TB42 Cooling System

[GQGasPig]

Hi All,

I know it has been done to death but I am not a mechanical genius.

I have a dual fuel 4.2 GQ that on idle with air con on during a hot day will creep to 3/4's on the temp guage. When I start driving again the temp drops back to about half which appears to be the norm temp.

I had a new rad put 18 mths ago together with a new thermostat and hoses.

Is this normal? If not, why not and what do I need to do to fix it (besides not sitting at idle for too long)?

Cheers
MS

[viperguy]

mine does the same.. runs a bit warmer with air on.. new core in radiator etc.. sounds pretty normal to me.. it shouldnt get higher than 3/4 and will fall when driving. mine even climbs when i boot it or driving a long up hill.. but will just get to 3/4 and settle..

[ludacris]

Mine sticks to about a third and climbs a little bit when I give it a bit but 3/4 is a bit to much I think, Check that your fan is working. Both of them that is.

LudaCris

[planb]

mine does the same.. runs a bit warmer with air on.. new core in radiator etc.. sounds pretty normal to me.. it shouldnt get higher than 3/4 and will fall when driving. mine even climbs when i boot it or driving a long up hill.. but will just get to 3/4 and settle..

ditto

doesnt get beyond 3/4 but i think that it shouldnt rise beyond half.

i recently flushed the system thoroughly, replaced the water pump and filled it with coolant.

the mechanical fan and clutch ass. works fine (allthough, there are some major cracks in the plastic fan hub area, waiting for it to break) pull still pulls hard.

electric fans run sweet and there is no thermostat

it is definately worse with the ac on, but will climb on long hills.

ive lived with it, but am considering fitting twin au fans. this really shouldnt be necessary though.

me, im pissed

[hottiemonster]

mine normally runs at half way or a tiny bit less.

with air con on, it runs a little hotter

back in the day when i didnt clean my radiator, it used to reach the first Hot line when four wheel driving, and this was on a cold night!!!!

after cleaning the radiator, it hardly changes offroad and just stays at the same level

[Draven]

Erm...well mine gets to a little bit before halfway...and doesnt move..even with air on...

The only time ive seen the temp guage move was in 'very' soft sand, with a 'very' big load. (read 60ltrs gas - 70km)

[Dirty Dave]

is your thermo fan on your a/c working???
and is your clutch fan working properly??
running coolant?? being an alloy head and all??

[planb]

is your thermo fan on your a/c working???
and is your clutch fan working properly??
running coolant?? being an alloy head and all??

the thermo on the ac is working

havn't really looked to closely yet, correct me if im wrong

but im thinking there might be a cooler for the auto up front also. if there is, i might think about moving this to improve the air flow

[Rainbow Warrior]

As long as you're not losing water too, the temperature rising was the first sign of the No6 cooling jacket corroding into the cylinder on my last motor.

[bazzle]

Yes on some they do run up to 3/4.
You must run a Thermostat
Ensure rad fins are clean (remove to clean. NOT just hosed thru on car)
Use 30 to 50% coolant
Ensure clutch fan working (should spin up when you start in morning and drop out within a few minutes)

Temp gauges on these also optimistic

Bazzle

[Phill]

I got rid of the thermo and it ran better but the best thing to do is to change your head gasket and add red line water weter to your radiator

[Bartso]

mine use to sit on about one quarter all the time off road on road sitting in traffic then one day it started to rise it turned out to be no6 water jacket it corroded away a little bit

[Gutless]

is your thermo fan on your a/c working???
and is your clutch fan working properly??
running coolant?? being an alloy head and all??

the thermo on the ac is working

havn't really looked to closely yet, correct me if im wrong

but im thinking there might be a cooler for the auto up front also. if there is, i might think about moving this to improve the air flow

There is a cooler. It runs thru the radiator tanks

I just had my radiator rodded ( cleaned) and did the new hoses thing withcoolants etc.

I also fitted a LARGE oil cooler for the auto, and have just left the factory one disconnected.

I had a temp gauge on the auto before the work was done, and it frequently went over 100 degrees. Since fitting an indipendant cooler, it will stay at 50 all day, and when its being reved/ steep hills etc, it may climb as far as 70

Worth the $150 bucks for a cooler in my opinion.

Pete

[planb]

is your thermo fan on your a/c working???
and is your clutch fan working properly??
running coolant?? being an alloy head and all??

the thermo on the ac is working

havn't really looked to closely yet, correct me if im wrong

but im thinking there might be a cooler for the auto up front also. if there is, i might think about moving this to improve the air flow

There is a cooler. It runs thru the radiator tanks

I just had my radiator rodded ( cleaned) and did the new hoses thing withcoolants etc.

I also fitted a LARGE oil cooler for the auto, and have just left the factory one disconnected.

I had a temp gauge on the auto before the work was done, and it frequently went over 100 degrees. Since fitting an indipendant cooler, it will stay at 50 all day, and when its being reved/ steep hills etc, it may climb as far as 70

Worth the $150 bucks for a cooler in my opinion.

Pete

nice

thanks for the tip

ive bought a bigass bmw cooler before for $70 new

might just have to get me another one.

where did you mount the oil cooler ?

against the rad ?

[Gutless]

Its infront of the radiator. It basically covers the side of the radiator that the fan isn't on. I used some spacers to keep the cooler off the radiator. It fit pretty neat too. I will try and get some pics, but i'm not gonna take the bullbar off again to get the grille off, so I can take a proper pic

Just take some measurements of the area behind the grille and chuck the largest one you can fit in there.

[planb]

cool, thanks dude, lets hope it helps keep the heat down a bit

[MEX]

Gutless,

Can you tell me the brand & model number of the cooler you fitted. Also what effect has the installation of the cooler in front of the radiator had on your engine temp?

MEX

[Gutless]

MEX.

I'll have to wait till monday to get you those details, cos the packaging is at the work shop.

As for negative effects on engine temp, there has actually been a slight drop in temp. I think its cos the radiator is no longer having to cool the engine, and the auto.

I spaced the cooler about 10mm off the front of the radiator, so air flows thru the middle ( not much, but it all helps). The auto used to reach about 100degrees during a drive to work, but now it barely goes over 50! So when you look at it that way, the air that passes thru the oil cooler, and into the radiator, is actually colder ( by 50 deg) than the oil that would have passed thru the cooler in the radiator on the original setup. I was thinking of fitting a small thermo fan to it also ( I did this on the auto cooler on the zook. It made a big difference. But the cooler on the zook is mounted behind the ute cab, not up front), but I don't think I need it now.

Pete