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Hey guys,
have you noticed if the V6 is sensitive to being low on coolant?

I left my house today and made it about 5 blocks when I noticed the temp rising faster than normal, so I turned around and when I got home it was right at "H". I let it cool for about 45min to an hour and topped up it up with about 1.75L of boiling water and now it's fine. At first I was sure it was the thermostat, but it's running OK now? In my experience, once a thermostat freezes shut, it stays that way.

are you sure your water pump didnt break

If the water pump broke, I would still be having problems. It's totally fine now. I have driven it 3 times since then.

Check your anti-freeze concentration, if you topped up with plain water - it may be too dilute.

And watch the level daily - that lost water indicates a leak.

<small>[ December 09, 2004, 02:32 AM: Message edited by: IanL ]</small>

Water pumps that are wearing out often start leaking small amts. of coolant from around the pump shaft, with the leak getting progressively worse before they go altogether. 1.75L is a lot of coolant to have to add. Worth keeping a very close eye on the coolant level and search for a leak if the level goes down again at all.

Also, though this doesn't sound like a thermostat problem, a thermostat going bad doesn't necessarily stop functioning all-at-once. It can act flaky for awhile first and open only partially before it eventually stops functioning completely.

thats strange...i changed the anti freeze and my car would take forever to get hot...with the thermostat closed. I wanted it to get to middle temp so that it could start bubbling where the readiator was cracked..anywho... i bought a new radiator. But well mine takes a good 10 minutes to warm up and also with low colant it never heats up all the way.

You may have gotten a different temp thermostat. That would cause the car to run at a lower temperature. They sell different temp at which it will open and close.
As for the guy who put straight water into the car, you need to use mineral water in the car it is easier on the seals. That is if you care about keeping the seals in good condition. Also most thermostats when broken will stay open not closed. They have spring that pushes them open, if they aren't working it just won't ever close.

Hmmm... I've had to replace maybe 8-10 thermostats over the years. Never had one that needed replacement because it stopped closing though. Only ones that acted up by not opening fully and all eventually refused to open at all... I've heard they can get stuck open but thought that was a fairly small percentage of ones that malfunction.

Originally posted by perhapsadingo8yerbaby:
Hmmm... I've had to replace maybe 8-10 thermostats over the years. Never had one that needed replacement because it stopped closing though. Only ones that acted up by not opening fully and all eventually refused to open at all... I've heard they can get stuck open but thought that was a fairly small percentage of ones that malfunction.

My experience too.

I think I might not have been clear. The waterpump is not leaking. I have a very small leak off the composite flange on the driver side of the rad. Just too busy to get to it. I just have to top it up about once a year or so with about a litre. I hadn't top it up in a long while (over a year). Prior to the overheating I was noticing that when it was idling, I wasn't getting hot air through the heatercore so I knew I must have been low in coolant again. Now, the real question was if I am down in coolant (approx 1.5L), will the flow of water be restricted to the point that the engine overheats. If not, then my thermostat must have stuck shut and then coincidently unstuck after I topped it up, because I don't have any over-heating problems anymore. And I get hot air through the heater core when it is just idling.