I should know this "LOL" It has been a while since I changed the coolant in my 99 SP500,so please CORRECT me if I'm wrong guys.If I can recall drain coolant...remove thermostat hose,fill radiator until coolant comes from thermostat housing,replace hose & tighten clamp,with radiator cap off run engine until thermostat opens and top off as needed,continue to run while watching the the bleed hole inside the radiator just below the filler neck,continue to run until the purge hole has a steady stream of coolant,replace cap...50/50 60/40 mix antifreeze/distilled water or premix.Like I said it has been a while

 

You can drain the radiator,pull one end of the small hose from the w/pump leading to the cylinder to drain coolant from the cylinder,not necessary to remove the thermostat and return hose.Jack up the front of the machine with tires off the ground,add coolant and let the fan cycle on and off about 3 times with the cap off.This should remove any trapped air pockets. Top off the radiator and overflow bottle.Most coolant now is 60/40 I believe.

 

Thanks,any recommend brand of 50/50 antifreeze premix off the shelf?

 

Polaris uses 60/40,but whether you use it or any good brand of 60/40 or 50/50 mix coolant doesn't hurt as most now can be used in cars,cycles,atvs,etc and suitable for aluminum radiators.Or you can go crazy like some of cross country and Motocross guys did and use products like this.Although they did swear by it. About $23 for a 1/2 gallon! http://www.engineice.com/