Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: Anonymous on December 23, 2005, 09:39:45 PM

Title: Electric fan Question
Post by: Anonymous on December 23, 2005, 09:39:45 PM
What temp does the secondary fan kick in on a 4litre XJ?
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Post by: Mike Pavelin on December 24, 2005, 07:43:17 AM
Any temp if the A/C is on or you are on defrost
About 205F if not
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Post by: Anonymous on December 24, 2005, 08:48:17 AM
bugger, will have to get a fan controller then :roll:
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Post by: chrisjones on December 24, 2005, 10:25:20 AM
Or if it's like several i've seen (Includding Barbie) any time it feels like it! :roll:

Barbie's cuts in for about 10 seconds every min or two. Still seems to work on the temp, but otherwise....on....off....on.....off :?
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Post by: Anonymous on December 24, 2005, 10:54:50 AM
that'll be when you have the screen vent on, it turns on the AC for you, looking as re wiring the fans to work on temp only
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Post by: Mike Pavelin on December 24, 2005, 12:33:23 PM
What's the problem?

I'm asking because the fan is controlled by the engine management  computer, not a seperate controller. There is a fuse and relay in the fuse box under the hood, and the engine controller uses inputs from the temperature sensor neat the thermostat, inputs from the pressure switches in the A/C system and the A/C control panel to determin when it is needed. During normal operation the electric fan seldom comes on unless on A/C or Defrost. If you have A/C on and the fan is cycling on/off every couple of seconds, the A/C is low on refridgerant. The viscous fan is sufficient to keep the engine cool especially in winter. Non A/C 4.0s manage without the electric fan because they don't have the A/C condenor obstructing flow through the radiator.
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Post by: Anonymous on December 24, 2005, 02:07:55 PM
no problem, I just want the ability to switch off the fans when wading so waster doesnt get everywhere and disable the A/C when the heater is in the defrost/screen position.
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Post by: Hoodoo on December 24, 2005, 02:23:14 PM
Steve,  Why does everyone want to be able to switch their fans off in case they start up in water? I've never had this happen. As long as the fans are off when you enter, they're unlikely to start up when the rad is receiving nice, cooling water!
  Mind you, even if they do, my fans are pushers, not pullers!
 Regards,
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Post by: Anonymous on December 24, 2005, 02:26:16 PM
as demonstrated in the great white whale at ribbo viscous fans send lots of water back on the engine, not good for petrols. Plus with electric I may gain an mpg or 2  :D
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Post by: Hoodoo on December 24, 2005, 07:46:31 PM
Then make it a temperature controlled pusher. Avoids the problem (practically certain!!) of forgetting to switch it on at the appropriate moment! I believe Pacet do some good water resistant ones.
 Regards,
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Post by: elvis on December 26, 2005, 09:27:48 AM
are you a sucker then :?:
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Post by: Hoodoo on December 26, 2005, 06:35:20 PM
Nope, a pusher! Nothing quite like a good push!! :lol:
 Regards,