quick question re rad fans

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cushers
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quick question re rad fans

Post by cushers » Sun Apr 24, 2016 6:48 pm

Hi All

Given the van a few runs this weekend for about 30 minutes each time. It's not the warmest day over here but I thought / expected that the rad fans would come on. Bottom rad hose was hot. Recently had every coolant hose replaced. Is there a handy way to check that the rad fans are operating correctly?

TIA
Graeme
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Re: quick question re rad fans

Post by g8dhe » Sun Apr 24, 2016 6:59 pm

Turn on the Air Con. that forces the fans on at slow speed to allow cooling of the refrigerant even when stationery.
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cushers
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Re: quick question re rad fans

Post by cushers » Sun Apr 24, 2016 7:07 pm

Geoff, would that work and turn the fans on even if the AC system didn't (no refrigerant)

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Re: quick question re rad fans

Post by g8dhe » Sun Apr 24, 2016 7:15 pm

Ah never not had a working system! I would think it would always come on but can't be totally certain.
Geoff
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Re: quick question re rad fans

Post by teenmal » Sun Apr 24, 2016 8:11 pm

Unless the AC system is pressurised (full of refrigerant ) the radiator cooling fans will not operate via the AC control, one way you could test them is by disconnecting the connector from the ECT sensor supply wire/cable.
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Re: quick question re rad fans

Post by Northern Bongolow » Sun Apr 24, 2016 9:29 pm

get the bongo up to running temps then rev for 2 mins then off revs, repeat several times so the bottom hose is really hot then turn off the engine, leave for a min or 2 then just turn the ignition on but do not start the engine, the fans then usually come on.

or.

if the aircon doesnt work you can remove the brown plug on top of the unit at the front right hand side of the aircon radiator, short out the plug end with a short bit of wire then turn on the aircon the fans should then work with the ignition on. this is also a good way to test the aircon system, this bypasses the pressure switch if the system is sound but just has a lack of gas inside.
cushers
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Re: quick question re rad fans

Post by cushers » Sun Apr 24, 2016 9:36 pm

Thank you all.

I will let you know how I get on

Graeme
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Re: quick question re rad fans

Post by cushers » Sun May 01, 2016 3:58 pm

So I did the aircon bypass via the brown plug. I got a solenoid click then a couple of second later the right hand fan came on. Repeated this a couple of times. Nothing from the left hand fan. All this to be expected. I didn't run for long.

Graeme
Thanks for help so far
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Re: quick question re rad fans

Post by Northern Bongolow » Sun May 01, 2016 5:36 pm

the front fans are if im right in saying independent. the driverside one comes on first, then if still getting hotter the other comes on to help out, then if still getting hotter both come on at a much higher speed, the 2 fans are also different in that they have a different amount of blades on.
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Re: quick question re rad fans

Post by teenmal » Sun May 01, 2016 5:43 pm

You have just tested the AC fan, if you want to test the rad cooling fan this can be done by disconnecting the connector from the ECT sensor supply wire/cable, the LH fan should run.
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Re: quick question re rad fans

Post by teenmal » Sun May 01, 2016 5:45 pm

teenmal wrote:You have just tested the AC fan, if you want to test the rad cooling fan this can be done by disconnecting the connector from the ECT sensor supply wire/cable, the LH fan should run.
Sorry for sounding like a parrot :lol: :lol:
cushers
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Re: quick question re rad fans

Post by cushers » Sun May 01, 2016 7:03 pm

Ah, Thank you.

Sorry for being a muppet. At least the AC fan runs (not that it's much use as my AC is caput).

To further show my ignorance, is the connection that I need to disconnect the plug that is visible when looking from above?

Continually in your debt,
Graeme
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Re: quick question re rad fans

Post by cmm303 » Mon May 02, 2016 2:41 am

The sensor that controls the fans (and other stuff) is on the driver's side of the engine, towards the rear, immediately above a middling diameter coolant hose.

In the centre of this photo towards the top. Visible immediately below the horizontal red wire.
Image
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cushers
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Re: quick question re rad fans

Post by cushers » Mon May 02, 2016 12:56 pm

Thank you will let you know how I get on
Graeme
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Re: quick question re rad fans

Post by cushers » Sat May 14, 2016 6:18 pm

So finally got out to have a trip and dive under the hood.

After the trip back at a good temperature I turned the ignition back on after stopping and the right hand fan ( as you look from the bumper back in to the engine bay) came on to cool the rad. [-o<
Undid the plug pictured above and the scavenger fan came on plus the right hand side one AGAIN. Still nothing from the left hand side rad fan.

Thoughts? Worried?
TIA
Graeme
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