Ditto what best 4x4 said

 

Do not take the cap off on cooling system that is 221 deg. The reduction in pressure will cause some of the coolant to flash to steam.

You can get rent a coolant system pressure tester. Start the engine cold with no pressure indicated on the gauge. The pressure a the cooling system typically builds to approx 7 lbs at normal running temps. If the pressure builds quickly to around 15 lbs the pressure is coming from one of the cylinders through the liner or head gasket.

 

If it's just at idle, but goes down into the 190s when moving, I would suspect fans. At 221 is your A/C condenser fan running? It should be. Also, I'd replace the fan clutch, even if it seems OK. The only difference between idle and driving is the volume of air and coolant flowing.

I suppose it could be the radiator too.

 

To many people throw parts at rovers.

It's air.

You can test your fan clutch. Test it.

You can see coolant flow...means the water pump is good. It's not rocket science.

Old fiat spiders had the same setup, their procedure was to raise the front of the car...it also works with a rover.

 

Actually to many people don't throw the correct parts at their rovers IMHO.

Especially replacing old worn out/clogged radiators, or thermostats. I can't tell you how many times I've heard or seen people dump $$$$ into a head gasket job, and they didn't replace the actual cause of the issue in the first place. Be it a stuck thermostat, clogged radiator, worn fan clutch, bad efan, water pump, bad coolant hose, or even the lack of coolant. Then they start driving it like it's 100% new and BOOM it blows up again they b!tch and complain how LR's suck, and it ends up on CL with a good body, and blown motor.

LR D2/P38's are harder than some cars to bleed out the air, but it will eventually bleed the air out thru the coolant jug with several hot/cold cycles. You can tell once you get the air out if your temps level out vs spike up/down. If it levels out, but it's warmer than you'd like that's when you start checking things like the radiator, fan clutch, and efan.