overheating problem, help me wire the fan switch

[bobafett]

OK, first off, let me explain my problem, so that i can be sure i am trying to fix the problem the right way:

my rad fans never seem to want to turn on, but i think its an intermitant problem. however, when i am sitting in traffic and not moving, after a min or two, the temp gauge rises to like 3/4 hot. i dont know if this temp is dangerous or not, but when i see that i usually freak out and crank the heat on until i get rolling again.

my dad had the car before i did, and he claimed the fans came on sometimes, but not always. well i dont really know how to tell, but i cant remember them ever coming on. how can i determine what could be fucking me up? (could it be a sensor, or a switch, or the fan itself, or just a faulty gauge reading?)

ANYWAY, i am asssuming that the temp is rising when i sit idle because the rad fans are not coming on when they need to. since when i am moving the temp drops to a nice cool level. :)

would the simplest solution be to "hardwire" a switch in my dash that manually controls the fans power? i would like it to be a momentary push button switch, with a red/green dual colored LED to show whats going on with fan power. though maybe seperate leds would look better, and use a simple toggle switch.

what suggestions do you guys have for fixing this problem, and do you think the fan switch idea is OK? and dont worry about me absent mindely forgetting to use the switch, i live for shit like that!

[Chrome_thangs]

I had the same problem a while back. Have you checked the sensor in the bottom of the radiator? The one that switches on the cooling fan. I replaced mine and problem solved. It would probably be easier in the long run.

[offthahook]

Sounds kinda like overkill to do your switch idea. My fan bearings went out on the main fan and I just got a new aftermarket one for $40. That's probably NOT your problem, but it might be worth it to replace it if you do replace the thermoswitch. I'd also get a new thermostat, flush and fill it, and check your hoses. If it's none of those (all failry cheap), then it may be a lil more serious. Then, you could do the switch thing, but you are smart not to hard wire cuz running the fans all the time will wear them out. Let us know.

[Jareds 89 LX-i]

Mine used to do that too...it would go 3/4 the way up before the fans would come on. I replaced the sensor in the bottom of the radiator and it didn't do anything. Then I took the 3 sensors out of the thermostat housing and cleaned them off real good, and they work flawlessly. They kick on, off, on, off, on, etc, after idleing a few minutes with the gauge still at normal temp. I can now sit and idle for as long as I want and the temp doesn't budge 1 bit.

Hey offthehook, did those fans not work? I was sure they had worked when I took them out....hmm, maybe they sat too long or something.

[offthahook]

Originally posted by Jareds 89 LX-i
Mine used to do that too...it would go 3/4 the way up before the fans would come on. I replaced the sensor in the bottom of the radiator and it didn't do anything. Then I took the 3 sensors out of the thermostat housing and cleaned them off real good, and they work flawlessly. They kick on, off, on, off, on, etc, after idleing a few minutes with the gauge still at normal temp. I can now sit and idle for as long as I want and the temp doesn't budge 1 bit.

Hey offthehook, did those fans not work? I was sure they had worked when I took them out....hmm, maybe they sat too long or something.

I'm sure they worked and that was our backup plan. My friend runs a Carquest and I told her I'd give her fan ONE try. If it fails, the one you sent is goin in. I still have it cuz the aftermarket fan looked kinda cheap. Your fan/motors owned. I cleaned them up some more, even though they were hella clean. So far, the new motor is working... :)

[bobafett]

ok well it sounds like i should replace the sensor at the bottom of the radiator for starters, and then clean up the thermostat housing...

i have never tried projects like this before, so where do i find the parts on the car, how long should it take to do this, and how much will the sensor cost to replace?

(btw, i am not sure if my fans will kick on at 3/4, since i never want to wait that long, i will just turn on the heat, or shut off the car!)

[88' Accord Ltd]

I was just messing around with my fans last night cause they wouldnt turn on and my engine would heat up at an idle then cool when id drive. but i checked the wires going to the fan i replaced the thermostat because the temps were getting high and on my dads car (88 accord too) his fan would never come on and his temp gauge never went over the half way point even at an idle. But i replaced that and i also replaced a relay in the fuse box under the hood for the fans. Who knows ur relay might be messed up too. Oh and my fans do turn on now like they are supposed to.

[shepherd79]

i would say it is your fan switch. it is located on the bottom of the radiator near lower radiator hose.
another thing your termostat may be stuck on closed. so i would recomend changing that too. it only takes a few minutes. take the two balts out, remove the thermostat housing, take the thermostat out putt a new one with a new rubber gasket around it. putt the balts back on and you done.
ohh yeah, don't forget to add coolant after that.