jim beam <me@privacy.net> wrote in
news:_tOdnZWS2OugLtHXnZ2dnUVZ_j9i4p2d@speakeasy.ne t:

> jim beam wrote:
>> Tegger wrote:

>>>
>>> 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.
>>
>> http://www.flickr.com/photos/38636024@N00/2445120839/




I'm going to assume this image is accurate, since I have no evidence
otherwise.

In any case, the apparent buffering or non-linearity does not matter. A
cooling system in good condition will handle about 235F before the fluid
risks bursting into steam.

If the gauge needle gets just a bit past half-way, the "sweet spot" at the
upper rad hose inlet will show...just about 235.

The point is that you need to keep an eye on the gauge all the time. The
gauge /is/ a very accurate tell-tale of a situation that may lead to severe
engine damage, even if it can't give you /exact/ information.

If the needle starts to rise, TAKE ACTION AT ONCE. DO NOT ALLOW THE GAUGE
TO APPROACH THE RED LINE.
The further from the red line you can keep the gauge, the greater the
likelihood that you will prevent the engine from getting wrecked,
regardless of any (im)precision inherent in the gauge itself.


>>
>
> and that the gasket can be gone well before the gauge starts to show
> problems.
>



Usually the head gasket is gone well before any symptoms surface.

People often notice once the car starts overheating after extended idling
in heavy traffic, or they notice the fluid reservoir level is WAY high,
with bubbles evident with the engine running.





--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/