GQ TD42 thermo fans not cooling well enough.....

[antpoo69]

I have removed the engine fan and fitted 2 x 16" thermo's to the back of the radiator running off a thermo switch. they cover a fair part of the radiator but currently have no shroud. it's not really cooling that well while driving.

i thought 2 fans would work a lot better than one engine fan but apparently thats not the case.

if anyone has any tips or ideas why it's not working as well as i'd hoped i'd like to hear them.

cheers

[ludacris]

Grab a set of au thermos and shrowed. I have tried other thermo fans and the au ones just kick arse over them for cooling.

Cris

[hokey]

what he said. i'm running ef fans on my mine (tb42) and it never overheats. the ef fans also have the dual speed thing aswell.

also running a ebay alloy radiator.

calvin

[marin]

Could always try fixing your cooling system if you are having issues instead of masking the problem.

[v8maverick]

EL or AU fans mate work a treat ive got the on 3 differant cars i would'nt use any thing else.

[antpoo69]

the car is not over heating. just gets a bit warm wen the aircon is running on a hot day and wen 4wdriving with the aircon on.

[chiefdog]

wondering why people need thermo fans? i run 6 inch lift 35's, put in a 3 core radiator and even up hills loaded, or crawling over rock in summer with ac on will sit under half. i ran thermo's on another diesel 4b and found on hot days they would run constantly. i understand that there would be small power gain removing viscous fan but i would rather my engine to maintain temp rather then getting hot then cool then hot then cool......Having said that i did install a thermo only as i had it lying around the shed doing nothing, i guess i am trying to say that a well sorted cooling system should work fine and yes the shroud would make a difference.

[antpoo69]

wat brand of 3 core radiator is it? and how much are they

[chiefdog]

honestly mate i am not sure. but any 3 core has 33% more coolant capacity than a 2 core. i also renewed stat, viscous fan, top and bottom hoses, quality coolant,keep your old hoses and stuff them in the guards at the rear as spares.

[durrie83]

Mate try not to re-invent the wheel here. Your patrol came out with a viscious coupling fan for a reason, they pull a hell of alot of air, better then most aftermarket thermos.

If your patrol's running warmer then it should why dont you just refit the factory fan?? If you must use thermos, like ludacris said, au falcon ones work well, I've also heard commodore electric fans work well too. Usually any OE electric fan will work better then an aftermarket!

Hope that helps.
Michael

[suggy126]

Thermos noramally run a hell of a lot better with a shroud too, especially at low speed, get your hands on one and fit it before replacing your thermos as well.

[mq_camo]

honestly mate i am not sure. but any 3 core has 33% more coolant capacity than a 2 core. i also renewed stat, viscous fan, top and bottom hoses, quality coolant,keep your old hoses and stuff them in the guards at the rear as spares.

not entirely true, if you have a 2 core that is thicker than a three core then the 2 core will be more efficient for cooling. just what i have been told anyway.

[Tommie]

Could always try fixing your cooling system if you are having issues instead of masking the problem.

I think he has replaced the engine fan with thermo fans to gain power.
Its a TD42 after all. I know the pain he's in

[ludacris]

AU thermos come with a shrowed.

Cris

[BeNoS]

there isnt much that will more more air than a correctly operating vics fan. and really the power gain is 2 parts of fark all when you consider your alt has to run pretty hard to run 2 hi power electric fan motors.
the only benefit i see with thermos is you can turn them off for water crossings but being a diesel water doesnt really affect them anyway.

[antpoo69]

i've got some au fans so im gunna get them on and give it a try. btw my car is not a standard disel. im running a bigger pump with 18 psi of boost and 180hp at the wheels with 35's. so it's working a bit harder than a standard TD42(non-intercooled).

i didn't remove the visciuos fan to gain power. i removed it to try to fix the cooling problem because i have a mate that has thermo's on his and it works great.

[gu town]

i've got some au fans so im gunna get them on and give it a try. btw my car is not a standard disel. im running a bigger pump with 18 psi of boost and 180hp at the wheels with 35's. so it's working a bit harder than a standard TD42(non-intercooled).

i didn't remove the visciuos fan to gain power. i removed it to try to fix the cooling problem because i have a mate that has thermo's on his and it works great.

i agree with the masking the problem comment.

tuning issue? there are plenty of high powered td42's around running standard cooling systems. there is a point, when you've done all that you can to the cooling system (radiator clean, new thermostat, good water, coolant and airflow) that you have to start looking at the very start of the problem(some one who knows more, feel free to shoot me down), whats making the extra heat..... tuning, or more specific your air/fuel ratio. with big power diesels, you gotta remember the A/F ratios are not much different than standard.

how long since you got it boosted up? did you do it yourself or in a diesel place?

[antpoo69]

i have problems with airflow cause i am running a warn hign mount with a cheezy bar. also have 2 x 240 blitzs lights on the bar. so that is causing problems with airflow but there is nothing i can do about that.

the pump was fitted by the guy that makes the pumps and then chapmans in cooroy did the dyno tune. it has been tuned like that for about 6 months but i had the overheating problem before that was done. so it's not a tuning issue. the problem is airflow, so by fitting the thermo's they will suck air a lot better wen running with a shroud.

im fitting the au fans today and i'll see how they go. if they don't work then i will have to then try to make airflow better or something like that

[antpoo69]

ok... so i fitted brand new au fans with shroud. im still having drama's with it getting a bit hot. is anyone else running these fans with a high mount winch. im guessing that because of the lack of airflow from the winch being in the way, it may be causing some drama's.

if anyone has some positive feedback for me as to other things that may make it run cooler that would be great.

[mike_nofx]

Have you tried removing the winch and spotties temporarily to see if that's the problem?

Also a a stupid idea, but is the fan running the correct way? I once bought a car with aftermarket thermo fitted by previous owner, wired incorrectly (blew not sucked) so it had cooling issues below 20kmh, above that the airflow was enough.

Worth double checking.

[toughnut]

i have problems with airflow cause i am running a warn hign mount with a cheezy bar. also have 2 x 240 blitzs lights on the bar. so that is causing problems with airflow but there is nothing i can do about that.

Thats not entirely true. There are a lot of things you can do to guide more air to your radiator. If you wan't better cooling for a small outlay then try some shrouding in front of your radiator as well. Waaaayyyyy to much air is lost around your radiator through all the gaps in your radiator support panel. If you shroud from your radiator to where your grill is you will get better results with your cooling.

I ran twin 16" spal fans on a very basic shroud and I also ran my boost a lot higher than factory for my comp truck. I had no issues with over heating. As antpoo said. Make sure they are mounted the way they were designed. Some are designed to push and some to pull the air through. So its not just a matter of having them spin the right way.

Over heating on a TD42 is an ongoing issue and there have been a lot of different ideas on how to fix it. Having the system flushed properly and then fitting the most efficient radiator/thermo fan combination is the most effective way to combat this. After that you need to look elswhere for the problem. Such as how you have you're engine tuned. Or possible even other methods of cooling like tapping into the cylinder head with an external coolant line which is a common mod now. Or if you have the space to run a second radiator on a tray or somewhere. I've even seen them under a wagon.

Oh. and something that is very commonly overlooked is the thermostat. You can get better versions that allow better flow.

[marin]

Is your radiator cap letting water out of and back into the engine when it gets warm?

Replace with a genuine, not just a supercheap special, and rule that out as well.

[toughnut]

Is your radiator cap letting water out of and back into the engine when it gets warm?

Replace with a genuine, not just a supercheap special, and rule that out as well.

Thanks marin. Forgot about that one. This can be a big issue. If it bleeds pressure too early then you'll lose too much water from your cooling system and air will build up and cause more pressure in the system and then lose more water etc. You can see what happens then. Also these are meant to be self bleeding systems but that isn't really the case. There is always trapped air around the termostat housing.

[antpoo69]

thanks for all info guys. that will give me a few more things to try. i'll report in once i've tried a few more ways to solve the issue.

i'll keep you posted

cheers

[ludacris]

ok... so i fitted brand new au fans with shroud. im still having drama's with it getting a bit hot. is anyone else running these fans with a high mount winch. im guessing that because of the lack of airflow from the winch being in the way, it may be causing some drama's.

if anyone has some positive feedback for me as to other things that may make it run cooler that would be great.

There are plenty of comp trucks with highmounts and spotties running big boosted diesels that are not getting hot. How old is the radiator. Is the water pump working, thermostat, tune might be out.

Grab a new thermostat and radiator cap. Order a new water pump gasket and remove it to check if it is still any good (simple job). Buy a new radiator and get another reputable tuner to check the tune on a dyno.

Cris