Thread: Cooler running Thermostat

Best mod I ever did.

While I have a 4.6, used to get up to 98 intraffic or more if a hot day and I'd sit there sweating. Now sits on 87, either at 20deg on the highway or 40deg in traffic.

Originally Posted by clubagreenie

Best mod I ever did.

While I have a 4.6, used to get up to 98 intraffic or more if a hot day and I'd sit there sweating. Now sits on 87, either at 20deg on the highway or 40deg in traffic.

Does this thermostat fit straight into a 3.9? Cheers

Originally Posted by Devomorris

Does this thermostat fit straight into a 3.9? Cheers

No the thermostat will fit Freelander & Disco2. It is in the coolant hoses where as a 3.9 has a metal thermostat generic type at the top of the engine. You could fit an 82 deg on to your 3.9. Pretty easy to come by at any auto store.
cheers, Mario

Yeah, we D2'ers wish it was back to a std system. Looked at it but not sure of the effects of reverting some of the flows.

There is also an inline unit available that uses slightly more substantial thermostats and you don't need to disassemble engine bits to change. It's an alloy screw together, oring sealed unit that just fits inline in a hose. Available from Sumit Racing, just order the right hose size unit and thermostat. A common D2 mod before they found the freelander units.

every land rover mech ive spoken too says both the v8 and the td5 are meant to run hot and lowering the operating temp moves the engine out of its efficiency range.

And keeping it hot moves it into their repair pricing range.

I'd rather the liners stay where they are and it be cool than rebuild every time the temp goes up. Anyone that needs to design an engine to run over 100deg for "efficiency" needs a good look at themselves.

An aftermarket ECU and a play will bring things back into normality.

Originally Posted by clubagreenie

And keeping it hot moves it into their repair pricing range.

I'd rather the liners stay where they are and it be cool than rebuild every time the temp goes up. Anyone that needs to design an engine to run over 100deg for "efficiency" needs a good look at themselves.

An aftermarket ECU and a play will bring things back into normality.

Mine, at the moment, rises to 100deg ( a bit unsettling ) before it then drops to about 90 and settles there. Figured, if the thermo opens a little earlier it may get to 90 and stay there.

On a slightly different note, I've turfed the elect fan and gone back to the standard. Have just ordered a defender V8 cowl to see If this will sort out cooling issues. I'm using a 4 core cut down disco 1 radiator with oil cooler on one side and auto cooler on the other. Does anyone know if cowl will do the job and what are others using on 3.9 auto defenders/county?

The viscous fan with correct cowl should work well. I'd rather see an early (or any) engine cooler than that.

By comparison Toyo 1 & 3UZ's I've built have ran at 10,000+rpm for half an hour to an hour straight on a std toy cooling system and don't pass 88.