Land Rover Repair: 2001 4.6 motor overheating, radiator cap, cylinder sleeves

Question
John,
My Range Rover is overheating and spewing water out of the reservoir.  My first thought was a thermostat problem, but it seems if hot water is getting to that point, it must be opening. Is it likely that even though it is not leaking, my water pump is bad?  Since there is no radiator cap I can't simply look in and see the circulation.

Answer
Hi Ron,

obviously your coolant is boiling over.  Thermostat could be sealed closed and the remaining coolant is boiling off.  One way to check is when the engine is first started (not so hot) and you feel the temp on the upper and lower rad hoses.  If the thermostat is open, both hoses would be same temp (approx). If the closed, one hose will super heat quickly while the other remains cold.

Could also be blocked rad.  Water pump, rare but it does fail.  You may want to have a local rad shop pressure test the system.

I'd go with thermostat (when was the last time it was replaced?  Ever?)  Its not expensive, if you do it yourself, and worth the effort considering the damage that an overheated LR engine would cost you.  BE AWARE...extensive overheated engine could cause cylinder sleeves to drop (welds crack or break) and this renders the engine useless. $$$$

Best of luck,

JohnMc

Followup:

Hi Ron,

thanks for the kind comments.  If you need to the tech sheets for either the thermostat replacement or water pump, just send me an email and I'll reply with the documents.

Regards,

JohnMc
jmcinnis64@hotmail.com