cooling fans

[labeledsk8r]

allright, just a quick noob question, i just got done takeing my a/c compressor out and all that good stuff, and i took out the small fan on the right (faceing engine bay) the one in front of the a/c compressor and the power steering, i was planing on rewireing it back to a switch later so i can have it on when i need it on myself, but later that day i was helping a buddy on his 88 lx-i and the automatic fan came on and i noticed it was the smaller fan spinning not the larger fan. so the question is, wich fan is controled by the a/c and wich is controled by the thermostat timer, thanks

[DBMaster]

Both fans come on as required when the engine is running. That will happen when you are not moving and the A/C compressor kicks on, or when the temperature sensor at the bottom of the radiator senses a temperature limit.

The small fan comes on by itself when the thermo switch (located in the thermostat housing next to the ECU temperature sensor) senses a temperature limit with the engine shut off. The ECU runs the small fan for 15 minutes in that situation.

I have noticed on my car that the motor for the smaller fan is much less durable than the larger one. I had to solder new leads to my motor several years ago when it developed a short and I had to replace the motor itself about six months ago.

[labeledsk8r]

ok so the idea of puting the small fan back on as a manuel switch is a bad idea, it came out with the a/c compressor, i dont think i have ever seen either fan work, might be something in sensors i guess, thanks

[A18A]

ok so the idea of puting the small fan back on as a manuel switch is a bad idea, it came out with the a/c compressor, i dont think i have ever seen either fan work, might be something in sensors i guess, thanks
how about wiring both fans together?

[labeledsk8r]

i figured if this fan was only for the a/c then i would do the manuel switch so i could have a fan going even with the key out of the car, for one reason or another

[A18A]

i figured if this fan was only for the a/c then i would do the manuel switch so i could have a fan going even with the key out of the car, for one reason or another
well you can do both i supose, IMHO having the fans running with the car off is just asking for a flat battery (asuming one time you mightr forget)

[labeledsk8r]

mostly i would want it for going down to the track or anytime have been running the car for a while, i dont fully trust the cars sensors so i was debateing on it, plus this is florida so i gotta try to keep it cool

[crazykamper]

yeah, if i were you, try to somehow wire it up so that it automatically goes on, but also have a switch wired to it... just an idea (dont know how that would wire up....)

[A18A]

yeah, if i were you, try to somehow wire it up so that it automatically goes on, but also have a switch wired to it... just an idea (dont know how that would wire up....)
would be pretty simple really, wire it paralel to the other fan, and put a switch between positive of battery and + of fan :D then u can turn it on whenever

or how about wire it the sensor and fan straight 2 the battery so wen the key is out, it will just run untill its cool. like a 4g, the fan runs without the key for 15 mins i think (or till temp drops)

[Accordaone]

For some reason, the 3g fuel injected will run for up to 15 minutes with the ignition off, depending on the coolant temperature, but not the carbureted models. There is a timer under the driver's seat, along with a thermoswitch on the thermostat housing and the bottom of the radiator. The small fan is the a/c fan, even though it is the one that runs after the ignition is off. Don't know why the carbed models don't run after turning off the ignition.

[labeledsk8r]

allright gotcha, so it it be wise just to make a stand alone switch, or should i just plug it back into its normal plug and just leave it alone, and do i even need to put it back on, im allready loveing the space, and my car never went apove normal temp today?

[frantik]

my LX's fans were shot and most of the time i was able to stay at normal temps, but if i had to idle for over 5 mins then the engine would get hot. same thing would happen when i was driving in SF waiting at lots of lights without a lot of driving in between.

So be careful.. you might be able to drive without overheating for a while but if it gets too hot even one time you're risking a lot of damage. mine ended up messing up the head gasket and it wouldnt pass smog any more :\

[labeledsk8r]

well the big fan is still pluged in and i watched it turn on and run (only for about 2 minutes) and shut back off, i truely think my thermostat is screwd up but i dont know.

[A20A1]

I hooked one fan to (ON WITH IGNITION) wire and the other fan to a switch.

Both fans are the larger fan though. I wanted all the cooling I could get.
http://www.3geez.com/forum/attachment.php?attachmentid=3099

[labeledsk8r]

does the larger fan hook up easy to the smaller mounts, haveing 2 larger fans is a good idea for cooling

[Oldblueaccord]

I pull the fuse on the AC (10 amp) and then run the AC on button and the fan on low. The ac light lights but the compressor doesnt clutch in and both fans then run. I do it when I go up to 129,the Dragon, and run in the summer.

wp

[POS carb]

Smaller fan = condenser fan.
This cools the A/C refrigerant and should come on any time the a/c is on.

larger fan on the passenger side is the main cooling fan. this should come on with the a/c or as needed by engine temp.

on my LX the damn sensor on the radiator kept going bad so I put a jumper clip (paper clip) in the harness and both fans kick on whenever the key is in the "ON" position

[labeledsk8r]

ok so its fine to leave the smaller fan out since my a/c is gone, also is there a way to test the larger fan sensor? i need to know if i should get a new sensor or not since i hardly see the large fan on

[88Accord-DX]

Description
A coolant recovery system differs from other cooling systems in that an overflow bottle is connected to the radiator overflow hose. Overflow bottle is transparent or translucent to permit checking of coolant level without removing the radiator cap. No adjustments or test is required except keeping vent hole or hose clean & checking pressure relief of the radiator cap.
Operation
As coolant temperature rises & pressure in system exceeds pressure releif of radiator cap, excess coolant flows into overflow bottle. As engine cools & coolant contracts, vacuum is formed in the system. Vacuum draws coolant, stored in overflow bottle, back into radiator. In a properly maintained cooling system, the only coolant looses will be through evaperation.
Thermostatically Controlled Electric Fans

Discription
Electrically-driven fans are actuacted by thermal relay switches. Thermal switches turn fan motor on when neccessary & shut fan motor off when not needed. Air conditioned vehicles are equipped with over-ride switches. These switches turn fan motor on whenever air conditioning system is operating. When system is turned off, fan motor is returned to thermal relay.
Fan motor test
Disconnect fan motor wire connector and connect it with 14 gauge wire to a 12-volt battery. If fan runs, motor is ok. This indicates car battery, thermal switch, radiator fan switch, coolant relay, timer relay, coolant temperature switch, or A/C relay may be defective. If the fan motor doesn't run when connected to a battery, replace the fan motor.
Temperature Switch Test
On all models, the radiator fan timer/temperature switch is located on the top of the motor, near upper radiator hose. Switch should have continuity when coolant temperature is 226 degrees F or more.
On A/C equipped models, the radiator fan temperature switch is located in the lower radiator tank. Switch should have continuity when the temperature is 194 degrees F or more.
Fan Controller/Timer & relays
(This relates to EFI Accords)
A solid-state fan controller/timer, located under the right front seat, uses input from the radiator fan timer/temp. switch to operate fan relay. The fan controller/timer also uses input from the radiator fan temperature switch to operate A/C condensor fan relay. Both relays are located in underhood fuse box. No testing is available from the manufacturer. Do not check resistance of fan controller/timer. Relays can be tested, but need some electrical knowledge on how to test them


ok so its fine to leave the smaller fan out since my a/c is gone, also is there a way to test the larger fan sensor? i need to know if i should get a new sensor or not since i hardly see the large fan on
Yeah man, that temperature sensor on the bottom of the radiator tank is causing your fans not to kick in. I had the same problem.

Here is my problem back a while back.
Well, I got the sensor for $17 and some change. New radiator for $99, lifetime warranty. The temperature sensor takes a 22 mm wrench & came with new O-ring.
http://img.photobucket.com/albums/v488/ddude2uc/radiator.jpg

[labeledsk8r]

ok so that one sensor controles the large fan and the small fan, i still havent put the smaller fan back in lol. it seems to run fine but i might be stupid

[labeledsk8r]

actully the radiator is only a year old give or take a few months, it was just installed just before i bought the car. but not to sure about the sensors

[88Accord-DX]

ok so that one sensor controles the large fan and the small fan, i still havent put the smaller fan back in lol. it seems to run fine but i might be stupid

Yeah, that temp. sensor kicks on both my fans. It might be cause I have my A/C removed though.

[88Accord-DX]

actully the radiator is only a year old give or take a few months, it was just installed just before i bought the car. but not to sure about the sensors

If you have a multimeter, you can remove it & put it boiling water & check its' resistance at 197 degrees. (or whatever my previous post mentioned)

[labeledsk8r]

allright i will try that in the next few days, for some reason it seems to be running cooler then it used to before i removed the a/c (atleast thats what my cars heat gauge says)

[88Accord-DX]

Set your multimeter on ring tone on Ohms. Put the sensor in water that is getting hot. Might need a thermometer. When it gets to 194 degrees, you should get a sound. (beeping noise)

[labeledsk8r]

lol i have a cheap multimeter, so should i just get a spike of power on the ohm setting

[88Accord-DX]

lol i have a cheap multimeter, so should i just get a spike of power on the ohm setting
I would think you should if you set the Ohms readings right. I don't know the resistance of the sensor at this time. Sorry, I use a Fluke multimeter when testing temp. sensors.

[88Accord-DX]

Douple post shouldn't be here if posted within 5 seconds.

[88Accord-DX]

Let me revise this thread, it is not Ohms setting I mean. If you have continuity setting on your meter, that is what you need to set the mulitmeter at. Once the sensor reaches 194 degrees, you will have continuity.

I'm so used to testing other sensors & such using OHM's setting with resistance. :)

[labeledsk8r]

allright, still havent had time to check it, im haveing another problem with my fuel gauge wich i might post in a new thread if i dont get it figured out

[frantik]

(This relates to EFI Accords)
A solid-state fan controller/timer, located under the right front seat, uses input from the radiator fan timer/temp. switch to operate fan relay. The fan controller/timer also uses input from the radiator fan temperature switch to operate A/C condensor fan relay. Both relays are located in underhood fuse box. No testing is available from the manufacturer. Do not check resistance of fan controller/timer. Relays can be tested, but need some electrical knowledge on how to test them

Recently my LX-i's fans stopped turning on, much to my annoyment (they ran fine a month ago when i bought the car wtf) and my mechanic did a full diagnostic and determined that this part was the culprit.. sucks cause it's like $250 just for the part :wtf: the jerry-rigged solutions of having the fans just turn on with the ignition sound a lot cheaper than some solid state timer lol