Does anyone know if the stock radiator fans are able to reverse the direction they are spinning? I wasn't sure if they were or weren't and I can seem to find the answer in any of the serches I do. ANy help would be great. Thanks guys.

 

I am not sure but I think you could just reverse the polarity. basically switching power and ground.

 

I know how but my question is can this be done on our fans?

 

I don't know what more of an answer you want. I don't think anyone has tried this before so try it and see how long they will last.

 

It's a common mistake made by people who wire up fan switches. Reversing polarity will make our fans spin backwards. I've seen a couple threads of FDs lost or nearly lost to people doing that.

 

Is there any reason as to why? I mean are the fans not capable of spinning the other direction for long? I have worked on a lot of cars in my day and we have almost always been able to switch the polarity and had them spin the other way but I don't want to risk losing my enigne over it...I was just curious if anyone has done it successfully without any problems? I appericiate the tips though seriously. I jsut have all this stuff wired up now and in great placement and didn't want to replace the fans unless I absolutly have to. Anyone done this?

 

Because when you reverse the flow of air, instead of pulling cool air from the outside world into your engine bay, you're pulling hot air off the block/turbos into your already hot radiator. RX-7s are very very picky about coolant temps. Much more so than most piston engines.

 

It's just a DC motor. There should be no reason that they can't.

 

These fans are DC so it will reverse direction if the polarity were switched. In doing so on the FD, your motor will overheat in no time and blow the coolant seals long before the fans ever fail.

Also the fans will be working extra hard trying to force the engine air against the incoming air when the car is moving forward.

Test out the fan leads by clipping aligator leads from the battery and see which way the fan spins.

 

These fans are DC so it will reverse direction if the polarity were switched. In doing so on the FD, your motor will overheat in no time and blow the coolant seals long before the fans ever fail.

Also the fans will be working extra hard trying to force the engine air against the incoming air when the car is moving forward.

Test out the fan leads by clipping aligator leads from the battery and see which way the fan spins. I did that to make sure the leads are correct.

 

I should have told you guys I put my radiator standing straight up and the fans are now pulling air through the radiator rather then pushing it through. This is the reason I am trying ti figure out if they can be reversed. Either way it sounds as if this should be a problem. I will try it out and let you guys know what happens. I run both fans full time so i doubt they will both blow at the same time. Either way if anyone else has tried this and had any problems please let me know.

 

^^uh. the fans are suppose to pull air from the rad, not push it through. unless your fans are now mounted on the front side of the rad reversing there direction is gonna do u more harm then good. the fan blades are also curved to operate in one direction, they would be way less efficient turning in the opposite direction.

 

Your right there I mixed up my wording. I disagree on the angle of the blades though. I personally feel that if reversed the blade design on the stock fans would still be sufficiant for the needs of a RX7.

 

I wouldn't do that unless I had a water temp gauge to be sure the cooling system is better off.

Dave

 

Fans are actually less efficient "pushing" airflow through a heat exchanger than they are "pulling" it from the opposite side. The reason is because when "pulling" airflow, the fans are using the higher pressure (hopefully the heat exchanger is mounted in a way that exposes it to direct airflow) on the opposite side to their advantage when they generate a negative pressure on their side. When they're "pushing" airflow, they're attempting to add pressure, which is much more difficult. Not to mention the fact that the fan assembly is also blocking some airflow when it's mounted in a "push" fashion...

 

In addition to the fans not functioning efficiently, having your fans (and fan mounting encasement) in front of the radiator will block some of the radiator. This will make your cooling system even more inefficient.