[Dillegm]

Hi there,

So I haven't ridden my 400s in months, but I just rode it recently and noticed it nearly overheated very easily and after investigation it turns out my fan no longer operates.
I checked the fuse and it's fine, but I changed it just in case. Nothing.
The relay "looks" ok but I dont know how to test it.
No wiring seems to be interrupted either.

Anyone have any suggestions for me before I tear into this head first? I need to get the plow ready for snowfall soon.

[NMKawierider]

CFM's fan switch AKA thermoswitch is prone to fail on all models. It's on the radiator. There is a connector near it. Unplug that connector and jumper the two conntacts inside the harness-side. Then turn the key on. If the fan runs, replace the thermoswitch.

[Dillegm]

CFM's fan switch AKA thermoswitch is prone to fail on all models. It's on the radiator. There is a connector near it. Unplug that connector and jumper the two conntacts inside the harness-side. Then turn the key on. If the fan runs, replace the thermoswitch.

Thanks man, I will. I read that using a Toyota or Honda thermoswitch is recommended somewhere, but I'll be damned if I can find it again. Are these easily found online?

[NMKawierider]

CFM's fan switch AKA thermoswitch is prone to fail on all models. It's on the radiator. There is a connector near it. Unplug that connector and jumper the two conntacts inside the harness-side. Then turn the key on. If the fan runs, replace the thermoswitch.

Thanks man, I will. I read that using a Toyota or Honda thermoswitch is recommended somewhere, but I'll be damned if I can find it again. Are these easily found online?

I always thought "when" mine fails I would just get someone else's switch like a Polaris and just wire it in as the connectors don't seem to ever match...and some of theirs have pigtails. But I get several different readings as to the thread size CFM uses so that thought just kinda stalled. The other thing is they are being made by someone else now and are supposed to be better so...maybe just get a new CFM one. If it fails again..look to another source.

[farmerklaus]

My Thermoswitch was also broken.

I noticed it, because the engine temperature runs into very high. ( I was on the daily trip to work)

But i was not a big problem to change it, i ordered a new one, dismounted the bad one, hold the

finger on the hole of the cooler and mounted the new one. Ready in 15 minutes. But this Thermo-

Switch costs 30€, not really cheap

[Dillegm]

So I jumped the harness connector to the thermoswitch and the fan runs constantly with the ignition on, so that was indeed the issue.
I've ordered a new one and for now just left the jumper connected so I can pull my swisher mower for fall cleanup.

Thanks very much

[NMKawierider]

Good. An easy fix.

[Dillegm]

I finally got the replacement sensor in this week and installed it. Works great and was easy to install.
$18.99 US on Ebay if anyone is curious. I've since found them cheaper on Amazon as well. Apparently it's the same sensor the 800 takes.

[Skogsvarelse]

The new sensor should be better because they canged something because the old ones broke to often so the original switch should do the work so long you get the new modell of the switch (Loocks neraly the same one of them should hava a mark on the side of the switch)

[Dillegm]

The one I got crapped out almost immediately so I assume it's the old style.

My other plowing thread explains what happened. Apparently I posted about this in the wrong thread originally, oops.

The machine overheated again, but this time I got a small amount of steam, and an audible sizzling noise like it was dripping on the exhaust or head. Not sure if it's a leak or one of the overflow lines.
I need time to disassemble some plastics to get a better look.

Do you have a source for new style thermoswitches?

[doug80638]

Pressure test your cooling system before you get too deep into it. 

That should make finding any failed gaskets or seals easier.