Overheating Engine

[cas-gord]

We have 2002 gu 4.2 turbo diesel, overheats when going up big hill towing 3 ton caravan been doing it since new, would an intercooler or oil cooler solve problem?

[patch697]

Both will help but not necessarily fix it.

One of our Moderators on here is a mechanical GURU. He may have some good advice for you here.

[YNOT]

The fact that the car has been struggling to keep it's cool since new indicates that there is probably not actually a fault with the car, just that towing a 3 tonne van up a big hill puts a massive strain on the cooling system. You probably figured that out already!

What to do about it?

First you need to maximize the airflow through the radiator. If you have big spotlights either remove them or fit smaller lights. Make sure the radiator is sealed around the edges with foam tape so that all the air entering the front of the car is forced through the radiator. If you have a fly screen type bug screen across the front of the car, remove it. Regularly check the radiator and A/C condensor fins for debris build up.
You should probably also consider fitting an upgraded aluminium intercooler like the ones PWR sell. (www.pwr.com.au)

Next is engine tuning. You can go two ways here, either get it dyno tuned to ensure pump timing, boost and fuel delivery are properly set to factory settings, or go for a higher state of tune. Obvoiusly this option will cost a bit more. There are several companies (MTQ turbo's is one) that can rebuild your turbo with larger compressor and turbine wheels which are a lot more efficient and will result in a much cooler air charge at the same or higher boost levels. Combine the high flow turbo with a bigger exhaust (including the dump pipe off the back of the turbo, very important) and a full dyno tune and the engine will have a lot more power and torque (up to about 30% more) meaning you won't need to work the car as hard to get that big van up the hills.

Intercooling will help as well, but look for a well designed top mount intercooler and a large scoop. I suggest top mount over front mount as a front mount will add more heat to the air entering the radiator as well as adding a restriction to the air flow. Check www.are.com.au, those guys know more than most about the subject and have done a fair bit of research into scoop design as well.

An oil cooler may help a little as well, but finding a location where it does not interfere with radiator air flow might be a challenge.

Tony

[AB]

I'll move this thread here mate so others can see it better.

[MQ MAD]

So youve had the car since new and your persurveering with a heating problem this long ???
This problem should have been fixed long ago,seen the price to repair these motors
Anyway the usual problems with heating issues is blocked radiators youll be surprised what the impact of this will do
After owning this long ,it would be something near first to do
Get the radiator rodded,about $100 ish (you remove and replace)
Then go from there
My GQ (under 200K when bought) had a heating issue within 2 weeks of purchase
It was a blocked radiator
Your car being 8 year old there would no doubt be a few things in the cooling system that would need replacing by now
Hows the clutch fan hub,plastic fan have any cracks ect ect

[gibbon]

mate i put a tefba filter in its a i line filter for top radiator hose(there on line) n it picked up heaps of shit n my temp came down a bit
they r gold put em on all my cars now

[Macgyver]

My sons GQ 1991 Gq Patrol overheats on the highway about an Hour after running at 2200 rpm. Checked everything including head, new radiator, thermostat, radiator cap, water pump. Just found a vacuum leak near the carby hope this fixes it. It is dual fuel LPG/Petrol and overheats on both. Just keeps pumping out coolant into overflow bottle and then boiling. Weird one!!!

[Bigrig]

My sons GQ 1991 Gq Patrol overheats on the highway about an Hour after running at 2200 rpm. Checked everything including head, new radiator, thermostat, radiator cap, water pump. Just found a vacuum leak near the carby hope this fixes it. It is dual fuel LPG/Petrol and overheats on both. Just keeps pumping out coolant into overflow bottle and then boiling. Weird one!!!

Just replaced the radiator in my 92 GQ to an all alloy unit - overheated at the slighest of hills and pretty much ran (highway driving) at about two thirds on the indicator - new radiator, cooling system flush, and colder thermostat then SHAZAM!!! Runs at about one third on the indicator, doesn't have any bother with hills etc, and I have the Nissan badge and 4 spotties lined up in front of it ... it still heats up a bit if pushing it out on the tracks, and especially on LPG (runs hotter anyway I believe) but other than this, I am still looking into (help Tony!!!!) getting an intercooler for the gearbox as it just seems to run blistering hot (auto, but I can feel the heat off the console in the car to the point it burns my leg!!)

[YNOT]

Scott, there is too much air getting to your radiator, you should fit a high mount winch up the front to block some more air flow!

Intercoolers are for cooling air heated by turbo or superchargers, you need an oil cooler to cool oil!

Tony

[Sir Roofy]

maybe the cooler is to small for the auto or you got no
oil in the trans

roofy