Thread: Disco 1 overheating - help needed

Is it using any coolant? during general driving? Any water in the engine oil?

If its not using any water and just gets hot when under load i would say the radiator needs rodding. In the disco radiators the veins in radiator run horizontal so you dont flush the all the crap out with a general coolant change. The radiator needs to come out, take the tanks off the end of it and use rods to push the crap out of each channel in the radiator. Sounds like this might be your problem, especially if it runs fine when not under load but heats up quick when you give it some. It sounds like the radiator cant get rid of the heat quick enough when lots is produced. Has it got the original fan or has someone added thermo fans or anything like that?

Maybe you have an airblock somewhere in the engine that is causing a hotspot?

have just bought a 94 discovery 3.9 v8 auto with eaton supercharger.
Have replaced radiator, viscous unit and fan, all new coolant and pressure flushed engine, checked water pump which looks brand new (think last owner having problems also as all plastic under bonnet is very brittle from heat), checked hoses, replaced thermostat and checked new one to ensure working and tried it without thermo stat, pressure flushed entire system.

Did you replace the radiator with a NEW one? This certainly sounds like a blocked radiator so I would revisit .

Although seeing it has an Eaton Supercharger-
I wonder if the ECU is pulling out so much advance when the supercharger goes on boost that the amount of retard is causing overheating.

What sort of ECU is the car running?
Is it a MAP sensor type?
Does it now have an electronic advance control?

It is almost impossible to diagnose something like this from a distance without knowing how mods were done to the car.

I suggest you contact the fitters of the supercharger.
Regards Philip A

This sounds EXACLTY what my old 6.5 chev deisel was doing, would cruise ok but under any load would get hot, i ran a new patrol 4 core radiater which is alot bigger and it was still doing it.
Fixed it with a 80mm thick 2 core aluminium radiater, didn't get above 90c
then i stripped and sold it
Radiater just wasn't big enough, or wouldn't flow enough

Check exhaust temperature as the supercharger could be causing the combustion temperature to be too excessive for a standard cooling system
Air fuel ratio should be checked, possibly running too lean under load.

Originally Posted by The Bullfrog

IF ANYONE CAN PLEASE GIVE SOME OTHER SUGGESTIONS????

^^^^ Go visit the "Poster" above me ^^^^^^^


And seeing someone with a Dyno wouldn't go astray


In the meantime .... stop driving it till you get it sorted , otherwise you WILL be up for a new motor


Mike

Also check to make sure that the air is actually going through the radiator, air will take the easiest route and if it can go around and not through the radiator it will

My fathers rangie was doing similar this to what yours sounds like its doing, we blocked the gaps and so far it seems to have improved it drastically.

Originally Posted by GuyG

Also check to make sure that the air is actually going through the radiator, air will take the easiest route and if it can go around and not through the radiator it will

My fathers rangie was doing similar this to what yours sounds like its doing, we blocked the gaps and so far it seems to have improved it drastically.

Making sure you haave a decent radiator cowling will make a world of difference to this aswell.