I recently purchased a 2004 rhino. Unloaded it and after first 10 minutes of riding it started overheating. I washed radiator didn't help, removed radiator had cleaned at radiator shop still did not help with overheating. Next had the head gasket replaced but it still overheats. Also pulled water pump it has no issues. The fan was coming on when it should have but still overheating. Also installed new 12" fan on toggle switch so it can run all the time. Have purged coolant line numerous times. Need some advice. I live in the south so normal temp should be around 200 but radiator constantly boils over.
A few things . Is there any movement of fluids when you remove the rad cap and the engine running?
Is there any coolant in the overflow bottle?
Are you running an antifreeze water mixture or straight water? Water by itself will boil quicker.
good luck
You have 2 plugs to help purge the system. They are at the 1)Waterpump and 2) one by the head.
Note: Try jacking up the front end with your radiator cap removed and purge the system.
Also, Have you checked your radiator cap? A bad cap will cause it to puke out the overflow tank.
I would say your waterpump is ok due to your fan is coming on, due to the sensor is at the radiator. The radiator will typically be cool to the touch if you have a bad pump.
Also, it does not have a thermostat if it is a 660.
And, are you certain it is not a bad head gasket? The reason I say this is I replaced one and still had problems, so I had to put on another one.
If the head gasket is bad, it can show some of the symptoms: 1) pressure in the system, resulting in coolant flowing out of the radiator (with the cap off) and 2) possibly white smoke, 3) water in the oil
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