I have a blade on my 99 400 4x4 which I use to plow snow in the winter time, it works great. Today I thought I would try and see how well it workes with dirt. I just went to one of our fields which was freshly plowed and started pushing some dirt. It didn't seem to working the quad really hard and I plowed for a couple of minutes, then I looked down and the exhause pipe coming out of the motor was a glowing a bright cherry red. I was really surprised, because the motor didn't feel that hot. Has anyone else experencied this?
The fan for the rad also did not turn on at the time. I checked the fuse and it was fine. I was wondering where exactly the thermostat is located which switches on the fan, I would like to check it.
Has anyone tried to put a water temp guage on? If so I would be interested in any details.

Thanks in advance.

 

I have a 2000 400 4x4 and the fan runs all the time, maybe there is a problem with your fan. Some of the people in the group have had fuses blow after putting the fan underwater, I know you said you checked the fuse but you should get out a multi meter and confirm power at the fan.

Regards Jim

 

I have a 99 500 and about a month ago I was riding at night, and looked down to see the same thing. Pipe coming out of the motor glowing cherry red! I freaked and took it back to the garage and parked it wondering what was up. Then later I made the mistake of taking off that bolt to clean the spark arestor. Big damn deal! I had to use a propane torch and vice grips to get it off, and I didn't notice much of anything coming out of the muffler when I went to blow it out. The replacement plug cost $4.25 too. For a single little brass bolt. I sanded out the loc-tite out of the grooves, replaced the plug, and I will never take that thing out again. I don't know what caused the pipe to get so red, but I'd like to know.

 

If you put some high temp anti-sieze on it, you won't have a problem getting it out, I had heard some earlier complaints about that #$%^ plug and took mine out right away and anti-siezed it, had it out a couple weeks ago, came out just fine. Maybe my luck finally turned around.LOL

 

This must be normal cause my cat does it after about 15 min of trail riding.

 

My 454 gets that hot to I put a Highlifter heat fighter kit on it and it helped . The switch on the 99 400 is located on the lower left hand side of the radiator , The switch on my 454 went bad but the temp light would come on with no fan ,the switch cost $45 so I wired a switch in it , Then the fan motor went bad , I think that was over $200

 

I think that the problem may be solved by purchacing a Yamaha!

 

this topic was discussed before and i think its common with stainless exhaust systems.i dont think the bend over the starter helps.

 

As far as I know the cooling fans are activated by a thermostat for the models prior to 2000. For 2000 the fan is powered constantly. I've got a 2000 500 auto and haven't noticed my exhaust pipe getting glowing hot. I've riden quite a bit at night although it has mostly been during colder evenings, riding on snow covered trails.