PMF, DQ or not giving enough relevant info. It's only a machine not a first born child.

......

 

Dick.

 

Find out how high it goes. I'll hit 204. Not happy with it, but it's something that's endemic.

 

zeroone, i guess is a disco ,v8 4.0, what kind of milage you have on it, if its over 150k
probably you have clogged block or head water passages, to fix that , replace head gaskets and it´l be ok, cheaper knock off the thermostat, will cost you more on petrol. longer time to warm up.

 

147k. Heads where just done, coolant system is new-ish save for the burp tank and heater core.

I'll just drive it once in a while until I figure out what it's deal is. It's perplexing to me. With my luck, my 1.5 year old rad is clogged.

 

I have been keeping my control unit blasting at one notch under max speed, automatic, and recirculate mode all engaged. This helps to keep the temps on mine somewhat evened out between 196 and 201. Sometimes cruising the highway, it will get down to 194 and have seen it down to 190 a few times. 196-198 the other 75 percent of the time. I don't get how it can be 194 or 198 at same speed, ambient temp, etc. when I start it cold it will idle at 194 and stay there. Start moving and engine temps do whatever they want from there. I'm going to order a real thermostat and other gadgets to try something new.

 

Been doing the same, except, mine will not maintain temperature at idle as far as I can tell. If the auxiliary fan comes on I will shut it off.

Drove it all weekend. Never let it idle, never saw greater than 203 climbing a very steep hillike at 25-30mph. I was panicking... lol

 

Pressure test it.

 

I'm not losing coolant.