Yamaha Rhino Forum banner


3753 Views 8 Replies 7 Participants Last post by  SouthBay4Life
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.
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Have you tried to run it witout the thermostat?Or checked the T-Stat?Just a thought.And you are purging at the cylinder head?
I am purging on the cylinder head and their is not a thernostat. I been trying locate one that I maybe could install.
You might want to call or message some of the engine vendors on this site-good luck
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
If I am not mistaken there is also a place to perge it down by the waterpump also
loosing coolant

i have some good info on how to replace mechanical seal on a rhino 700. dealer wanted 400.00 for labor and they offered no info on how to change it.
Here are some thoughts that might help you.

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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Where is the second purge location? The one by the head? Had the same problem recently.
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