Interesting! Just to muddy the waters a bit more here's my 2pw. My gauge regularly reaches 100 in traffic (maybe it's 97 in real life) before the main rad cooling fan cuts in. With the aircon on ECO, the temp rises much more quickly than with the compressor running, presumably because the aircon fans are either off or on low speed in ECO mode.
I recently had a near-boiling experience where the main cooling fan and offside aircon fan failed and only the nearside aircon fan prevented catastrophe, cutting in way above 100 and bringing the temp back down to 100. This happened in traffic but the temp never dropped below 100 even on the motorway at 70.
Not having the time to faff too much with diagnosis, I took 2 days off work and replaced the rad, the thermostat and the transfer pipe (ok it didn't take 2 days to do the jobs but there were parts runs by bus involved!) I did all this because I was convinced the fans were only half the story. It felt like a blockage because I assumed that at 70 there would be enough air rushing through the main rad to cool it. I traced the fan failure, completely by fluke, when I pulled this fuse here and found it to be broken.
All was well until 3 weeks later this fuse blew again in heavy traffic with aircon on and again the temp would not drop below 100 even at motorway speed. Replaced the fuse again and it's back to normal.
So lessons learned are: 1. the fans do a hell of a lot more than I thought to maintain normal running temp and 2. I have a wiring issue that is causing this fuse to blow. Far cry from my Monza, which has a Kenlowe-controlled fan behind the rad and nowt else (granted, no aircon either!) and only needs to be doing about 40 to get enough air through the rad to keep the fan off.
By the way, has anybody ever heard fizzing under the plenum cover when the engine's hot? I suspect my thermostat housing isn't sealing properly, which is annoying because I heard it before the thermot**t change as well. I'm thinking of investing in a torque wrench and attempting the cambelt (thanks for the DVD TB!) and when I do I'll check the thermostat bolts. Only two of em so I reckon if they're not exactly right you get a bit of a leak.
Back to the original post: my gauge reads pretty much what yours does and it sounds fine, but flushing out all the old coolant can't hurt. Drain, refill with water only, run it, drain again, repeat about 6 times, refill with 50/50 mix. I had to make sure al lthe old stuff was out because I was putting red stuff in where previously it had been blue and I've heard the two don't like to mix!
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Topic: Water gauge/temperature - 2.5cc V6 (Read 2514 times)