So HUTC1510, if you knew you were not going to put the fan back in or that Honda never had fans before so they must not be needed, why did you post your original question about the fan. Personally, I think you are crazy not to have the fan in place! The last thing you want to do is have the oil overheat and cook the low end, but since you seem to know more than anyone, good luck with the rebuild!

 

Does anyone know where I can purchase a oil temperature sensor for a 2003 Honda rancher 4x4 350? my fan doesn't come on and I checked it out its the sensor I need. Thanks in advance James.

 

My 1989 350 Yamaha Big Bear had a oil cooler but no fan from the show room and is still running.
Even without a fan the oil cooler still does its job by redirecting the oil through the rad to give the oil a cool time period before re entering the crank case. The fan is just a assist option not a necessity like on a Liquid cooled rad.

Some air cooled 350 class ATVs don't even have a oil cooler period, like the Honda 300 Fourtrax. and you see them everywhere ,yet not over heating. Another one is the 350 Yamaha Worrior never had a oil cooler stock.

If the oil cooler fan on my 350 Grizzly quit working ,unless it was a simple easy fix I would not put much effort into fixing it since its the exact same motor as my Big Bear had without a fan and it had a smaller oil cooler rad.

 

I think the only time my fan has ever come on on my Rancher is if I've been riding and park it and it sits and idles for a few minutes. When you're moving, you're getting airflow and the fan is not needed. When sitting, its going to eventually need a fan to keep the engine cool. It doesn't happen very much but I wouldn't remove the fan. Its meant to be there, Honda designed it that way.

 

Any Honda dealer can supply a new sender unit for the fan. Unless you are inclined to leave the machine ticking over for long periods (why?) Or do work like harrowing, which is low speed and hard pulling, the fan probably won't come on, but it is there as a safety device to stop overheating.

 

It came with it and I want it back like it should be period. Thanks James

 

I think even when just parked idling just the fact that the oil takes a long external rout through the lines and oil rad before re-entering the motor it helps cool the motor oil, fan or no fan.

 

my '13 rancher's fan cycles like it should. after extended distances and then stopping, the airflow across the rad stops, temps climb and then the fan kicks on and man does it make a difference. i can feel hot air pouring out around my feet and legs. it runs a few minutes then shuts off. if you dont start moving, it will kick back on.

 

mine comes on regularly. it's a water cooled engine surrounded by allot of plastic that traps heat- it was designed to use the fan in conjunction with the radiator.

 

The fan on a ligiud cooled rad is a "necessity" without it your walking because the water will quickly steam and boil over.
The fan on a oil cooler is a "assist" feature to help the oil cooler.
Even if a air/oil cooled motor had no fan it will run all day long.
Some air cooled motors do not even have a oil cooler let alone fan like the 350 Yamaha warriors even though it has the same 348 motor as the Big Bear and Grizzly which do have a oil cooler.

Sometimes simple is better.