Printable Version of Topic

Posted by: ventedrib May 15 2013, 11:52 AM

I have a subie powered 73, I have been running the dual radiator fans directly off the battery. The fans are renagade hybreds fans they have there own relays and turn on and off with a thermostat in the radiator. This works good but I don't like that the fans run for 4 or 5 minutes after I turn the car off. I no longer have headlight motors but wire to the motors is still there, I dont have a fresh air fan any longer but wiring is still there. I took the large red wire at the fuse panel head light motor and moved it to the switched fresh air fan / wideshield wiper terminal and wired the fans on to the large red wire were the headlight motors used to be. Fans came on and were swithed, turn the key off fans went off. Went for a drive came back fans not running, cked and had no voltage, pulled fuse panel and found that the relay, I guess for the wipers had pretty much melted. Swaped one of the outher relays and had volts again. Is there a way to bypass that relay since the fans have there own or put a relay at the fuse box to handle the draw of the fans, or just keep it like I had it.

Posted by: okieflyr May 15 2013, 01:22 PM

With a quick read of your post, your probably overloading that circuit with the fan amperage. Putting a heavier relay may continue that trend and the next bad wire when it catches fire. Putting a switched relay on your original power feed from the battery power.

Posted by: 904svo May 15 2013, 01:51 PM

Who's ECU are you using? Most of them have a build in fan control circuit control
using the engine temperature sensor to turn the fans off and on. Thats what I did
with my conversion.

Posted by: Cap'n Krusty May 15 2013, 04:06 PM

The fans run after shut down for a reason. You might not like it, but they bring the coolant temps down to safe levels after the water pump stops pumping the coolant around. Audis and some other cars incorporate an afterrun coolant pump in addition to the fans.

The Cap'n

Posted by: Drums66 May 15 2013, 04:46 PM

QUOTE(904svo @ May 15 2013, 12:51 PM)

Posted by: ThePaintedMan May 15 2013, 04:53 PM

QUOTE(Cap'n Krusty @ May 15 2013, 06:06 PM)

Posted by: monkeyboy May 15 2013, 11:05 PM

It's a closed system. It can still flash boil in the heads causing pressure to go up in the entire system.

Cooling the radiator helps bring the average temp down, and it will circulate very slowly on it's own. Convection cooling I think it's called.