have a 1993 TRX300EX that I rebuilt the top end of the motor a little over a year ago, bored 50 over, I also did some custom work in mounting a winch on the front of it. Some of the riding I'm doing is on trails in the woods and its hot humid and even alot of mud in some places, well the point being is that when I'm winching either mine out or another ATV out and its sitting still at idle during this time it seems to over heat and even after a long period of time will die on its own, will restart with little to no problem, so I'm kinda looking at putting a cooling fan on it with a manual on/off switch and run it when winching and running when its really hot, just to move air around the motor when its not moving since it is an air cooled motor not designed for idle sitting or obviously really doing the type of riding I'm doing, just wondering if any one has ever done this and how well it has worked?

 

How hot is it actually getting?

These engines are tougher than you might think. A lot of quads and in earlier days Big Red's get idled along for hours spraying weeds and doing other farm work.

Still, a fan couldn't hurt. Even just a cheap computer cooling fan might do what you want.

 

For what you are doing with it, I would say that a cooling fan is justly needed. You have plenty of room on that model to mount one. You could use smaller type made for an automobile or buy an entire cooling fan with bracket off ebay that fits a Foreman and modifie it to fit the 3003EX frame. The 300EX has enough juice to power it.

 

Thats what I was thinking too, found a 7.5" that moves roughly 440 CF/M. I've read and got replys on a couple other forums that I'm on about guys putting oil coolers on theirs as well, anybody know anything about this? Is it worth it to me to go that route or is 440 CF/M enough?

 

Running with oil below optimal temp can be as bad as overheating the engine.

I would suggest installing your fan, and measuring oil temperature.

That would be the only way to really know where you are at.

 

You should run an external oil cooler.

I had one on my 1994 300EX, made by Jagg, and it definitely allowed the engine to run cooler.

Wiring up a small fan to draw air through the cooler and then across the engine would be optimal