cold water and no T Stat

I have 2 Polaris 1200s now and neither has a thermostat. This bothers me for cold water riding. How cold is too cold in this circumstance?

Any thing less then at least 100 F at WOT out of the head could result in serious damage, specially if bore to piston clearance is tight. I like to see 120 F on avery engine. Do not forget to set up fuel delivery according to RAD. PS. Do not fall for the popular but terribly misleading statements, which say that if you worm up your engine for long period of time you will be safe. Nothing can be farther from the truth. At WOT jet pump delivers high pressure, water flow true engine block is high at WOT, if this is not taken seriously, must machines will become statistic, period

I wonder why Polaris stopped using the T-stat in the new models? George can better answer the cold water restrictor jet in the cooling line trick for cold water riding. From what I have learned, you need to find the corect operating temperature of the engine by using restrictor jets in the water by-pass going out from the pipe. In your case, you might be able to put a thermostsat into the place where it normally goes.

I agree with you on the possibility of just install a t-stat. I was just curious if anyone really has had a problem. Of course, I don't think anyone else on here was nosy enough to even know they don't have one, so I may be the guinea pig this time.

Thermostat is not very good idea on PWC engine, heat exchange unit works better. Seizure can happen due to slow reaction time of thermostat when outside water temperature drop below 50 F. Sudden rush of cold water in to the engine block cools part of cylinder and head very fast, while other portion remains very hot. By the time thermostat closes it is to late, not to mention possibility ow plugging it up and failure to close is high. It is good idea to preheat water be for it enters cylinder block. I set up my machines very carefully. Each head should flow water with in 5 degree from each other. If that is not done avery thing else will be out of balance, carburetion will become pain to adjust. When water drops below 50 degree I use 'T' valve which bypasses water pressure be for it enters in to the engine. I use home made restrictors all over the place, sizes very from 1/32 ' to 1/4 ' ID. This is serious business any mistake in engine cooling and even momentary lean run will cost you big $$$$$$$$$$$$. Make sure that water out the head reads at least 100 F at WOT 120 is ideal. Do not venture alone when it's really cold. During winter mouths I use my in closed trailer which is heated and I do not travel far from it. At 16 degree air and 36 degree water, life expectancy is very short. I use my snowmobile outfit when testing parts or challenged to race.