Coolant temp rising when at idle

[Vanhack]

The temperature here in Dubai has started to rise, today's high is 38 degree, and in a couple of months, we will be seeing 45s on average, with night time temps of 35s. My coolant temperature never would go past 1/3 mark, the 2nd white line from the bottom, it used to stay at the 1st line in these temperatures. Now it reaches the 2nd white linewithin minutes of driving and almost always when at idle, drive the car in the 40-60km/h zone and the needle drops to the middle of the 1st and 2nd white line.

I suspect that the air flow is limited, checked the cowling, and the fan, all seem fine. Must be the fan clutch, and already checked the price for it, AUD 160.00, I know there is a alternative fix by drilling holes etc, but would rather replace the clutch complete, but would rather replace the complete unit.

But before I go spending the money on the clutch, would there be any other reason for the temperature to rise around idle, other than lack of airflow over the radiator. Really doing this, before the temperature gets higher here, and prevent further damage to the cooling system.

[j-top paj]

have you checked your thermostat?

[Vanhack]

No not yet, what is the best way to check the Thermostat?

[j-top paj]

pull it out and stick it in a saucepan full of water on the stove

see if it opens when the water boils

[chimpboy]

Possibly the water pump as well.

Or there's the possiblity that your radiator is a bit gunked up, and you need it cleaned or rodded.

Even little things like a decrepit radiator cap could contribute.

Does it feel like the fan clutch is stuffed? I thought they were more prone to seizing than to getting too loose; if it's seized it would not lead to overheating.

[Vanhack]

Well I tried hand spinning the fan, but as others have said that it should not spin freely, nor should it be unmovable. And hence my doubt it is the clutch.

The fan moves with resistence, around 2-3 blades move with flicking the fan.

[j-top paj]

The fan moves with resistence, around 2-3 blades move with flicking the fan.

is this when cold? ie many hours after the vehicle has been driven

[Vanhack]

The fan moves with resistence, around 2-3 blades move with flicking the fan.

is this when cold? ie many hours after the vehicle has been driven

Well from cold, and driving around 20-30 mintues, and the coolant temp reaching 2nd line on the dash.

[j-top paj]

no i mean when you turn the fan to see if the clutch is working properly

[Vanhack]

no i mean when you turn the fan to see if the clutch is working properly

yes same when cold as well.

[purplebus]

was told the best way to check fan is to get the truck up to running temp then pull over, open bonnet and watch the fan when you turn engine off. if the fan is ok it should stop almost instantly with the eng. it should also be harder to turn by hand.
also is it idling at different temps with air con on as the bearings can go in compressors and they heat right up on idle.

good luck

[lexi]

Yes but obviously that method of testing wont do for a seized or slightly seized fan just one that is loose.

Alex

[frby69]

but if it is siezed it will use more fuel not raise the temp as it acts the same as a fixed one allways spinning

[Vanhack]

was told the best way to check fan is to get the truck up to running temp then pull over, open bonnet and watch the fan when you turn engine off. if the fan is ok it should stop almost instantly with the eng. it should also be harder to turn by hand.
also is it idling at different temps with air con on as the bearings can go in compressors and they heat right up on idle.

good luck

Yes stops with less than one full rotation.

[dirtydog16]

G'Day mate,

I have a GQ Patrol and it kept starting to overheat when low range 4x4ing.

I found out it was the fan clutch by running the engine as per normal driving and waiting until the heat built up and then turned the engine off and turned the fan and it was fairly loose while hot.

To fix it I took the fan off and drilled a very small hole in the back of it and then went to Toyota and bought replacement fan clutch fluid (as the toyota landcruiser fan clutches are servicable), and then used a large syringe to insert the clutch fluid into my fan clutch body and then used a self tapping screw and some flange sealant to seal the hole.

It worked like a treat and it has not overheated since.

I think it was $10 each for I think 2 tubes of the toyota clutch fluid.

A fairly cheap fix that I am happy with although as others have said if it is too stiff it might spin more than it should and use more fuel and I don't know how the stiffness of my fan compares to an original one.

Wouldn't think fuel would worry you too much in the Emirates though. It was fairly cheap when I was there.

Good Luck!

[Vanhack]

G'Day mate,

I have a GQ Patrol and it kept starting to overheat when low range 4x4ing.

I found out it was the fan clutch by running the engine as per normal driving and waiting until the heat built up and then turned the engine off and turned the fan and it was fairly loose while hot.

To fix it I took the fan off and drilled a very small hole in the back of it and then went to Toyota and bought replacement fan clutch fluid (as the toyota landcruiser fan clutches are servicable), and then used a large syringe to insert the clutch fluid into my fan clutch body and then used a self tapping screw and some flange sealant to seal the hole.

It worked like a treat and it has not overheated since.

I think it was $10 each for I think 2 tubes of the toyota clutch fluid.

A fairly cheap fix that I am happy with although as others have said if it is too stiff it might spin more than it should and use more fuel and I don't know how the stiffness of my fan compares to an original one.

Wouldn't think fuel would worry you too much in the Emirates though. It was fairly cheap when I was there.

Good Luck!

Thanks mate, I actually replaced the whole fan clutch, as I found that the fan was basically always engaged, noticed this when revving at cold, and the fan would also increase in speed. Anyhow the cooling is slightly better, and wait until peak summer in traffic to note differences.