Disco 96 Overheating

[SNorero]

Hi everybody! My old Disco has been with me for 10 years, and commercially speaking it has almost no value, but I want to keep it and use it from time to time. Unfortunately it started overheating, so I did all of recommendation I have found: Checked water pump, thermostat, hoses lickings, radiator, fan coupling, electric fans, including engine head gaskets (head’s pressure have also been tested Ok) but it can work (at 65mph), for half an hour at normal temperature but in less than a minute, it goes up (I have never run it up to maximum), but if I reduce speed to minimum (20mph), temp goes back to normal again. Testing it, I took out thermostat, locked fan couple but it react same way. Sometimes setting heater at maximum reduces overheating speed. If you have any idea, on how to save my Disco, I will appreciate! Thanks!

 

[Disco Mike]

Start with having your radiator rebuilt, it is most likely plugged, then check the viscus hub for proper operation.

 

[SNorero]

Thanks for answering. We have locked the viscus coupling, in order to discard problems, but did not have any advance but additional noice (and probably some other ineficiencies), I will check radiator again, it could have been repaired wrong way last time. An additional information is that I noticed some coolant drops in the back side of the engine (where it is assembled with transmision) could it be a seals problem? Thanks again!
Sandro

 

[Disco Mike]

Coolant, leaking from the rear of the engine is either a leaking valley pan gasket or head gaskets, either of which should be fixed ASAP.