I just replaced the water pump in my 97 Disco I and found that the radiator now needs to be replaced because it still overheats when going up hills.
I have the bible for the Disco I and will attempt to replace it myself.

My question is, in the procedure to put everything back, it asked to "lubricate new 'O' rings before fitting. What are these new 'O' rings that have to be lubricated and with what lubricant are we talking about?

chrisusvi

 

The radiator does not use O'rings. The AT fluid and engine oil coolers do use them on the alum. pipe connections. However, youcan replace the radiator without disconnection those, as they can be moved out of the way (towards the engine) to clear radiator replacement.

 

Read your post on LRO.
I suggested that you replace the t/stat and verify you got all the air out of the engine prior to looking at the radiator, also have a radiator shop room a flow test on the radiator, you may just need to have it cleaned out.
Mike

 

Another thing to look at is the viscous unit on the fan clutch. The fan might not be spinning enough. That's what happened to me last summer...

 

Had a similar prob on a 96 dI, turned out to be the electric fans were inop. I got 2 used ones from roverlandparts.com for cheap, never had another prob.
(well until a suburban pulled out in front of me on the highway)