[good to go]

I have an 06 Yamaha Rhino with a stock engine. I took it for a spin around our short block and when I parked it in the driveway, I noticed the radiator fan was running. Is it normal for the fan to come on after such a short run or do I have an overheating problem? Where should I start to try and figure out what is going on?

 

[canucklehead]

It's better to have in on soon, than on late!

You might want to remove your rad and give it a good cleaning. You'd be AMAZED at the crap that comes out, even when it looks clean.

Also - invest $50 in a shroud (TCP or whatever) that will help that crappy stock fan pull some more air through. The cooling design isnt' the greatest. A SPAL fan and TCP shroud will help a bunch. Also - install a switch to override the fan so it comes on whenever you want...
Also - install a temp gauge so you're SURE everything is kosher... i hate relying on idiot lights!

 

[good to go]

I agree that it is better to come on sooner than later. I'm thinking I may have another issue somewhere else within the cooling system that is causing it to come on so soon.

 

[dbestduner]

get s heat gun and see what the rad temp is when it comes on, should be 175*-185*

 

[WildEarp]

if its coming on early, first thing i would check would be radiator clogged with dirt/mud. Usually have to remove it to thoroughly clean it (flush from backside with low pressure hose), and then I would be sure to completely burb the cooling system of all water. Which usually consists of jacking the front of the rhino up as high as you can and running it in N with the radiator cap off, adding coolant as it goes down, until its fully warmed up. There is also a bleed bolt on the thermostat housing on the motor that you can use to get a little air out too.

Hopefully its something simple, and not a head gasket issue.

 

[honda450sfm]

If you take your fan out , you'd be surprised at all the crud behind there!

 

[WildEarp]

Also, make sure your not running a big front skid plate. They really block air to the radiator. I personally wouldn't run a skid plate unless you have an upgraded cooling system.