time. we've got 2900 hrs on the engines. you may be able to get a full open 185 thermostat but it's offset so you'll need to match exactly.