Reasons why your 4x4 is Overheating

[simongnz]

My GQ started overheating for the first time on the weekend. I was wringing its neck uphill with a trailer on but certainly not for the first time. The only difference from normal is that I had the injectors replaced and the valve gear refaced. It's got a lot more power now and no smoke. Could the overheating be a result of the increase in power? It was pretty gutless and smokey before but never overheated.

[YNOT]

It's likely your cooling system was on the limit before due to gradual degradation over time, and now that the engine is working to it's full potential again the cooling system can't cope. Time for a cooling system overhaul (new radiator, thermostat, hoses, coolant etc) to get the system back to full cooling capacity. Consider upgrading to a heavy duty 3 core radiator.

Also look at what is in front of the radiator, ie big spot lights, which solenoid packs etc, they can have a big effect on the amount of air getting to the radiator.

Tony

[simongnz]

Thanks Tony. More money! I might start with the coolant as that's looking pretty average at present.

[katwoman]

I am about embark on changing the 5 core aluminium radiator and thermo fans all back to standard.Any tips on what to do or NOT to do.. Have priced new radiator, clutch fan and hoses. Having trouble getting blades. ( new or 2nd hand.) Katrol went to docs yesterday, and they would not touch radiator cos it doesnt come apart. These aluminium rads are not recommened for GU's apparently. Or should I get 2nd opinion? Just spent $1500 on new boots, now gotta find lots more $ to put back to original.

[Bigrig]

I am about embark on changing the 5 core aluminium radiator and thermo fans all back to standard.Any tips on what to do or NOT to do.. Have priced new radiator, clutch fan and hoses. Having trouble getting blades. ( new or 2nd hand.) Katrol went to docs yesterday, and they would not touch radiator cos it doesnt come apart. These aluminium rads are not recommened for GU's apparently. Or should I get 2nd opinion? Just spent $1500 on new boots, now gotta find lots more $ to put back to original.

What's wring with the radiator??? Been flushed??? If it has no leaks etc (pressure test), then I don't see the reason for changing an expensive item - I have one, and it's a bottler. Has the cooling system had a proper flush (under pressure)?

Have you tried running a colder thermostat also? I did this in conjunction with the radiator and mine barely ever gets to half way now under load, let alone living above half whilst normal driving previously.

I'd be getting a second opinion just on the off chance you could save yourself some spondoolies!

[katwoman]

What's wring with the radiator??? Been flushed??? If it has no leaks etc (pressure test), then I don't see the reason for changing an expensive item - I have one, and it's a bottler. Has the cooling system had a proper flush (under pressure)?

Have you tried running a colder thermostat also? I did this in conjunction with the radiator and mine barely ever gets to half way now under load, let alone living above half whilst normal driving previously.

I'd be getting a second opinion just on the off chance you could save yourself some spondoolies!

have thought of all that. The radiator man wouldnt touch it !! Will do it myself first and as u say, change thermostat and see what happens. There's no leaks, it just runs too hot. Operating temp of GU is 82c. Katrol runs at 90c. Under load she runs at 100-110c. THX for that. The radiator, I'm told is not that old. ( maybe 12 months) and apparently there is a secondary thermo missing off it. Maybe 2nd thermo will help. Just thought it would be easier to go back to standard..

[Bigrig]

have thought of all that. The radiator man wouldnt touch it !! Will do it myself first and as u say, change thermostat and see what happens. There's no leaks, it just runs too hot. Operating temp of GU is 82c. Katrol runs at 90c. Under load she runs at 100-110c. THX for that. The radiator, I'm told is not that old. ( maybe 12 months) and apparently there is a secondary thermo missing off it. Maybe 2nd thermo will help. Just thought it would be easier to go back to standard..

Mate, the aluminum radiators run cooler than the stock units by a long shot, and if it's only 12 months old, I'd be keeping it for sure (they are nearly double the price for a reason). Definitely get it flushed professionally under pressure (they use a steam attachment I believe and high pressure to blow every bit of crap out of the system. Throw a cold thermostat in it and see how it runs. Cold thermostats open about 12 degrees cooler than standard (around 75 degrees I believe) and should definitely make an improvement.

Good luck with it mate!

[katwoman]

Mate, the aluminum radiators run cooler than the stock units by a long shot, and if it's only 12 months old, I'd be keeping it for sure (they are nearly double the price for a reason). Definitely get it flushed professionally under pressure (they use a steam attachment I believe and high pressure to blow every bit of crap out of the system. Throw a cold thermostat in it and see how it runs. Cold thermostats open about 12 degrees cooler than standard (around 75 degrees I believe) and should definitely make an improvement.

Good luck with it mate!

Well, just had second opinion, and looks like I'm goin back 2 original. Damn it

[blair]

i think my thermostat could be stuffed the temp gauge take ages to climb to quarter way up guage

[YNOT]

i think my thermostat could be stuffed the temp gauge take ages to climb to quarter way up guage

Sounds like it's stuck open.

Tony