Almost overheated my Disco. I was at a traffic light in town when I see a guy next to me yelling and pointing at the front of my Disco. I rolled down the window and he says I'm leaking coolant. I look at the temp gauge and it's at the high side of normal, just below the line but not in the red zone. I pulled over to look at it and saw the expansion tank had cracked along the seam and was spraying all over. Lucky me I keep a gallon of coolant in the back. I just kept the cap loose so it wouldn't build up pressure and drove home. Ordered up a new one from AB and they tell me that the tank is a common fail item... I didn't know they were.. unless I overlooked a posting about it on this forum. Learn something new about these Disco's all the time. So if you're a Disco 1 owner and haven't replaced your factory expansion tank, you might want to get a new one... cheaper than burning up the engine.

Eric

 

So, do you actually know what has failed??? Go look and see, it may not be the cap or bottle but a head gasket. In the mean time don't drive it.

 

The seam on the tank had cracked... don't know how or why, but it cracked. folks at AB said that was typical and said I should also get a new cap, which I did.

Eric

 

So, do you have the new parts, do you know how to bleed the coolant system and do you have plenty of 50/50 Dexcool and a bottle of Water Wetter ready to go?

 

He has already said that he ordered a new one Mike.
DI's do not use DexCool.
http://sancarlosradiator.com/dex-cool.htm
In fact nothing should use DexCool.
http://sancarlosradiator.com/dex-cool_pics.htm
DexCool is the reason DII's have so many cooling parts problems.

 

I learned this as well in fact just an addition to this thread (from my understanding as explained to me) the black reservoirs are the OEM originals that are prone to cracking, they have either modified them or another company now makes them or something but they are now white and they are the good ones, I think one of the guys at atlantic british explained this to me.

 

New tank and cap installed. The new tank definitely seems thicker than the stock. Anyhow, took it for a 60 mile drive and no problems.... for now.

Eric