4 cooling fans instead of 2.. Pros/Cons?

[4G63 For Me]

Okay, I have a question for all you smart people out there. My car has an overheating problem because I can't get enough air flowing through the radiator thanks to Mr. FMIC. I have 2 slimline fans on the inside (pulling air through). My question is, would 2 more on the other side (between the rad and FMIC) blowing air THROUGH the radiator help at all?

I need to do something, I can barely get to work in this damn heat without my car hitting around 230-250 degrees (and that's driving vac the whole time).

 

[sbiggi]

My brothers car used to over heat. We run 1 stock fan and a slimline pushed on the drivers side, but that alone wasnt enough. My brother ended up cutting two holes in the front of the bumped to allow more air over the intercooler. It did the trick for him.

I run with out the center piece between my lights, otherwise my cars get hot with the A/C on in the summer with my frontmount.

 

[Big Woo]

There are many cars out there with a FMIC and one or two fans that never think about overheating.

Unless there is a blockage somewhere, preventing your two fans from drawing in enough air. and assuming that you are running at least 10" or 12" diameter fans, and are suppling them with enough voltage for proper RPM, then your problem may lie elsewhere.

You may want to do a cooling system test, and verify the condition of the thermostat, radiator, and water pump. You may also want to check the fan switch to make sure that it is switching the fans on at the correct temp. Check the radiator for blocked passages, and or missing/rotted fins. Verify at what temperature the thermostat opens.

 

[djsven]

Hi,

This might sound dumb, but make sure they are connected in the right way. Not that you have them installed to push the air and connected to pull. Or the other way around.

Sven

 

[Turbo Talon DL]

I've read about people with only one single 12" or 14" fan with no problems, but then again you didnt say what kind of radiator and cooling mods you have either. I dont think 2 extra fans will do you any good. If anything, just run a relay to them and juice em off the battery, that'll get em going that is, if voltage/current supply is your issue.

 

[Game Over]

I'd check the thermostat or flush the radiator, and hose it out. You could also cut holes in the bumper, or run dryer hose from the side air dam to the radiator(which is what I'll be doing this summer).

 

[anconover]

4 fans will not do you any good versus 2. If you are overheating with 2 slimline 12" fans, and have tried redline water wetter and a 180* thermostat etc, your next option is a fluidyne radiator.

I have a 3.5" thick core, stock radiator, and 1 12" slimline fan with no problems. In bad traffic itll get warm, but was 80*F today and didnt have a problem around town.

 

[Diplomat]

I don't know how many CFM the stock fans pull which makes it tough to compare them to your slimlines. There are guys here who drive around all summer long on FMIC's with stock radiators and fans, and we're talking Florida heat. Like others have suggested, start checking different areas of your cooling system, and some WaterWetter® might not be a bad idea either.

 

[4G63 For Me]

They are 12" diameter fans, supplied with power from the stock fan wiring. They are definitely pulling air through and pushing it into the engine bay. I know the thermostat functions, but it may not be opening at the right temperature. I'll replace that.

I'm pretty sure it just isn't getting enough airflow. When my car gets up to about 230-240 and the CEL comes on (DSMLink), if I put it in neutral and coast down a hill, the car cools down rather quickly (10 - 20 degrees, maybe more depending on how long the hill is and how fast I'm going).

I'm getting my water pump replaced soon. Does anybody know of a place that sells aftermarket water pumps, if there even is such a thing? I've thought about a Fluidyne Radiator, but am not sure I'd have enough room or if the improvements would even be worth the $400.

 

[99gst_racer]

4G63 For Me - I am currently running a stock radiator with only one 12" fan and I have a 3.5" thick FMIC, and I've never once exceeded 210 degrees. You definatily have a problem, and I doubt it is because of your fans or FMIC. I would recommend checking everything that Big Woo mentioned --------->

You may want to do a cooling system test, and verify the condition of the thermostat, radiator, and water pump. You may also want to check the fan switch to make sure that it is switching the fans on at the correct temp. Check the radiator for blocked passages, and or missing/rotted fins. Verify at what temperature the thermostat opens.

 

[anconover]

colder thermostat perhaps? water wetter is a big help too. Use mitsu OEM water pump. Trust me, dont use that topline garbage.

 

[4G63 For Me]

colder thermostat perhaps? water wetter is a big help too. Use mitsu OEM water pump. Trust me, dont use that topline garbage.

This is the second OEM pump that has developed a bad bearing. That's the reason I'm replacing it, and why I am looking for an alternative. I know it doesn't help my overheating problem, but this problem is older than either of those pumps. Summers are the worst because Colorado is notorious for having cold weather <= 6 months out of the year.

I'm using the stock radiator, with two 12" slimline fans (~1300 CFM each allegedly) set to pull air through the radiator. I've had the AC condensor removed. Tried water wetter, didn't make much of a different (if any). Shops want ~$100 to flush the radiator and I don't have time at all during the week to do it myself, and barely any on weekends (I work 70+ hours a week).

I'm tired, I need some sleep. I didn't even see half the posts in this thread. Thanks for all the responses.

 

[overboost_dsm]

4G63 For Me - I am currently running a stock radiator with only one 12" fan and I have a 3.5" thick FMIC, and I've never once exceeded 210 degrees. You definatily have a problem, and I doubt it is because of your fans or FMIC. I would recommend checking everything that Big Woo mentioned --------->

I was having the same problem with over heating. This is set up that i am using in my 1g. With A/C. 2 slim fan one 14" on the radiator pulling air out. Second 12" in front of the a/c condenser pushing air in. I have jet had any problems. I drive 30miles to work each way.
i bought my fans from SBR.

 

[Turbocharged]

Run a relay to the drivers side fan and put a switch inside the car to turn the fan on. All you need to do is tap the stock wiring harness with a power/ground lead straight from the battery then run a relay to a switch inside the car. This is what I did and now whenever I see the water temps raiae I flip the switch and the tempurature drops to normal in a couple of seconds. Basically the fan will behave just like stock (turns on with AC ect.) except you can turn it on whenever you want (but at a greater voltage because its connected directly to the battery).

I also ran the switch through the ignition ACC power lead with the turbo timer. This allows me to keep the fan on when the turbo timer is counting down. When the car shuts off so does the fan.


I have 1 12" spal fan on the drivers side and the stock fan on the passenger side.

 

[Agent11br]

Several ideas, some of which may have been mentioned:

1. cut out / remove your bumper support, that will stop a ton of airflow

2. run ducting

3. clean out / do some maintenance on the cooling system

4. make sure the slim line fans are completely flush with the radiator. Even a 1/2 gap will make a HUGE difference

5. go to vfaq and do the fan wiring mod/ or use your link setup so that you can run BOTH of the fans all the time if needed

6. I dont know if this would make a huge difference, but running the stock or some type of turbo, mani, 02 heat shields will also help keep temps down

I run a fmic, have the manual dual fan mod were I can turn both of my stock fans on, cut out the entire middle section of my bumper support and part of the front bumper opening and I can run a constant temp of as low as 192', and thats on a warm day. Cutting out the bumper made a big difference and control over the fans which you should have with link should also help as long as you are utilizing both of them at the same time.

 

[Defiant]

It will also help to fabricate ducting around the edges of the radiators so that all the air has to flow through them instead of spilling out around them.

 

[thegreatms]

maybe go with a electric water pump like this:

http://www.racerpartswholesale.com/elecpump.htm

 

[anconover]

your blowing bearings out of brand new OEM water pumps? you have a problem somewhere. I turn my car to 8k and my water pump is fine. I even sat in line at burger king today in the sun for 15mins when its 86* out, 1 12" fan and a stock radiator, peak 50/50 coolant. You have something wrong.

 

[crashed97tsi]

do you have a gap between your radiator and intercooler? When I had a front mount on my car(it was taken off due to piping problems, not the overheating) my car used to overheat in 85 degree heat. I made a duct to force the air through the radiator after it passed through the intercooler. You can do it with a couple pieces of sheet metal and a mig welder. This fixed the problem for me after hardwiring the fans failed. Like any liquid, air will flow the route that has the least resistance. Unless you force it in there

 

[4G63 For Me]

your blowing bearings out of brand new OEM water pumps? you have a problem somewhere. I turn my car to 8k and my water pump is fine. I even sat in line at burger king today in the sun for 15mins when its 86* out, 1 12" fan and a stock radiator, peak 50/50 coolant. You have something wrong.

Yep, that's why I'm posting here. Generally, my car runs fine when I'm at a stop or going very fast. When I'm stopped, I guess there just isnt enough heat to overheat, and when I'm going fast, I can shift to neutral and coast occasionally to cool things down.

I think I will go with the combination of (after replacing the waterpump and doing cooling system maintenance) cutting some/all of the bumper support out, and fabricating a duct from the intercooler to the radiator (or around the radiator, like Defiant suggested).

I appreciate the help/suggestions from everyone. Hopefully I'll get this fixed so I can start worrying more about tuning than overheating.

 

[danielbui]

vent your hood or buy a prefabed vented hood. that has cured alot of overheating problems.

 

[rob_rousseau]

Have you put in a new t-stat yet? It's very easy, 2 bolts and 1 gasket, and cheap enough to do no matter if you think the current one is "good" or not.

 

[KlowdDragon]

Run a relay to the drivers side fan and put a switch inside the car to turn the fan on. All you need to do is tap the stock wiring harness with a power/ground lead straight from the battery then run a relay to a switch inside the car. This is what I did and now whenever I see the water temps raiae I flip the switch and the tempurature drops to normal in a couple of seconds. Basically the fan will behave just like stock (turns on with AC ect.) except you can turn it on whenever you want (but at a greater voltage because its connected directly to the battery).

I also ran the switch through the ignition ACC power lead with the turbo timer. This allows me to keep the fan on when the turbo timer is counting down. When the car shuts off so does the fan.


I have 1 12" spal fan on the drivers side and the stock fan on the passenger side.

you got there before me, haha, yea this is a good idea for anyone to use, make a switch for each fan you have and you will be able to control temps alot easier, and if your getting ready for a race you can turn on the fans even if your temps are low

 

[4G63 For Me]

Here is an update. After the two cooling fans and water wetter didn't help, and flushing the system numerous times, removing the radiator and spraying it down and washing it out with no change, I decided to remove the thermostat (I couldn't get a replacement, so I just removed it). The overheating problem stayed the same (although it took an extra minute or two to get to that temperature). So I went and got the bumper support removed, and got the bumper trimmed so the airflow could go up over the intercooler and to the radiator. It still overheated (although it helped to cool the car down a bit faster). So one day I decided to order an OEM radiator. I put the two fans on (one of the cooling fans was pushing air from inside the engine compartment into the radiator, so I put that on the other side so its pushing cool air through the radiator and into the compartment), I flushed the system, and went for a drive without the heater on. Hour and a half of hard driving later (in around 70 degree weather), the car still wasn't at the middle mark. It got there a few times, but cooled down soon after. Occasionally it was at 1/3 the gauge, which I'm sure has to do with running without a thermostat. I will put a new one of those in soon.

Guess my old radiator was shot. Best $180 I've ever spent. It is SO nice driving without the heater on. Thanks for all the help everyone. By the way, I'm still running with a leaky, on its last leg water pump. I get that replaced Friday.

 

[notractiongst]

temperature). By the way, I'm still running with a leaky, on its last leg water pump. I get that replaced Friday.

and you couldnt figure out why it was overheating?