proper engine temp. (was Heater Core Problems on 1989 90)

[duandcc_forums at cox.net]

Interesting. My oil temp according to the digi gauge is running a bit high. At sustained highway speeds (75-80 MPH) it will creap up to as high as 140-145* C during summer with the AC on. One thing I did notice, and I think is attributable to bad grounds is that if I turn on the blower on high or press in the cigarette lighter, the temp rises an indicated 10-15* in 10 seconds. obviously it is not really going up, just a false reading of some sort. But the slow creap up worries me. Even in windter it has a tendency to creap above 90* C (up to 110 or so). This is running 20w50 dino and an OEM filter in my NG... Thoughts?

Dave
1987 CGT Special Build
SE Virginia
>
> From: Dave Hord <spokes at the-wire.com>
> Date: 2003/01/21 Tue PM 04:30:13 EST
> To: Brady Moffatt <bradym at sympatico.ca>
> CC: human747 at attbi.com,  quattro at audifans.com
> Subject: Re: proper engine temp. (was Heater Core Problems on 1989 90)
>
> Hmmm...indicated temp, or actual temp :-)
>
> Never the same IMHE!
>
> For oil, I understand that proper operating temperature is at, or slightly over
> 100 degrees celcius.  In my opinion, THIS is the temperature that matters
> first.  It needs to be above the boiling point of water so that any moisture in
> the oil gets boiled off. This also helps boil off impurities.  Anything
> reaching 130 degrees celcius is too high, although maybe seen under hard
> running conditions such as track days.  If the oil is near 130 degrees celcius,
> I won't shut the car off without letting it idle and cool a little.
>
> For the H20 temperature...My understanding is that it should be right around
> the 90 degree celcius mark.  Again, under hard operating temps it may
> climb...but 90 degrees is what you're aiming for.
>
>
> I don't remember where I learned the first...it's been a number of years now.
> But I surmized the second based on the fact that EVERY car I've ever owned has
> had the fan turn on when the coolant measures about 95 degrees celcius.  So, I
> figure that 90 degrees is about perfect.
>
> Now about those gauges...Nothing reads the same. A new sensor might read
> differnt then it's buddy on the shelf.  I use two thermometers whenever I buy a
> new car.  I run the car until I believe it's at proper operating
> temperature...usually I do this after a 2 hour drive home, when I KNOW it's a
> proper temp.  One thermometer gets dropped in the coolant while the car is
> tossed up on axle stands.  The second thermometer gets put under the HOT oil
> that's draining out of the car.  I then compare my readings to what the gauges
> were showing.  If the oil and H20 temp are correct on the thermometer, I just
> ignore what the numbers on the gauge say and note the 'position' of the needle.
>
> FWIW...my VW rabbit was spot on. My audi with it's original Aux gauges was off
> on the oil temp.  With the 4kq gauge, it's spot on.  Same sender though ;-)
>
> -Dave
> ---------------------------------------------------
> 89 90q  300km+ Rally Conversion...
> Roll cage shots available at:
> http://home.the-wire.com/~spokes/rollcage/page1.htm
>
>
> Quoting Brady Moffatt <bradym at sympatico.ca>:
>
> > Hi All,
> >
> > What coolant temps are you getting, and what do you feel is proper? My 4kq
> > seems to run at an indicated 105 in summer, and anywhere from 85-105 in
> > winter, depending on conditions. I now have a high-tech piece of cardboard
> > blocking part of the rad, and I get better heat. I already had an 87-92
> > t-stat.
> >
> > Cheers,
> > Brady Moffatt
> > Montreal, Quebec, Canada
> > 86 4kq with 304,000km
> > 86 4kq parts car
> > 72 Datsun 240Z with 180,000 miles
> > 92 VW Golf with 194,000km FOR SALE
> > in early stages of quattrosis accumulatus
> >
> > ----- Original Message -----
> > From: "Dave Hord" <spokes at the-wire.com>
> > <snip>
> > >
> > > As a side note, it's also letting the engine get up to what I feel is
> > proper
> > > oil and H20 temperatures.
> > >
> > > -Dave
> >
> >
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>