Overheating Problems

[bengerman]

hey locks,
yes you´re right, the dust is quite bad up here.
have already thoroughly cleaned both the radiator (which is brand new, like 1x month old) and the air con condenser, so, no dust, bugs or anything

and finly:
just to clarify...it does not get hotter when i use the heater
it gets hotter when i:
the ambient temp is quite high...early 30´s and higher
i use the air conditioning (which causes the condenser in front of the radiator to heat up...and my model does not have a thermo fan fitted factory)
i drive at speeds 100kph or over on bitumen
or 80kph or over on dirt
or am carrying or towing a load
or climbing hills
or any combination of any of these

the thermostat is the lowest factory temp option which i think is 77 or 79 deg from memory
temp send unit is factory, never been changed and seems to operate normally, bever had a problem with it

have not seen radiator boiling water yet

essentially it just appears to be getting uncomfortably hot, relatively quickly

i guess it´s just more noticeable up here, because its hotter, more load on the vehicle etc...


anyway, test drive didn´t happen today...

[bengerman]

thanks for your suggestions ynot,

radiator sides are sealed, shroud is complete, stone guard is fitted

will look into finding a 24v aftermarket temp gauge... makes sense


re your bonnet comments,
i know other gq owners who have tried lifting the back of the bonnet, in each of their cases, their vehicle ran hotter
reason we came up up with is that air over the top of the bonnet is at high pressure when it hits the windscreen creating an air dam preventing air from escaping from under the bonnet.
as opposed to the air at the front of the bonnet,
air hits the front of the car and gets deflected up, creating low pressure at the front of the bonnet

please feel free to pick holes through the theory :-)

[Alicetroll]

I have a similar problem in my 2.8 GU. I have recently cleaned the radiator, replaced the oil-cooler, thermostat, radiator and heater hoses (because of an oil cooler failure). At speeds over 100 kms the temp gauge heads up towards the top of the scale. it normally sits just below half.
does anyone else have this problem or a solution. (besides replacing the wiz-bang 2.8)

[Chops]

The Clutch Fans have a tendency to fail, especially in warmer climates. Its overlooked by many people, because as long as its spinning you don't even think of it. They are filled with oil, and one of the issues is the fan looks like its spinning fast, but when the engine revs, the clutch doesn't lock-up the fan, so the pulley spins faster, but the fan doesn't.

If you can spin the fan on the clutch rather easily, most likely your clutch fan is stuffed. In that case you only need to replace the clutch, not the fan itself.

[Adlarplant]

Ive had a problem with my td42 running warm from new in a 02gu and occasionally running hot steps ive taken so far raised the rear of the bonnet 5/8 of an inch (some help) removed lh sensor from radiator so ac doesnt cut out when it gets warm (theory is it keeps thermo fan working) some help replaced thermostats up and down the range (like a dog chasing its tail) little to no help removed spotlights and bullbar (driving at night was interesting) not much help to cooling replaced radiator with 4 core unit some help i finished up removing the water pump and checking it against another unit and found the impeller had worked its way aprox 3 mm up the shaft being an open backed pump it was therefore not pumping efficiently and causing cavitation since then i replace the water pump every 75000k or 6 months and ive had no more issues

[Alicetroll]

"If you can spin the fan on the clutch rather easily, most likely your clutch fan is stuffed. In that case you only need to replace the clutch, not the fan itself."

I can rotate the fan by hand. there does seem to be some resistance when the engine is cold. I haven't tried it while the engine is hot though. how much resistance should there be in the clutch?

[the ferret]

Mate, if the fan is working correctly, you will hear it roar when it kicks in.

[Alicetroll]

Mate, if the fan is working correctly, you will hear it roar when it kicks in.

Thanks ferret but my troll has a thermo-dynamic clutch on the radiator fan rather than a thermostat controlled electric one. As the fluid in the clutch gets hotter it gets thicker and transfers more torque to the fan so there is no roar the good thing with old tech is that it is eaiser to trouble-shoot.

[the ferret]

Nah, thats what I mean, your fan should make a roaring sound when the fluid does its job, have a look and see if there is any fluid leakage at the front of the fan hub, where the coil is.
It only holds a small amount, so any leak can affect it's operation. You can re fill some types, Toyota sell it cheers.

[Alicetroll]

Thanks Ferret. It seems that the fan in my troll has not been working for some time then as I don't recall it being all that loud. I went for a drive out to the airport today to get the car a bit warm and turned the fan over by hand when i got out there. It was as easy to turn with the engine hot as when it is cold. I'll have a closer look at it tomorrow.
Is there an after market mod to replace the clutch with a direct drive or electric fan? this one has failed before and cost the previous owner a new head.