Well I have done my HG's, new Thermostat, fan and flushed system and my temps while on the highway (scan gauge) are running 197 and as soon as I stop 207 and sometimes 211. As soon as I get movin they come right back down but the up and down temps drive me nut! I just feel like that is to high and wanted to get some input from you guys. I am thinking of doing the thermostat mode and wanted to see what the overall opnion of that is and some pro's and con's thanks.

2004 Disco SE
Straight Shooter

 

When you say 'fan', you mean the fan clutch, right? Is the AC fan functioning properly? IMO, I think I'd make sure those were good before I went down the in-line thermostat mod path...

 

Your numbers are EXACTLY the same as mine (on my 38k mile junkyard motor that I'm running while I rebuild the original).

You aren't the only person reporting these exact numbers.

Would I like them to be lower? Sure. But the reality is that the aux fan cut in is set at 209 from the factory. If 211 was a problem, wouldn't the cut in be lower? Also, it's really common for motors to be running at these temps now. LSx motors have been 210 for quite a few years, and they are all aluminum just like Rover motors.

I'm not sure it's an actual problem, but I haven't 100% convinced myself yet either.

 

Had similar problem with used high miles (172K) 97 D1. Normal temp down the road. Noticed it was warming up when sitting in traffic or parked. Got a scanner and saw that what the gauge said was "normal range" was 231 F. Did fan clutch, that helped. Flushed radiator, that helped. Rodded out radiator ($65 at a shop) and that helped. Installed a "high flow" thermostat - that helped on the road. But park it and in less than 10 minutes I was at 220 and climbing. Only with AC on. And AC would blow warm air when parked.

AC fans were wired backwards by PO, fans had been swapped out with salvage yard ones. This sucked hot air from main radiator onto condenser, made AC compressor high side go to the max and trip the safety cutout switch. Fans were blowing air out the front, subtracting from the air moving backwards by the viscous clutch fan. Net air flow was about 150 cubic feet a minute. Reversed fan wires and all good, cruise at 174 - 178 F at 60 mph, get up in the low 200's when parked, 95 degrees outside.

 

Mine are right at the same numbers - had an ultragauge hooked up and it started beeping warnings at me while driving and I could not figure out what it was - turns out it has a default warning of 210 and I must of exceeded that. Everything runs fine, so I am assuming this is normal for a Disco - at least I hope it is!

 

Oooof....that's the kind of ugliness that makes you want to find your PO and beat them about the head with a pipe wrench.

 

Ditto, 196ish hwy 203ish in traffic. Reliable as rain on the day I plan to mow the lawn.

 

Mine runs about 194 on highway and up to 205 in the city, sounds like you're running in the right range

 

pretty much what everyone else has said. I did a full flush two weeks ago along with changing out the expansion tank cap. I run... 193-197 at speed over 45. 198-202 at speeds 10-40, and if I am stopped in traffic or come off highway ramp to a stop etc.. I run 200-207. The electric fan should be set for a turn on at 207 not 209. I have seen temps as high as 215 but that has been after a highway run and then comming to a stop at a light or heavy traffic. I have also found that if you are stuck in traffic for a bit and the temps start to climb you can put her in neutral and bring the revs up to around 1650... this moves enough extra air to bring the temp back down to 200-202.