I have a 99' Disco II that alledgedly has had the heads done, 40K miles ago and is now starting to overheat at about 15 minutes on the road. If you reduce speed dramatically it will return to normal but if you hit a small hill or place demand on the motor it shoots right back up. There is no oil in the water, there is moisture coming out of the tail pipes on startup, I've replaced the fan clutch that was bad, fan shroud thats was shreaded put in a new radiator, thermostat, all the hoses while I was at it...and still the same issue.
One of the comments on the forum was possible sleeve issue?? I know the 97's and 98' had that issue but not so on the 99's. Is it possible that the old owner never really did the heads right? or? Any suggestions?

HELP

 

I had the exact problem and went through every concievable solution and I wound up with a dropped sleeve,,,,,It is possible that if they didnt tighten correctly or used the old head bolts,,but usually with heads you get the moisture in the cylinder, and the smell...most likely you are in my club,,,,,

James
1999 Disco II
66 F-100

 

There are a number of reasons for the overheat. I would be glad to walk you thru all that needs to be checked and in the mean time don't drive it or you will toast the engine.
PM me your number and I'll call today.

 

I would listen for the water fall sound in the heater core.
If you have that - then could be air in the system from a bad head gasket.

You can try to take the coolant cap off of the expansion tank and see if it pushes coolant out.

That is also a sign of pressure in the coolant system.

My 2001 pushed out coolant and had the water fall sound.
Once head gaskets replaced - no coolant would come out when I had the cap off for 10 minutes or so.
No water fall sound.

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One more thing I would do:
Pull off the black rad cover and try to reverse flush the dirt and debris from all the radiators - the regular radiator and the A/C condenser.

Lots of dirt in these can make the Rover heat up when you are driving on a hot day.
I had a BMW that did this
When I was replacing the radiator with a new one - I saw the radiator had
a lot of crud in it.
Hosed it out.
Ended up taking the new radiator back and getting a refund.
As the old radiator cleaned up just fine.