MY disco hit 217F at idle today so i think its time for a new thermostat.Where is the best place to get a 180 thermostat from..............thanx

 

This is not unusual.

1) Is your radiator operating to full capacity? Is all the dirt and straw removed from the fins?

2) Fan clutch - may not be operating fully.

3) Electric AUX fan must be running at idle. It will eventually come on.

4) When A/C is on, an additional fan should fire up.

 

Autozone. They carry a "failsafe", meaning if it gets stuck it'll get stuck open instead of closed, for around $10. They're not hard to find.

Edit: Disco I or II? Just dawned on me that the II takes a different kind of thermostat.

 

The failsafe T-Stat that AutoZone carries doesn't apply to the Discovery II.

The 180º thermostat is a good start, but you would do well to replace your radiator. If it's never been done, then it's definitely time.

 

Thanks all for the reply.When im at idle the temp goes up to 217,when i rev up the rpms alittle it will go down to 208.Mabey i should just unplug the ultra gauge

 

lol

In addition to the radiator, the water pump might be a good idea too. And not too expensive either.

 

Go up a long hill and see what it is then.
Your fan should be roaring.
This is where it matters.

At idle - you should get the AUX fan on eventually.

 

Perhaps in the meantime you should unplug the A/C and then turn it on. This will bring on an additional fan while you try to solve this issue... so you can drive it without overheating!

 

here you go

 

my stat was restricted. I think it was just stuck, I could also rev the engine and drop the temp a lot. replacing my stat droped my idle temp to 194 and highway to 188.