Your electric fans should come on when the engine is getting hot, especially in stop and go traffic as well as when the a/c is turned on.
When cold, the fan will spin a little with little resistance, when hot and the engine off, there should be a lot of resistance when trying to spin the fan.

 

Update: My fan clutch was gone. I changed it but I was still getting slow reaction. I took the old thermostat out and put it in hot water with a new thermostat. The new one quickly started to open at 88C as designed. The old one just started opening a few degrees higher and never fully opened. Installed the new thermostat , filled the system with fresh coolant and I was back in business.

The fan definitely generates more noise with the new clutch.

The best part of it was the puzzled look on my wife's face when she saw me in the kitchen boiling some car parts with a candy thermometer while describing what I was doing to someone on the phone.

 

I just started experiencing abnormal temps. I have the ultra gauge and noticed yesterday that it was getting up to 220 range in stop/go traffic. Since I've owned it, it's been 197 on the freeway and 203 to 206 in stop/go traffic.

When you speak of the fan clutch, are you just talking about the circular fan and as in the blades are broke? I've searched around and can't find any other articles on this. The T-stat is only about 1 year old also and had a flush and fill when the new T-stat went in.

 

There are many many threads about Rovers and high temperatures. But what I think you're asking is whether the fan and its clutch are one and the same. They are not. There is a viscous clutch bolted to the front of the engine that turns the fan. It spins slower at highway speeds, since there is plenty of air being forced through the front of the vehicle by its own forward motion.
When this clutch fails, it either seizes up, causing the fan to spin constantly, or it will spin in "neutral," barely moving the fan at all. Try to spin it by hand, with the engine off of course. It should turn, but with some resistance. (It has been variously described as "feeling like it's full of peanut butter.") You also have two electric fans behind the grille that should turn on automatically when the AC is on, or when the engine temp reaches 212 degrees Fahrenheit.

 

Thanks for the reply Mike,

I forgot to mention that yesterday I checked the coolant level and it was a bit low. I topped it off and this is the second time in a period of 6 months I've had to top it off. I will be doing a pressure check on the system to see where the leak is and will probably have a flow test done on the rad.

I took it out again this morning and the temp was acting a bit more normal. An honest 197.6 at highway speeds and hovering around 203 when idle. I let it sit for 5 minutes in the drive and it stuck at around 210. This wasn't the case yesterday when it was hitting 220 city driving (30-40mph).

I'll peel off the cover plate and do the hand spin test on the fan to see if it's as you described. I wanted to diagnose this as I'm ordering some fill plugs for the differentials (swapping out fluids in them and transfer case) and if I had this fan clutch to replace, thought I'd order it up also.

 

You're welcome! A few other things to think about: there could be some air trapped in the system. There were a few threads about "burping" the air out. If your water pump has seen 60-80k miles, it might be time to replace that as well. (The clutch and water pump tend to fail around the same time.) Depending on your mileage it may also be time for another flush-n-fill. Better to get this under control while you have a few months of cold, A/C-less weather.

 

I burned this comment into my memory when I got my D1 and never had to do anything with the info because the hottest mine seems to get is about 204F on a 90 degree day idling in town.

Just took it on a trip over Imogene pass in Colorado though and got pretty deep into the danger zone. I was so focused on the road I didn’t notice it hitting 220 so I was late to get the heater turned to full blast. In the 50 yards it took me to get to a pull-off, it had hit 238. Turned it off and saw the ultra gauge peak at 240 (with the engine off). Popped the hood to let the cool mountain air cool it off, poured some water on the block, added some coolant, and gave it a half hour. By the time I restarted it was down to 170 and stayed under 190 the rest of the drive with the heater on max.

So in Spike’s words, I’m “Lucky”. Should I leave it at that and just aim to never get in this situation again, or should I be worried that I caused the engine some damage in those last few minutes? Anything I ought to double check?

 

I ran my D1 up to 11,000 feet today - ran the a/c the entire time and it never went above 180

 

what was the ambient temp outside? It was about 70 and sunny at the time for us. I’d also frankly been driving kind of fast for how steep it was. Still, it’d be nice if I didn’t need to run the heater for moderate off-roading like this. Coolant levels were fine, recently recored radiator, fan was working, as far as I know the cooling system is fine..

 

The block and heads can expand and warp when overheated. Running the cooling system unpressurized, with expansion tank cap loose, is a way to prevent this issue, and minimize leaks. There are several threads about this and a very good technical analysis by Extinct. Works great with 50/50 coolant mix. There might be an issue with high elevations, though, so maybe need a 60/40 mix.

I run both my trucks this way, over 100 deg F today outside. When I replaced an expansion tank recently so I can see the level from the outside, it came with a nylon plug, not a cap. I modified the plug with a small vent fitting and a rubber tube and that has prevented the small bit of leakage I was getting from the loose cap by itself when the tank is at the full mark.

Pay close attention to coolant level and usage. No leakage, no harm, no foul. If you want to check something, check cylinder compression against your baseline values. If things warped enough to affect head gasket sealing, there could be a change in compression values.