Hey guys,

I am new to ATVConnection but it looks like you all have a pretty great site. I am actually a Raptor rider but I am helping my Father in law out with his 1994 Honda 300 4x4. We bought this bike used and don't have any history on it. It does look like the motor has been gone through (I can see the edges of the gaskets) but it seems to run very strong. I have noticed that the temperature light likes to come on when we are riding but the fan does not come on. This happens even if we are just doing light riding in cool weather. I have jumped the hot wire to make sure that the fan works, and it does, but I have never seen it come on. So, my questions are, why would this bike be overheating and why would the fan not come on? I know that this is kind of an open ended question, but I will take any information that you can provide.

Thanks,

Jason

 

The fan that is on that machine did not come standard. I put a fan on my
1998 300 4x4 but it is not the model that Honda offers. I plug the fan
in when I am going slow pulling a bushhog because there is hardly no air
flow over the fins. My 300 runs hot in the dead of summer but no light
yet.

Even when I didn't have the fan my light has never come on except for
when you turn the key on right at first. If the light comes on, the fan
should be on.

How long are you riding slow before it comes on? How long does it take
for the light to go out after the machine is shut off?

Are your fins are clean, fresh oil,new oil filter, air filter clean?
This sounds like something electrical.

 

I am not sure if my fan is a Honda part or not. You know, it doesn't take very long at all for the light to come on and it does it very unpredictably. Sometimes I will get on it and it will come on within 5 minutes of running around, other times it will take a long time to come on. I was out with it about a month ago doing some real riding and it came on maybe once the whole time that we were riding. I agree that it definately sounds electrical. So, I guess my biggest question is what controls the temperature light and the fan? I did pull the fenders and look at one point but all I found was a black potted electrical assembly that a bunch of stuff plugged into.

I will take your advice and change the oil, oil filter and air filter. This probably should be done anyway.

So, any suggestions on diagnosing the electrical?

 

I wish I could help on the electrical part. Have you checked the fuse? I have only seen one of these fans and it was on a used model at the dealer and that is how I found out honda even offered a fan for the 300 series. I checked into it years ago and if I remember correctly it was over 200 dollars for the fan.
I am not even sure where the sensor is for the fan.

I just thought for $200 dollars I could rig something up myself. So now I just plug mine into the power point on the right handlebar when I want it on.

Maybe someone else has some insight into this.

 

Yeah, I checked the only fuses that I could find and they all seem to be ok. So, what does the temperature light on the dash measure? Oil temp? Thanks for the help RAPTORYFM660r.

Can anyone else help out here??

 

So, does anyone else here run the auxillary fan on their 300? I am curious what kind of wiring you did to make it run at a given temp.

Thanks

 

ijeep,

mabe you should try running a switch for the fan,
then it can be turned on anytime..........

juct a quick solution........

 

Yeah, I thought about doing the switch. As I mentioned in the original post, the bike also has a tendency to flash the temp light at me also and since this bike is for my Father in law (who is older) I want to try and get everything working properly so that he doesn't have to worry about anything.

 

I guess there are 2 thermostat switches on the bike. 1 factory one to turn on the light at high temp, and 1 aftermarket to activate the fan when temp is getting close to what the light is set to. Trace the wiring for the fan to see what is what. If the fan's sensor is defective replace it, maybe both of them if the light is coming on when engine is not hot. If the engine is overheating, have carb checked, I think a lean condition may cause engine to run hotter.

 

I guess there are 2 thermostat switches on the bike. 1 factory one to turn on the light at high temp, and 1 aftermarket to activate the fan when temp is getting close to what the light is set to.

-So are you saying that for sure there are 2 thermostat switches or you think that there might be?

Trace the wiring for the fan to see what is what.

-I did this and the fand wiring seemed to lead to a black potted box on the front of the bike. The box had a bunch of wires hooked to it.

If the fan's sensor is defective replace it, maybe both of them if the light is coming on when engine is not hot. If the engine is overheating, have carb checked, I think a lean condition may cause engine to run hotter.

-How can I tell if the engine is actually running hot or not?