Re: no thermostat??force 85hp
Well, if you are running the engine in the winter in 30 degree water, it is important to restrict water flow and thus keep the engine at optimal operating temperature.
If you are running in 70 degree water?
You need to understand the water flow path in these engines.
First, all water from the pump passes around the exhaust chest because without it exhaust gases would burn through. Then this same pre-warmed water passes around the cylinders and through the head. With a thermostat, the water is regulated to keep both the upper cylinder walls and head WATER at 160 degrees. This does not mean the head and walls are 160
Without a thermostat, full water flow cools the head and cylinder walls water below 160--how much? I never measured. How warm or cool would the head and walls themselves be? I never measured.
Although the pistons are machined oval to account for uneven heating and expansion, (they become circular at operating temperatures) they are primarily cooled by the fuel/air mix ingested into the crankcase--not by the cylinder walls and head. And there is no cooling below the ports. So only the combustion areas are cooled.
But just as an automobile engine will run quite happily and without harm with no thermostat, (of course, now the computer gets excited but in the old days, we didn't have them) so will the outboard. The net result may be slightly poorer fuel mileage--internal combustion engines do run better hotter (to a degree) but if you need to worry about that, you shouldn't be boating.
I truly doubt that a Force water pump could deliver enough water to cool the engine to a damaging point. I could be wrong though--Heaven knows--I got married, didn't I?
