Electric Fan Problems!!!

Post by **bazan** » Wed Mar 26, 2003 9:05 am

I need help on my electric fan conversion. I am trying to wire the current electric fan (A/C Fan) As the radiator fan. I bought a kit from summit racing that was supposed to allow the fan to turn on at 200 degrees and turn off at 185 degrees. Unfortunately the sensor requires you to thread it into the intake manifold or head. I tried to put a t-fitting into then coolant lines near the throttle body. Now the fan doesn't work and the car almost overheated. Anyone have some suggestions. How did everyone else get the fan to turn on and off? Thanks all

Andrew

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

Thats why i have my fans wired to stay on all the time with the ignition on. Theres a coolant temp sensor on the bottom radiator hose, see if you can tap in to that.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

Thanks man, I didn't know about the coolant temp sensor. Is it electrical or what? I'll have to look at my Service Manual to see if i can use it or not. This kit i bought is a pain in the ***. Warning: Do not buy the Painless Wiring kit for electric fans from summit racing. It is more trouble than it is worth.

Any more suggestions are always welcome. Thanks all.

Andrew

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

its electrical, theres one near the intake manifold too. Supposedly one sensor is for the ecu reading and the other one is gauge reading.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

My friend and "mechanic" SR20DET240 and I are going to go buy a new sensor at Lee Auto Parts today. Kinda' broke the old one trying to solder a grounding wire to it. This way we can put it in the intake manifold without drilling and tapping, there are a couple of bolts that look mighty nice.

By the way, these sensors, which is which?

Post by **bazan** » Wed Mar 26, 2003 9:05 am

Well, I didn't buy the temp. sesor i thought i needed. I just used the relay from that kit and wired the fans for constant on. It works quite well, I was surprised. Thanks for the help NISMO1182.

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

No problem. Did you wire it constant on with the ignition or with a on and off switch?

Post by **yellow_jacket** » Wed Mar 26, 2003 9:05 am

The coolant temp sensor is a 2 wire and the temp sensor(for the guages) is a 1 wire.

Also, the temp sensor just passes neg. voltage to the gauge while the coolant temp sensor is a variable resistor that the ecu passes a voltage through to read the coolant temperature

Post by **bmxruler4130** » Wed Mar 26, 2003 9:05 am

do you have to rewire the fan or can you just leave it stock? i took out my fan and left the electric fan. i seems to work fine but i dunno about when i it gets real warm in the summer.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

you have to re wire the fan. At first i took out the old mechanical, but the car overheats real quick like that. I wired it to the ignition, not an on/off switch. I decided that this way when my dad drives the car, he won't blow it up because the fans aren't on.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

I have found that the old A/C fan is not enough to cool the engine during stop and go traffic. I took a trip less than 30 miles away, and the motor overheated twice on my way home. Both during stop and go traffic. I'll be getting a bigger more high flowing fan eventually. But for now i just gotta take it real easy on the gas pedal.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

MYTH!!!!!

All I felt was a far smoother acceleration, but no quicker. Sorry to tell you.

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

Yeah its smoother, maybe like 2 hp max gain.

bazan, have you flushed and refilled your cooing system? Today I forgot to turn my fans on, and i drove from downtown orlando to my house (15 miles trip) in mild traffic and not once did the needle move from the normal spot. Before i flushed it, the car overheated easily without the fans on, even at idling for 10 minutes. Now i can leave the car idling all day if i wanted too with out the fans on and that needle wont move past normal.

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

on mine, the relay box on the driverside, by the intake box. I tapped off the ACC. (accesory) relay wire. I think its either a blue or white wire. Check current with a voltmeter.

Post by **Open4Cycle** » Wed Mar 26, 2003 9:05 am

If you look at your local parts store they should have a thermostat fan controll system. Look for one that has a temp sensor that installs into the radiator cooling fins. It works quit well and requires no drilling and tapping. If you like to bracket race then having a manual switch to operate the fan while the ignition is off can be a very big help in the pits. Also you want a switch to deactivate the fan while ignition is on. No fan is where the performance gain is at.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

That is what i should have done but didn't. I used the fuel pump fuse in the box next to the battery for my switched on.

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

i dont think thats such a good idea with the fuel pump fuse. I hope you atleast put a inline fuse to the fans, incase the fans short out while your driving, it wont take out the fuel pump fuse with it, it will take out the inline fuse instead and save your motor.

Post by **nnkfws333** » Wed Mar 26, 2003 9:05 am

Hey Nismo, relay box? So I guess you just took the positive wire and tapped it into the wire going into the ACC?Does anyone know where I could tap power into to get the thermostat to work?

Post by **Open4Cycle** » Wed Mar 26, 2003 9:05 am

There are many ways you can do this project. You could use the factory fan relay to power your new fan provided the amperage is lower than max amps of relay. (I think there is a how to for this) You can also use most any switched circuit you would like provided you use a relay connected directly to the battery. That way your relay solenoid not your fan drains current from your switch.

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

nnkfws333 wrote:Hey Nismo, relay box? So I guess you just took the positive wire and tapped it into the wire going into the ACC?Does anyone know where I could tap power into to get the thermostat to work?

Yeah the relay box and the relay marked acc. I tapped the positive to it and put a inline fuse just in case. I ran the negative to a switch under the dash to cut the fans off when i work on the car or something.

Post by **bruinbear714** » Wed Mar 26, 2003 9:05 am

The point of the electric fan is to reduce the parasitic drag on the engine when you are cruising... and if you have it wired to be "on" all the time, that kind of defeats the purpose of getting an electric fan!

With it on all the time, you are essentially converting from using mechanical energy to using electrical energy.

Post by **ADAMHU** » Wed Mar 26, 2003 9:05 am

i ditched the thermostadt it was nothing but problems, and now use a switch

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

bruinbear714 wrote:The point of the electric fan is to reduce the parasitic drag on the engine when you are cruising... and if you have it wired to be "on" all the time, that kind of defeats the purpose of getting an electric fan!

With it on all the time, you are essentially converting from using mechanical energy to using electrical energy.

yeah but electrical energy doesnt use up hp, its only 12v anyway. Not a big power draw like say a sound system would.Its nothing your electrical system (i.e alternator) cant handle. It it was a problem, then people with aftermarket gauges, boost controller, afc's and other little things that run all the time would have problems.

Post by **bruinbear714** » Wed Mar 26, 2003 9:05 am

Nismo1182 wrote:yeah but electrical energy doesnt use up hp, its only 12v anyway. Not a big power draw like say a sound system would.Its nothing your electrical system (i.e alternator) cant handle. It it was a problem, then people with aftermarket gauges, boost controller, afc's and other little things that run all the time would have problems.

How does it not use up hp? Please explain.

Last I heard, the alternator was driven by the crank pulley through a belt.

If you want to leave your fan on all the time, that'll work... but don't think that it isn't a parasitic load because it IS. In fact, it may even eat up MORE hp than the mechanical fan.

It is far easier to turn the alternator with no load on it as suppose to turning it with a load that draws 20A, or 50A, or 100A. The energy has to come from somewhere.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

For one, the alternator under load does not use as much HP as the old mechanical fan. Therefor although you do not rid the engine of the parasitic drain, the net decrease is fairly significant.I'm having some problems. The car is continuing to overheat on me, I've replaced the thermostat twice, the first one didn't even open until 270 or so, the second one I can't tell when it opens up. If I assume the thermostat works properly, what else could cause the engine to overheat like this? Putting my hand in front of the radiator/condenser I can feel a significant pull of air by the fan, putting my hand behind the fan, I feel cool air being pushed toward the block. I am out of ideas, you guys have any? Thanks

Post by **ADAMHU** » Wed Mar 26, 2003 9:05 am

i went thru the same stuff.....i think its mostly due to the removal of the shroud...

Post by **Nismo1182** » Wed Mar 26, 2003 9:05 am

mine overheated when i switched to the electric fans. I never flushed the cooing system after i bought the car. When i did flush it out and put new coolant and water, the car never overheated again. It wont even over heat with the fans off.

Post by **Scott McLellan** » Wed Mar 26, 2003 9:05 am

First off, the goal of the cooling system should be to use as little energy possible to keep the engine at a safe temp. Engines have a certain temp. at which they perform the best (cooler is only better to an extent). Too much cooling capacity and you are wasting energy(power). To little cooling capacity and you are losing power and risking engine damage. Second, the more "stages" energy has to go thru if it be mechanical to electrical or whatever, the more energy is lost due to friction. Mechanical fans are very efficient for normal everyday drivers because since a mechanical fan has the advantage of being powered directly from the crank without going thru the alternator like an electric fan does, it doesn't draw as much power and because everyday drivers don't usually rev their engine to 6 grand like us. The disadvantage to the mechanical fan is with that rpm's factor. A mechanical fan can't choose its speed so for it to be able to move enough air for the designed-for-everyday-driver's low rpm's it will move too much air at high rpm's drawing extra power that should be sent to the rear wheels. That is where the electric fan comes in. It spins at the efficient fan rpm's and allows the engine to spin its own rpm's and draw only a little bit more power than a mechanical fan on an every-day-low-rpms-driver's engine because of that extra energy conversion of mech. to elec. at the alternator. So for an ex. say an engine is spinning at 6000 rpm's. If it had a mech. fan that turned at say the same speed as the engine it would be turning at 6000 rpm's. Say the engine only needed the amount of air that the fan would move at 4000 rpm's though to cool it sufficiently. That extra drag that the 2000 extra fan rpm's creates from moving more air than is needed to cool the engine is a power loss. Electric fans can turn on when needed and move the amount of air that the mech. fan would at 4000 rpm's and then shut off or come on less frequently when the engine doesn't need the fan's help to keep the engine cool enough.

--If you find something you don't agree with here correct it please. -Scotty

Post by **Scott McLellan** » Wed Mar 26, 2003 9:05 am

If you had the money, seems like one of those aluminum radiators from Be Cool or Griffin or something would be the ideal solution. They cool a lot better than the factory copper core things in factory cars so you wouldn't need as much "fan-power." They also weigh less. You would want an electric fan to help out in slow traffic or in hot weather but with the added efficiency of the radiator the fan would be on less creating less drag on the alternator and more hp.

Post by **bazan** » Wed Mar 26, 2003 9:05 am

I agree with eveything you've said there Scotty. I'm planning on doing a system flush sometime very soon. I've also tested the temp sensor for the water temp gauge. It is registering at 48+/- 3 ohms. It is supposed to be in the 70-90 ohm range. I'm getting a new temp sensor to be safe. I don't want to replace the radiator until I do an SR swap. Originally I was against it, but I've been considering my options since I will start college in the fall and for the power i want that seems my best choice. When I swap the motor I'll put a really good radiator in too. Thanks guys.

Electric Fan Problems!!!

Electric Fan Problems!!!

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