I have a 2005 polaris spostmans efi 700, its overheating and driving me insane!! It has 42 hours on the bike and around 200 miles.
Ill start from the beginning. Ive relocated the radiator, snorkeled it, lifted etc. Ive had zero problems with it.
i ended up getting a hole in my oem radiator. I replaced it.
its been overheating since. Heres what ive done.
i filled the new radiatorand burped it, still over heating. Fan coming on before the hot light. I can drive around for 10, 20 mins and drives great. I come to a idle and it flashes hot. At this point its pushing fluid out of my reservoir. So i removed the thermostat(which passed the pot test) and even without a thermostat it still over heats pushing it out of the reservoir. I checked the water pump when i first started having this prob and it looks fine, and spun when i hit the starter button a few times. Ive burped it and burped it and it just not changing. Even changed the rad. Cap with a replacement from autozone with matched up.
what i did notice today is the bottom hose doesnt seem to have alot of fluid in it. Also when i had someone rev the motor up the bottom hose collapsed.
Any help would be grateful. Im at my wits end.
do i have a air lock problem? If so how the world do i get it out!?!? Head gasket?

 

assuming the radiator is clean and does not have mud caked in it? it's been awhile I but I remember I think the book says to have the front of the bike raised up with the cap loose to purge the air out and running it for a few minutes. I know it sounds stupid but it's suppose to work.

 

See if you can find an owner's manual. I think you have to actually raise the rear end up to burp any air out of the cooling system. It's been a long time since I owned a Polaris, but my Cat's all require jacking up the rear while filling coolant. BTW, the 400 Sportsman that I owned ran hot , especially the exhaust. I gutted out the muffler, suddenly it ran cooler and stopped melting plastics.

 

Raise the front end a few inches with the radiator cap off and the engine running. When the coolant level drops add more. Repeat until done burping. Add coolant to overflow bottle if needed. ETA: Never mind. With the radiator relocated I don't know if that still applies or not.

"what i did notice today is the bottom hose doesnt seem to have alot of fluid in it. Also when i had someone rev the motor up the bottom hose collapsed."
Maybe the new radiator has something in it blocking the flow of fluid.

 

Ive done the raising up and i had no luck, i took the bottom hose off tonight and it had a good flow coming out of it. I change that soft hose out with a new one and im going to try the burping again. Tomorrow afternmon hopefully.
my exhaust is already modified and breathing better.

 

I have a 04 700 that I did a ton or work on to resolve overheating. The gauge/spedo would flash “Hot” after about 20-30min of normal usage. It has done this for years. I finally decided to hook up a manual water gauge in place of the sender on the head next to the thermostat. That sensor is a normally open switch that closes when the water temp gets to 230 degrees F. The manual gauge confirmed the sensor is working. I have a brand new radiator, new radiator fan switch, new thermostat, new water pump and new radiator cap and still after about 30min it eventually gets to 230+F. Note: the fan does kicks in and out normally. I notice the radiator doesn’t distribute the hot water evenly for cooling as the engine warms up. I also noticed the fan switch is on the opposite side of where the two lines come in. The two lines are on the LH side and the fan switch is on the bottom RH side so it sees the hot water dead last…

(Already)Long story short there is a ¼” coolant drainage line from the head (right next to the thermostat) that drains back into the filler neck. This line allows for some coolant to be moving/flowing while the engine thermostat is shut so the water pump isn’t deadheading. On my 04 700 there is a short line that goes from the top RH corner of the radiator to the filler neck. I simply ran a new, longer ¼” line from the head directly to the top RH corner of the radiator so the fan switch has instantly hot water and now it runs exactly 180-190 F all day no matter what.

I’m planning on taking some pictures and posting it on youtube or on this website soon.