Overheating problems..

[DiscoJW]

I just recently purchased an 02 Disco with 55k miles on it. I've had it two days and it has overheated both days. I have added a lot of coolant after running it. I consulted with the local dealership about what's going on, they said that Rovers are notorious for trapping air inside the cooling system and engine, and it may just be their way of getting the air out. I also asked if there was a bleeder valve I should open when I add coolant, the service guy told me there is a valve on the main hose which I've found, but didn't say anything about opening it while adding coolant. After everytime I drive it the coolant level has gone down a good bit, and it isn't leaking but a few drops.

So, I guess my question is, does anyone know what this sounds like? How do I add coolant, do I keep the engine running and open the valve while adding coolant? I had a Jaguar and it did the exact same thing, only I didn't know that there was a bleeder valve and I ended up causing the problem by building too much pressure throughout the system. I don't want to make the same mistake twice. Thanks

[auwesman]

It might be air in the system....it might not.
The best way to find out is to open the bleeder valve, unclip the filler tank and lift it as high as you can. Pour coolant until you get a small amount of coolant flowing out of the bleeder valve. Retighten valve, clip fill tank in place, turn rover on and turn heater on full blast. If you get HOT heat after a min, then you should be good.

It could be a few other things (blocked radiator/bad radiator for example). Overheating the engine will cause all sorts of trouble, so you need to figure this problem out before you start driving it around. A slipped sleeve will wind up costing some serious $$$.

Do a search for overheating, you should be able to find quite a few threads.

[DiscoJW]

Thanks, I did a search and found some useful info.

Also, I checked the overfill bottle, which was full, turned on the Rover this morning and turned the heater to full hot. It blew cold for about 15 minutes and then it started to warm up. DiscoMike told me to attempt to cycle the system by revving the engine up to 1800 RPMs and letting off. The Rover never got above halfway on the temp gauge, but I haven't driven it at all today. I'm about to go check the coolant level again and maybe do the same thing over again, revving the engine up and down with the heat full hot.