This must be the 1,000th post about this. Cooling system running at 200-210 degrees even when outside temp is below freezing. Seems to get hotter going down the highway.

No coolant leaks, 180 degree thermostat and all new hoses, etc

About 120k miles on the truck. Thinking the radiator is full of crap. Are metal radiators worth it or just keep it stock?

 

Just grab an OEM style replacement off of Ebay for less than 100.00 and call it a day.

 

Its not the radiator. Since you are driving down the highway when its cold, the fluid in the radiator gets very cold and the thermostat wont be open much at all to keep the engine cool. The external thermostat is a bad design if you want the engine running in a tight tolerance of temperature since the cold air will cool the hoses and the housing which creates a larger temperature difference compared to an engine mounted thermostat.

Just set the ultragauge alarm at 215 and dont worry about it.

But yeah there probably is junk in the radiator but it wont have much effect when its near freezing outside. What are your temps like in the summer? Sitting at idle should be around 200 and stopping after a highway run might hit 210. Just driving around should be in the 190s.

 

Agreed. I have higher temps in winter than in 90 degree summer heat. The thermostat stays closed more due to the cold air. At a stop, the temp rises before the thermostat can open effectively. Anything under 210 is absolutely fine.

 

Yep this is what imI experiencing as well. Thought about insulating it

 

we did a long off road trip yesterday and my ultra gauge showed 212 to 220 all day long, I was alarmed and scared but the intake was cool enough to keep hand rested on it. it was mid 40's all day long. I really do think theres a problem. I replaced the radiator, thermostat and all hoses a few years ago. temps just don't add up!

 

I know they run hot. Land Rover cooling system is a dinosaur . Just garbage. I was hoping with the new thermostat and fixing the cooling leaks I'd see better results. This is my first 4.6. I also drive like a jackass and the wife isn't much better with it.

Just for kicks I'm going to pull the radiator and see if I have sludge in there with the camera on a stick. Paid snap on enough for it, might as well use it.

Also don't run ultra guage cause I live dangerously.

 

 

 

This is interesting, I've never heard of this problem.
Makes sense though since the thermostat housing is out in the open.
Insulating the thermostat sounds like a good idea for cold weather, and maybe warm weather too??
Maybe, maybe, having the thermostat housing insulated would cause the truck to run a couple degrees cooler in warm weather, assuming the insulation works as it should and lets it open sooner??
Hoping someone can try this out with a temperature gun and/or an Ultra-Gage, in warm and cold weather.
I would...but mine is still broken, lol.