Hi everyone. I have a 2003 disco with about 224km on it. I’ve got a head scratcher with my coolant temp. My scan gauge reads it at 215-220 on any trips longer than 20 min. It rises and falls + - 10-15 when going up a hill or down a hill. Replaced the thermostat with a 185f OEM. Doesn’t have any impact. My mechanic suggested a new clutch fan so replaced that but the temp is still high for my liking…or is that normal? I’m not mechanically sound so bare that in mind. Any thoughts how to get it lower? Water pump?

mike

 

Hello Mike. I see this is your first post here. Welcome to the forum! You’ve found the best online source for information and support for you to maintain your DII.

First, do you have a copy of the RAVE Workshop Manual for the Discovery Series II? If not, you can download a free PDF from the link in my signature below. It’s an invaluable resource.

Once the thermostat is fully open it has no further impact on temps. And the fan clutch plays a role only when the truck is stopped or moving in slow traffic. Presuming the water pump is moving coolant through the system, temps are dependent on the efficiency of the radiator.

The auxiliary fan kicks in at 212°F, so your truck's temps are high, but not (yet) dangerously so. I recommend replacing the radiator.

 

If the temp is rising 15* above your normal 220, that’s getting almost to the point that you’ll be damaging your engine. Yes, your radiator may be the problem, but your new t-stat could also be the issue.

 

You could bench test the thermostat to confirm whether or not it is working properly. Remove it from the truck and drop it into a pot of water on your stove. Use a thermometer to observe the temp at which the thermostat is opened fully.

 

@Hegarty13 please define hill,what are you are seeing is pretty normal for the part of British Columbia I am in, but the grades are 6 to 12%. I am running the inline Thermostat and a 170 on the hiway run at about 65 mph I will go from 174 to 188 in cool temps 60F ,dropping as low as 164 coasting down the other side.

 

Suggest you read this thread: https://landroverforums.com/forum/di...thread-105010/

 

Suggest you read this: https://landroverforums.com/forum/di...thread-105010/

 

After reading the last two post, which l found to be eerily similar...lol, l'll second that this is a nice upgrade. Temps in my 04 became much more manageable, 187 was the highest l ever saw after swapping stats. Before that, it would creep up to 220 sometimes during prolonged idle (with A/C on or ambient temp above 85). I'd changed fan and rad, with no change. The location change alone...is worth the swap.

 

Sorry about the double post, was on Starlink and the internet was spotty, it must have doubled somehow.

 

No biggy, actually, been seeing more of this lately for some reason.