fan problems

[bigz-71]

i am having trouble with my fan. it will not come on. we by passed the tempature sensor. we pluged it into a 12 volt battary and the fan will come on that way. the motor on the fan is still good but why will it not come on. they say it takes the bike to be 202 degrees hot before the fan will work but it should work if i by pass it right? if anyone out there can help me please do. i need to get it fixed.
thanks
Jeremy

[Big Slick]

My fan has never turned on since day 1. I don't think it's been warm enough outside yet.

I think it's pretty common.

[Varmit57]

I have had my 450R since Feb 04 and have only noticed the fan running maybe a dozen times.

Most of the time that is when I finish a MX Race and shut it down near the finish line. If I idle back to the pits before I shut the quad down the fan usally has already shut off.

[bigz-71]

i know my bike was hot enough, i was spitting out coolant. i could hear the antifreeze bubble when i turn it off. i also by passed the tempature sensor so the fan should automatically come on then. well i know it has been a problem for some others too. i just wondering if anyone know how i can fix my problem.
thanks
Jeremy

[brandonpeake]

i have only had mine come on one time, if i were you i would just wire a switch to it and man turn it on when i needed it

[PaperChazerz]

Brandonpeake.... Thats what i did. Bigs-71 i had the same problem and i fixed it by putting a swtich on it. Putting a switch is very easy and to me kinda fun i duno why. My bike never over heated but now when im done riding and before i shut the bike off and when coming home i turn the fan on. Its all good now.
You can buy a switch at lowes, pepboys, hardware store, paces like that.
SEMA

[bigz-71]

thanks for the help.

[Shawn H]

I had the same problem and it can only be a few things if you jumped it correctly!!

You ground the wire at the coolant sender and it should work no matter what the temp is!! If it does not work your fan could be bad? try powering it up

The little black box is bad(swap with known good one) in the front of quad or which was my problem the wires were shorted out at the rectifier.The book does not tell you the fan goes thru there unless you look at the wiring diagram. i had to replace the rectifier and the harness.

During a race a stick had wedged in between the electrical plug and the rectifier causing it to unplug a little and have a bad connection it all burnt up.

parts were cheap 110 for new rectifier and harness

Hope this helps
Shawn

[BSTURDIVANT]

Problems usually show up after removing the ignnition switch!
Either leave switch on and wire tie under hood or hook the wires together so voltage can get to fan.

[Shawn H]

This is true but I have mine soldered together.
He does not mention if he has the ignition removed?

[bigz-71]

how much is the black box? i know my ignition is still good. its not solder but it twisted together. i had a volt meter to all of it and its getting 10.4 volts at the ignition and 8 volts at the plug for the fan (the blue one under the hood). i hooked a car battary to the fan and the fan did come on, so the motor is still good on the fan. i did ground the tempature sensor out and the fan did not come on. i am thinking it could be that black box but i dont want to have to buy a new one if i dont have too (unless its cheap then i will do it). i called the shop that i deal with and they told me to check the hot start cable, i was like what does that have to do with it.

well my other question concering the fan is, how did yall wire up a switch? what powered the fan? does it ran all the time when the bike is on if the switch is on and does not run at all when the switch is off.

well i appreciate everyones comments. Snowgasm you helped a lot. how much did that black box cost you?
thanks
Jeremy

[Shawn H]

Jeremy,
You did check all the connections everywhere right? Dont bother with a switch thats just problems what if ya broke a wire and ya thought it was working and it wasnt?Fix it right

I have a spare Good Ignition box I can send ya for you to test to see if it works. The ignition has nothing to do with the fan if you have it all hooked up, If you removed the ign then you have to splice 2 of the wires together to complete the circuit for the fan>

P.m me your address I'll ship ya the little black box> Reason I have a extra one is I bought a complete New harness and black box for 40bucks from a guy who swapped over to the CRF wiring harness

Oh BTW Tell your dealer I said they are dumb azzes lmao

Hot start they are retarded!!!

[bigz-71]

snowgasm,
if the ignition box has nothing to do with the fan then why send me one to try. i do not have a key on my bike anymore. i have the two wires twisted together so that it acts like the key is always on. i did have trouble in teh past because i removed the key but did not twist those wires together. could i have lost voltage somewhere so that the fan is not getting a full 12 volts? i grounded out the tempature sensor so the fan should automatically come on. i need some advice on what i should try or do next
thanks
Jeremy

[Shawn H]

No the ign box does have something to do with it, I meant the ignition switch> Your sure the wires ya got twisted are a good connection? Let me know if ya need the box>You need to try a good black box, and check all wiring and connections you could take a meter and check resistance of the wires maybe ya have a short and you are loosing voltage? Dont check for continuity cause even 1 strand of wire out 100 will show some continuity

[bigz-71]

how do i check for resistance on tbe box?
why would the ignition box go bad?
how much is a new ignition box?
at least this problem happened now while its a dead time.
thanks Snowgasm
Jeremy

ps i will let you know about that box but i am going to check those couple of other things before i get you to mail me that box. i guess if i cant get it to wokr i will get you to mail it to me.

[Shawn H]

There is no way to test the box the manual plainly states swap with known good cdi. If you have 8 volts that tells me somewhere you are loosing some voltage thru a bad connection or a short. The cdi box is 263.00:eek2:

This is from the manual pg 16-22
if fan will not start from jumping ect sensor check for open circuit in the following wire. Green wire between fan/ICM(Ignition control module) and the fan motor connectors, and
Green wire of the fan motor

If the wire is OK disconnect the fan motor 2P PLUG ( Blue 1 left side where all the little plugs are on the frame)Start teh engine and measure the voltage between the BLK wire terminal+ and Green wire-

If there is generating voltage replace the fan (You already no the fan is ok cuz you supplied with power)

If there is no voltage check for a open circuit in the BLK wire between the fan motor and the IGN switch connectorsIf the BLK wire is ok replace the ICM?CDI

Good luck
Shawn

[bigz-71]

why are the cdi boxes so damn expensive? the one for the 400ex was like a 100 bucks. its crazy its so damn expensive for the 450r.

[Martin Blair]

big gun and other aftermarket are down arround 100, look arround you'll find em

[kgbg]

The Procom boxes are bad news. I do believe any box avail for under $400 is Procom. You should ask, and if it is, DO NOT BUY IT!



Fan Problems: Get rid of the fan, solved!

[jacksongncc450]

I was thinkin about taking my fan off. I noticed at a race that Jathan Seale had his off so i guess it doesnt overheat. Has anyone else taken there fan off? It seems like in a 2 hour race it would overheat without it.Let me know.

[kgbg]

Think about this:
The dirt bike, has more compression, hotter CDI, ect. and they have no fan.
I heard the radiator is larger on the quad (not positive, just what I heard) too.
A radiator works by allowing air to flow through it, and the fan is a large blockage, not allowing air to flow through the radiator.
Dirt bike riders do not sit and idle. Quad riders do. Just don't sit and idle, and in my opinion it would be OK.
This is just my opinion, but I might be able to call it an educated guess.......:cool:

[Jersey450R]

Originally posted by kgbg
, but I might be able to call it an educated guess.......:cool:
You mean a hypothesis :p

[kgbg]

I can't remember, does a hypothesis mean you have tested it yet?
I have not yet. But my fan is no longer hooked up!

[450rRIPPER]

hypothesis is just the idea.

[swoulter]

i know your problem what you need to do is take you quad and sell it and get a yfz450 because your honda was thrown together to try an compete with it. lol jk well not really but yeah

just ignore this i am bored

[450Rkid]

I read in dirt wheels that a guys fan wasent working and instead of buying a honda one he ordered one from summit racing call them up and they will deffinatly help you out

[Shawn H]

I can tell ya 7 hrs into the 12hrs of america by shock resevoir line broke off the sender wire and made my fan not come on. For 5 hrs every 2 laps we came in and added coolant. It was fine in the wide open places but when it got tight and technical it would start to boil over! My fan is staying on I also got a Fluidyne radiator ordered so I have plenty of cooling>

BTW it was pretty chilly out to in the 40's

[team_450_88]

I dont have a fan but I run LP( liquid performance) racing coolant, which is some good stuff and also a inline-cooler

[Jersey450R]

do them inline coolers really help out?

[Shawn H]

Originally posted by team_450_88
I dont have a fan but I run LP( liquid performance) racing coolant, which is some good stuff and also a inline-cooler

And you race MX right? 20 Minute motos maybe? There is a diffrence between 20 minutes and 2hrs.

Also you are always moving at a faster pace, When its tight in the woods you can be at a crawl or standstill with bottlenecks.

I wont run them inline coolers they can restrict flow, I remove my thermostata tho and leave it out>

[burnerboy8]

im in the same boat