OziExplorer replied:

Steve there is quite a range of different radiator cores available. Any proper radiator shop would be able to fit one of these higher efficiency cores, or even a core with more depth. In many cases you can fit a radiator quite easily from say a Holden or Ford V8 with very little modification, as it is easy to change the outlets on a radiator. These are often around a 1/3rd price of a Range Rover specific core. Find a helpful competent radiator repair shop, or better still try a few different ones and what they have to offer. If this is a problem on those vehicles, they may already have a proven fix.

Truckster replied:

How long have you had the car, or do you know its history?
Has anything ever been done to the cooling system?
Has the problem just started, or always been a problem?
Is it leaking at all?

Doesnt always mean its not getting enough air, could be worn water pump, or clutch fan gone, or just full of crap!

Theres lots of things to check before you go dishing out $400-800+ on a new Rad. Remember this model/style radiator worked well for years in Lots of Rangies... But now it could be 17yrs old(Doubt it thought!!).. Could be time to replace, but first check a few things.

Physically remove it from the car. Then hose the fins out, you can't get to the complete rad to hose it out while its on the car. I did mine on the weekend while doing a clutch fan, and the amount of crap that came out from behind the Cowl, and air cond cooler... I thought it was clean before that!

Next, turn upside down so the filler cap is on the ground... stick the hose in the bottom of the rad, so the water comes out the filler cap(which is at the ground level)

You could even while its out take it to a radiator place to get it checked for blockages inside.. My original one was 35% blocked inside... But Id try the other things first.

Other things you can do that are cheaper,
Check fan belt tension on the water pump.
New Coolant
Thermostat
Radiator Cap
Radiator hoses
Temp Guage Sender
Temp Guage!
You could change all these and keep the current ones as spares.


Not so Cheap are
Water Pump
Clutch Fan(if they have one)

All could be old, and just due for replacement.

As for where to get replacement radiator... ANY radiator shop. or you can get special Desert Racer style ones but then your lookin at $1500ish!

Another thing to do is, get one of the 4b magazines, and ring a few of the Rangie places that run ads in them. They could have upgraded rads in stock.

Where do you live??
I got mine for my GQ from Seaford Radiators in Seaford.. Ask for Sid.

Gary replied:

One thing that has not got a mention yet, is it an auto if so you may want to check the oil cooler lines from the rad to the oil cooler or Radiator as the case mybe.. If they have being hit by rocks and crimped in anyway then this will also give you a high temp reading without the engine actually overheating. It would mean the Rad just can not handle the extra heat coming from the trans. The lines dont need to be crimped by much.
Just another thing to think about.

Hope it helps.
Gary

Steve replied:

Further information on the setup:

Some Range Rovers have a problem with over-heating. This seems to happen when climbing long steep hills, especially in hot conditions, presumable meaning that the air-flow through the radiator is inadequate to allow proper cooling, even with the engine running at high revs.

The engine is new, has extractors, and extra bonnet vents, the
radiator is in excellent condition, and was recently replaced with a 3 core high-efficiency design to try to stop the overheating problem. The
thermostat is new (89 degrees), the gauges are calibrated and accurate. The viscous coupling on the fan has been locked up, there are two electric cooling fans in front of the radiator. They all work correctly, and are thermostatically controlled, not just from the air-conditioner circuit.

The cowling is fitted correctly, and the rubber seals between the condenser and the radiator are in place. The overheating only occurs at high engine loads when the vehicle is moving slowly (high revs, but low forced ventilation speeds)

The water pump is in good condition.

Darryn replied:

Steve fit an external engine oil cooler and if its an auto fit an external tranny cooler as well. I have seen various overheating vehicles helped by oil coolers and tranny coolers in the bottom radiator tank are one of the worst cheap and nasty things the auto industry does to save money.
Regd's Darryn

Eric replied:

Steve.
The first thing to check is the bottom radiator hose temperature. If the bottom hose is cold it tells you the radiator is cooling the water but the water is not circulating fast enough, if the bottom hose is to hot that means the water is circulating but the radiator is not cooling it enough.
There are some good pionts in previos posts but the one about kinks in the transmission oil lines is complete crap, blocked oil lines will cause transmission over heating only. Eric.

brian replied:

Hello Steve, i see everyone is focussing on cooling system,could it be minor leaking head gasket,or remotely possible to have porous cyl head,you said it was a new engine,if rebuilt did the heads need retensioning after initial running in period,just a thought.
if cooling system proves ok i would be looking for the source of the excess heat you seem to have.

brian replied:

Steve,forgot to ask did you have overheating with the first engine as well as the second??? is this why you have vents in bonnet??