txhokie4life

My 928 (82 Euro S 4 Speed) has always run a little warm according to the gauge.

I'm in the midst of resto -- so I couldn't feel confident everything
was on the up and up. I'm getting closer to completion (or at least saying that phase 1 is done :-)

I've since have had my gauge cluster rebuilt, replaced my thermostat, rebuilt my radiator, moved the AT radiator to be external (all for various reasons).

Finished the thermostat last night. Car sits at 10 oclock gauge line during extended idle with 1 or 2 fans on. Ambient temp was ~80-85ish in the garage.
This seems to be about where I was pre-thermostat change. Both
thermostats are 75C.

I have a temperature meter -- so I can measure temps if I knew
exactly where to be looking.

I'm seeing about 87C at the passenger side (water exit?) of the engine, and 77-82C at the thermostat housing.

I idled it about 30 minutes, didn't appear to have any air bubble issues. At least I didn't have any substantial movements in the water bottle or any overflowing once I got the level stable (about 5 minutes into idling)

What idle temps should I expect? Where should I be measuring?
What are the values at the various points on the gauge?

Thanks,

Mike

Speedtoys

185 on the sharktuner is dead on the bottom white line (1/3rd up the gauge) in my S4.

Right bout 210 on the ST is the top line, (2/3 up)

But that's my, don't expect the same on these things.

WallyP

The temp gauge is an approximation, not a precision instrument. Don't fret over exact needle position.

You will usually be able to tell if the engine is too hot - it will feel hot and will smell hot.

The engine is designed to run at about 90 deg C. In cool weather, you should see about 85 - 90 at the upper water neck; hot weather, 90 - 95; hot weather, AC on, sitting in traffic, 95 - 100. If you run your car on short trips, you will have accelerated wear and oil contamination, as the huge oil pan means that your oil will never get to full temp.

If you use your AC in heavy traffic, I would suggest using an additional relay powered by the line to the compressor clutch, that sends power to the electric fan anytime that the compressor is operating. Your car triggers the fan by coolant temp or refrigerant temp, and the refrigerant temp doesn't do a very good job of controlling the fan.

txhokie4life

Well I do fret :-) -- She's an old girl with original head gasket and I don't want to press my luck
--- Live in Texas where it's HOT and engine always seems hot and smells warm to me -- but, I don't have a reference :-(

If I wanted to add an additional water temp gauge -- where would be the best place to plumb the sensor?

thanks,

Mike

danglerb

Where to put it depends on what you want to know.

Exit of the radiator would tell you if the cooling system is working, and how well.

Entry of the radiator would tell you if the engine is getting too hot.