Electric fan upgrade - Pros & Cons?

[doctorj240]

Lol... man I can't wait until f&f 2. It'll be a good laugh I'm sure. As much as everyone hates it, everyone is still going to watch it just to make fun of it. Anyways... back to real cars. I've read some stuff in the forums and elsewhere (I don't know exactly where), but it sounded like you had a good scene up north. By the way, I'm signed up now as supraman09.

[s14=pimpin']

AWESOME!!! Glad you signed up, put up a post with your ride, what you've done, and your long term goals. You'll make some friends real quick. Oh, I'm paulb78. Guys to talk to

Adam H. - he purchased his s13 brand new in '89, still has it, turboed it and autox's. He's top in his class, knows alot about turbos

Dan N. - just installed a SR in his s14

Jonathan H - just put a turbo kit on his s14, very smart guy and knows quite a bit, just doesn't post very often

David W. - his car is still NA, but he is always willing to help

John and James - These 2 guys are pretty popular cause they had a SR in their s13 about 2 years ago, so everyone in the club knows them. Fun guys, know alot about turbos, but don't see them very often.

Everyone else can help you out with electronics, deals, driving techniques and even engine swaps

welcome to the club

and I think some cali guys may get offended cause you didn't mention them in the towns with fast 240's



did you see the pics from our last gathering? Go into 240 general, I posted a thread with a pic of my ride, follow the link and check out the rides. 2 SR's came out, pics at the link.

[Julio Bro!]

Originally posted by Julio Bro! "]The electric fan is engine

condenser

temperature based, it turns on if the engine

condenser

reaches a certain temperature

If this is for sure, then it should be a combination of engine and A/C temperature, after all it's installed behind the radiator and complementing the main fan.

Is there a temp sensor on the condenser or it's lines? Where?

[Julio Bro!]

hey, thanks alot guys

still a little confused though. Julio says its not worth it, but I'm not tuning my KA until I've come to a conclusion on what turbo to use. I figure its a universal fit, so even if I do swap, I can use it on another motor, correct? It is a nice fan, although I am buying it used, so I will have to take a look at the connections, thanks again.

240sxer, are you currently using a fan? Thanks for the info, the main reason why I wanted to replace the stock unit was to free up space so I can use my homemade CAI, the stock fan is so big, and ordering from Injen is no fun!!!

cya guys

I didn't say it's not worth it, I said that I would not change it.

There are people that would because it frees the engine a bit, particularly if you change to a light weight damper and the other belt wheels.

[Julio Bro!]

I guess this makes sense but the best sports car isn't running through stop and go traffic with no air flowing through the radiator on hot city streets. They're zipping around at 150 mph flowing plenty of air through the engine bay.

Oh yeah... I know there are turbo 240s running only a 12" fan. To be safe though I would not go with a 10 if you plan on upgrading, go with at least one 12".

Zipping around at 150mph would be a good reason to use the electric, it would usally be off. Traffic and hot streets should ask for a belt drive. Again, this is a reliability and force thing.

[Julio Bro!]

The fan turns on low speed at 202 degrees, high at 212, OR when the AC is on. Your fan should be on whenever the AC is on. That fan is fine for cooling on it's own, but an upgrade to a pair of fans, or a larger unit will cool more.

The electric fan system is "active" when the A/C is on, but it actually runs when the temperature rises, it's not always running. You can see it turning on and off.

Changing the stock system for an electric system only, should work with a temperature or "on" signal from the computer. Although I guess most of them are selfcontrolled and switch on their own; in this case I would check what are the temperatures at which the car would need them to be working and get a system accordingly.

[Julio Bro!]

Originally posted by Julio Bro! "]If this is for sure, then it should be a combination of engine and A/C temperature, after all it's installed behind the radiator and complementing the main fan.

It is for sure, and it's not dependent on the engine temperature.

I've been working on AC units for almost as long as I've been working on cars.

Is there a temp sensor on the condenser or it's lines? Where?

Check your FSM, it's noted in there. HA-42 in the 1990 manual, I don't know what year you have.

1993 - I have the manual, I'll check it out. Thanks for the lesson; then my statements change to condenser temperature only.

That would mean that if an electrical system could use the computer signals, then both temperatures would have to be used. That would be an interesting application.

[GodDrivesA240sx]

Also, mine appears to have some sorta stock electric fan that's in front of the clutch fan, i've never seen it on, but what's that about? Is it for when the AC is on?

David.

That would be the fan for your condensor, when your AC is on it should turn on to help provide airflow for the condensor at low speeds

[SRJesse]

I have 2 electrical fans on my sr20det setup. The only "con" that I can list is if the engine is still warm when you park it and shut it off, the fans will run off the battery until the sensor reaches a point and they shut off (depending on temperture). You can get a relay at radio shack or any electronical store for like $5 and they will shut off when you shut your car off, that way you get rid of the only "CON" I can tell you about.

Hope this helps with your final decision. Good luck.

[240SXer]

I have 2 electrical fans on my sr20det setup. The only "con" that I can list is if the engine is still warm when you park it and shut it off, the fans will run off the battery until the sensor reaches a point and they shut off (depending on temperture). You can get a relay at radio shack or any electronical store for like $5 and they will shut off when you shut your car off, that way you get rid of the only "CON" I can tell you about.

Hope this helps with your final decision. Good luck.

I'd think that would be a pro. It's not hard to make it not do it, just wire the fans to something that is hot only with the ignition. But wouldnt it be better to have it run till the car is cool even if it's off? That's the way I WANT mine wired, that's why i'm not going to use the stock relay.

David.

[ash1y1]

So where did you guys purchase your electric fans from and how much did they cost?

[Nils]

to the original post:

To be able to answer the question we really need to know what you are building the car for. Is it a street car that will see occasional drag use? a auto X car? a road racing car?

IMO ... oem/belt style fans can flow more air than a electrical fan. The electrical fan will clear up alot of space though. If you are not planning on road racing or auto X'ing you car the electrical fans will be ok, but, if you are planning on attending track days I would stick to the stock fan assembly.

take care,nils

[TooSicks]

I've been considering switching to electric fans, as well as an electric driven water pump. I'm thinking about 2-12" with a standalone thermostat system and also an electric water pump drive motor. Summit sells an electric motor with a drive belt that drives the water pump on a chevy 350 but i'm sure i can make it work on my '89. has anyone else ever seen or used an electric water pump on a 240?

In my experience and opinion I think the electric fans are more reliable than a belt driven setup, as i have had many mechanical fans shed blades,crack and warp, and eat fan clutches with regularity. My toyotas, hondas, and my ford tempo all used electric fans and I never had any fan related cooling issues with any of these, even when driven hard and kept on boil, at the strip, on the roadcourse, or in rally racing conditions. I haven't had much nissan experience but in my general experience the only fan problems I have ever had were with mechanical setups. my chevy venture actually shedded a blade at 75 mph on the highway, dented the hood, and dstroyed the water pump whichj led to an extremely rapid temparature increase that caused a head to warp.

[Julio Bro!]

I've been considering switching to electric fans, as well as an electric driven water pump. I'm thinking about 2-12" with a standalone thermostat system and also an electric water pump drive motor. Summit sells an electric motor with a drive belt that drives the water pump on a chevy 350 but i'm sure i can make it work on my '89. has anyone else ever seen or used an electric water pump on a 240?

In my experience and opinion I think the electric fans are more reliable than a belt driven setup, as i have had many mechanical fans shed blades,crack and warp, and eat fan clutches with regularity. My toyotas, hondas, and my ford tempo all used electric fans and I never had any fan related cooling issues with any of these, even when driven hard and kept on boil, at the strip, on the roadcourse, or in rally racing conditions. I haven't had much nissan experience but in my general experience the only fan problems I have ever had were with mechanical setups. my chevy venture actually shedded a blade at 75 mph on the highway, dented the hood, and dstroyed the water pump whichj led to an extremely rapid temparature increase that caused a head to warp.

Man, what are you doing to your cars? You are the Fan Devil.

[s14=pimpin']

LOL, still haven't upgraded my fans yet, I may do so in about 2 months. I'll keep you guys posted, I'm really doing it so I can finally install my rip off injen CAI, but its winter now, I have plenty of time. And who the heck resurected this thread, man, it was buries pretty deep!



take care guys, any input regarding this upgrade is much appreciated.

[TooSicks]

i ressurected it, and yeah it was pretty deep but i found it, hey, i was bored and didn't wanna start a new thread since there already was one.

Peace

[s14=pimpin']

LOL, no worries man, and its better that you dug it up, rather than start a new one, good call! Everyone would have hammered you to do a search.

good luck

[TooSicks]

So has anyone run an electric water pump on the 240?

[s14=pimpin']

whoa, not to my knowledge.

[Julio Bro!]

Originally posted by Julio Bro! "]If this is for sure, then it should be a combination of engine and A/C temperature, after all it's installed behind the radiator and complementing the main fan.

It is for sure, and it's not dependent on the engine temperature.

I've been working on AC units for almost as long as I've been working on cars.

Is there a temp sensor on the condenser or it's lines? Where?

Check your FSM, it's noted in there. HA-42 in the 1990 manual, I don't know what year you have.

The truth about the 1993 240SX A/C system as presented in the FSM.

The electric fan is solely controlled by the car's computer, it has an output dedicated to activate the relay that starts the fan.

The computer receives the following: Engine's water (coolant is what the book says) temperature, Throttle position and Ambient temperature. The system uses all of them to decide when to turn on that fan and when to disconnect the compressor

The only other temperature measurement is from inside the car, where the blower unit and controls are located. This is for the unit that controls the temperature for the passenger cabin by managing the compressor. This temperature measure never reaches the computer.

So, no condenser temperature based system here.

Now, I did see that the water temperature sensor gives an "on" signal when a certaing temperature is reached. I think this signal maybe used to activate the relay for an electrical fan system replacing the mechanical one. That should be a better control because it's on factory specs, not aftermarket.

[Ceptos]

haha, he got u

[Julio Bro!]

OK, sorry for not replying earlier, but my phone lines are down and I'm involved at the job, but I have a break to do this.

Alright Mr. Lost_To_A_K-Car, I'm not questioning your experience or expertise on these systems, but as time passes, things change or someone may try something different because it's an improvement or a short-cut or convenience, etc. For example, some years ago Ferrari made a car with a front engine (one of their Maranello models) and in order to obtain a more balanced weight, they installed the transmission on the rear axle. I've never seen that, but the fact doesn't mean that it has never been done before or that it's not done that way. Probably for some mechanic that's never seen or heard about such a thing would say, that's not possible, that's an incorrect layout. Nevertheless, there it is, and now you can find that layout on the North American made Corvette too.

On the 1993 240SX air conditioning system matter, this is what I have:

My factory manual was "Printed in Japan" in 1992. The section is Heater and Air Conditioning, pages marked in bold with "HA". On pages HA-10 and HA-34 are detailed diagrams showing refrigerant lines and condenser system, with no temperature sensor.

On page HA-63 is the harness layout in which you can see the "Engine Coolant Temperature Sensor" and "Ambient Switch", no other temperature device. And on page HA-64 there is the circuit diagram in which you can see all the sensors in the system, including the path to every device (condenser fan, compressor, etc) and there is no refrigerant or condenser temperature sensor.

You can check and read the whole 92 pages on that section to be sure, maybe you see something I didn't. But you'll also find out that the computer is the sole automatic controller and it uses ambient temperature, engine temperature, and throttle position. Unless the whole section is wrong, that's it.

Good Luck.

[Julio Bro!]

Hmmm, I didn't focus on pressure sensors, there is something about a pressure switch. I'll check on that and see what's it contribution to the system; but this is a different measure, it's not temperature.

And again, understand that I'm stating that these devices are controlled by the computer, it signals the different relays so things turn on or off; that's what the factory manual says, it's not my opinion or what I believe. There is no independent circuit (from the computer) activating the fan and the engine temperature sensor IS received by the computer to make decisions regarding the A/C system, because it's shown as an integral part of it.

I don't have a scanner so I can't put those pages here; you being the proffessional in automobiles I suppose you would try and get this manual or someone that has seen what I'm talking about.

Maybe that pressure signal is also registered by the computer and goes into deciding when to turn on the fan, but it's definitely NOT connected directly to the fan.

[Julio Bro!]

The Thermo Switch present in that 90's model diagram is NOT present in the 93, in fact there's nothing between the fan and the computer signal, only the relay. The relay becomes active with the A/C switch and the "ON" signal is given by the computer.

I'm an electrical engineer, I have some experience reading technical material and circuit diagrams, this is not a misinterpretation, that is what the manual has in its pages.

Now, the fact that you can derive temperature from a pressure sensor is not the same as stating that there is a condenser temperature sensor or that the pressure sensor is used for controlling a fan. Nonetheless, I have to look again at the diagram to see if the pressure switch contributes in anyway to the computer's analysis. My feeling is that this switch is more of a safety device, in case there's too much refrigerant pressure in the line's; I don't remember seeing that the computer received this signal.

[Julio Bro!]

Well, it could be a bit different, as you know, even the compressor is special; it's a variable pressure unit. And I don't mean that it changes pressure with the engine's turn, it has an internal plate that can modify the volume in which the gas is compressed.

Regarding the logic of the computer, there is no diagram that tells how it decides. I think you're going to be very surprised when you see the diagrams and read about this system. I'm certain the engine temperature is used because the literature acompanying the HA section's diagrams, says it's taken into consideration. Maybe not to specifically turn on the fan, but in regards to the whole A/C system.

I'll try to find some place in the internet with the diagrams and paste them here, but for mere technical curiosity and probably new type of systems, you should get this manual or these diagrams somewhere. I mean, you do give serious technical advice in this forum, and we appreciate it.

[240canuck]

i've got a question my mom's 91 Stanza has the ka24e engine and the radiator looks to be the same size it has an electric fan because it is front drive and the oldr altima's aswell have the ka24de engine could the whole systems be ripped from a donor altima or stanza and be replaced into the 240sx just a question cause these cars are designed to not over heat or have any problems with electric fans using the same engines as our 240's is this a viable option. i bet its pretty cheap to get a stanza fan and whatever other parts you need from a wrecker. (also what other parts would you ned to convert over to elctric other then the fan it self?)

[1991240xs]

240 canucks question is good..cause my girlfriends mom's car is like that...let us knowalso...if i install my own..how much for a decent 12 inch should i be looking to pay? How do they mount. And would you take off that fan that is currently in front of the mechanical fan? any writeups on wiring one up? what do you do to the old mechanical fan..just take of the blades or what?(clueless)Also..would I buy a puller or a pusher to put in?(I plan on buying one 12 inch..not two)

[Julio Bro!]

Hey Lost_To_A_K-Car, I have the diagram, but how can I paste it here? I'm trying copy/paste, but this site won't take it. I tried attaching, but reducing the image to 400 pixels, makes it loose resolution when blowing it up. How you transfer an image to the reply window?

[Julio Bro!]

Oh, if you have a subscription to ALLDATA, you can see the diagram there too and zoom.

[Julio Bro!]

OK, this is it, I'm attaching the diagram reduced, I hope it's visible. I checked on the Dual Pressure Switch, is a safety measure that turns off the system when excess refrigerant pressure is detected.

Analyze carefully. See a condenser or refrigerant temperature sensor? See the Engine Coolant Temperature Sensor? What's connected to the fan relay?

I think Mr. Lost_To_A_K-Car that this concludes the issue, we could discuss further, but check this out carefully first. The diagram is from ALLDATA and it's the same found in the factory manual.