How do I reverse the direction of my aux, electric fan. Want it to be a pusher not a puller. Thanks.

I submit that something is wrong...the fan in front of the condenser on my volvo is a pusher....

doesn't make sense to do it any other way..the engine fan is a puller and if the condenser fan and the engine fan are working against each other....perhaps someone installed the pigtails to the condenser fan backwards.

I agree with John, the electric fan on my 91 745 pushes air through the condenser and through the radiator. Sounds like something is wired wrong.

The fan is controled by the black relay on the passenger side strut tower. There are two relays on that tower, the one for the fan has a 16 ga. black wire with a blue stripe (light blue) and a heavy 10 ga. Gray with red strip wire ....... I think. Anyway!! Thats just for the sake of information the relay is not the problem. More than likey its a pigtail wired wrong like John said.

Good luck,
Tony T
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Tony Turner 89 Volvo 240DL 257K, 1980 Mercedes 240D 360K, 1982 Mercedes 300D Turbo Diesel 153K (R.I.P.), 2 1992 Geo Metro Convertables (I'm not sure why??)

I just read your post from further down the board.

I'm not trying to be a smart axx I just want to help you understand how it works so you can decide how best to proceed.

The 740 has a pusher fan that is controled by a relay. The relay is triggered in two different ways. There is a thermal switch on the radiator (pass side top) and there is a high pressure switch in the A/C system. If the air is on and the head pressure gets to high the pressure switch grounds the relay turning the aux fan on. When the pressure comes down the fan turns off. In the event the engine temp raises to a point the radiator mounted thermal switch closes and it grounds the relay and turns the fan on. The relay on my car was bad due to bad solder joints but was easily fixed.

I know of serveral people that add an extra switch to ground the relay and turn the fan on when they want, like in heavy stop and go traffic. It seems a bit pointless to me but they claim it works to bring the temp down and make the air work a little bit better.

If you just want better A/C preformance at idle and low speed you may want to read the 740/940 FAQ. The A/C section has a link to a VOV that works wonders for increasing A/C preformance. http://www.brickboard.com/FAQ/700-900/HeatingAirConditioning.htm#VariableOrificeValveAddition

I have not used it on a Volvo but it works great on GM cars.

I hope this helped.

Tony T
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Tony Turner 89 Volvo 240DL 257K, 1980 Mercedes 240D 360K, 1982 Mercedes 300D Turbo Diesel 153K (R.I.P.), 2 1992 Geo Metro Convertables (I'm not sure why??)

Should be as simple as swapping the wires. If you hook up an electric motor backwards it will run backwards. Can I ask why?

Mark

On a previous thread I wanted to make certain I was benefiting both the AC condenser as well as the cooling system as a whole. The fan is in front of the condenser (behind the grill) and is currently pulling air from the condenser. It was recommended that I utilize the fan as a pusher based on the fact my belt driven fan is moving air one way and the electric fan is moving air the opposite way which could lead to potential problems at some speeds. Seems to make sense to me.

Makes solid sense to me but you may need to do more than just spin the motor in a different direction. It seems to me that if a fan is designed as a puller then it is designed to move air in ONE direction. If you simply spin it the other way it may not be very effective. I would think that to be the most effective as a puller you would need to have it on the inboard side and that does not seem entirely practical either. I would rewire that sucker and spin it up and see just how much air it does move in the direction that you want it to.

Mark

I will give it a shot and let you know how it went. Thanks for the input. Robert 1988 240 DL, 1990 740 GL