Tegger wrote:
> jim beam <me@privacy.net> wrote in
> news:d-ednfLhtO5DtNHXnZ2dnUVZ_rKdnZ2d@speakeasy.net:
>
>> BT wrote:
>>> Car: 1999 Honda Civic CX (Hatchback)
>>> Miles: 242,000
>>> Location: Southern California
>>>
>>> Symptoms: Sweet smell when I started the car Monday morning. Thought
>>> my daughter had dropped some candy or something and ignored it.
>>> Tuesday afternoon, while driving up a hill at ~50mph, I noticed the
>>> engine temp gauge needle rising pretty quickly. It got about 3/4 of
>>> the way to the top while I was looking. I was in the process of
>>> slowing down to make a left turn, so took my foot off the gas and the
>>> needle went down as well. Made it back home driving very slowly, and
>>> the needle never went above the halfway point (but it was still above
>>> where it normally rests). When I got home, checked the oil level
>>> (fine), coolant (near max) and if the rad fan was obstructed in some
>>> way (it was fine). Drove normally to the dealership after about 2
>>> hours, and the temp gauge needle was at it's usual spot just about
>>> the 3/8 mark.
>> gauge can't be trusted unless it's in the red - it's non-linear.
>
>
>
>
> Maybe so, but my infrared thermometer tells me the gauge is awfully good
> at informing you of overheating well BEFORE it gets into the red.
>
> With a 78C thermostat, you're expecting about 205F at the upper rad hose
> inlet at the head. As the gauge begins to climb above its "normal"
> position, the temperature at the inlet will climb to well above 205.
>
> Bottom line: Ignore the gauge at your peril! Once it lands in the red, head
> and block wapage is a virtual certainty! Catch overheating early and no
> harm is done.
>
>

ok, i'm not saying "ignore the gauge", i'm saying that "usual spot"
gives quite a wide range of temps.

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