Normal Operating Window of GTA Turbo / Water Temp Gauge

Chaps

I've done a bit of Forum searching on the matter, but couldn't find exactly what I'm after so hope you can help.

I wanted to know what the average Water Temp should be displaying on the gauge (1990 GTA Turbo) after a jaunt out in the weekends 25 degree heat.

Basically, the gauge shows it runs up to temp normally suggesting 80 to 90 on the gauge whilst driving for 15 to 20 mins or so. Whilst driving a little more 'spirited', it may go to 90 to 100 especially in the 25 degree heat we had at the weekend. I can hear the front fans and the rear fans (are there 2 at the rear though?!) kicking in and it never loses any water from the header tank. For the last 10 minutes of a 45 minute run,it was around 105 on the gauge, and just as I pulled down onto the drive after being stuck in a little traffic, the turbo fans kicked in and the light came on. Not sure if this sounds like it's functioning properly or not? Car performs perfectly though, no leaks underneath and never loses any water. It's had a new radiator put in with 2 new Spal type fans and I've noticed a dial under the bonnet which could be to control the temperature they kick in, and it's in position 3 of 5 at the minute.

Any suggestions... does this sound normal? Are the temp gauges about as reliable as most other electrical components on the GTA?! Should I be investigating?

Thanks

Chris

I think it all depends upon "how much" spirited driving and at what speeds too.
The car does seem to like high speed, 60mph plus, to get good airflow through the rad to make it work well. Town driving will cause temps to rise for sure.
Certainly does not like track days on tight tracks as much where there could be a lot less air through the rad.
Mine sits at 80 deg C when cruising at 60mph, and 90 deg C when cruising at 80 or above.
It could be worth making sure there is no sludge or sediment in the rad, but this can involve removal.

The rad has input and output half way up on each side, so it can easily collect some sludge and sediment in the bottom half and start to block the lower cores.
Some say, that you can feel the bottom of the rad not running as hot as the top, but i suspect that will only be in extreme cases of blockages.

You can disconnect the water hoses from it, while in situ, and flush through with a water hose, and just see if the water is rusty and sludge like that comes out. Flush it in both dorections too.
Or remove it and lay it flat while jiggling water up and down the cores.
Then put just a little water in it, see if it flows through bottom cores and if not, you can suspect the bottom cores are blocked.

It may be that your car has a new rad, in which case it should not be any issue.
I am told these motors can run at 100 deg C all day long.

Other thing that is really important to good cooling is the ducting from front bumper to rad. Make sure the ducting fitting is good and the duct is not broken and allowing the good clean cold air to escape from being forced through the rad.

Mine performs pretty much the same as yours Chris.
It doesn't like traffic and I always get a little anxious when I've been stationary for a while watching the temp gauge gradually creep up.
Was (and still am) thinking of fitting an override switch to turn the rad fan on to cool it before it rises to 100 and beyond. Still on my list of things to do..

Mine is pretty much the same.

My car does have a rad fan override switch which is really useful in town. The engine fans stay on for a few minutes after switching off if the engine is warm. (I think over 60 deg.)

Paul

Upon re reading the OP, i see a new rad is installed. so it should not be blocked in any way.

Sounds pretty similar to mine.
Rises pretty quick if kept idling for a while, but the fans kick in just over 90 and it drops off again.

Takes surprisingly little airflow to cool it quickly again.

My rad fans turn off with the ignition, but turbo cooling fans will cycle on and off for 10-15 minutes after switching off if eithe rthe motor or ambient temperatures are high

To be on the safe side, every few months, bleed the rad to make sure there is no air in it. Any air that may be kicking around will always find its way to the rad, and because of the position of the in/out pipes, the air will make its way to the top of the rad and stay there.
If you want to be a geek like me, jack the drivers side of the car up a bit, so any air will collect where the bleed pipe lives. Also, remove the reservoir cap, and whilst bleeding, remove the bleed plug completely to insure a fast flow of air/water ....... it always amazes me how much air collects in the rad.
Bleed until a clear streem of coolant is seen, and make sure you keep topping up the reservoir whilst doing this ...... you dont want to introduce any more air into the system.

PLUS....... you can use the liquid that is bleed out of the rad................. to refill the resivoir
This saves watering down the coolant mixture.

I sense the the temps seen are about par for the course.

My turbo engine seems to stay below the 90 mark...but has had the benefit of a rebuild (after a fire) ...so the coolant can do its job...no crud/corrosion to clog up the internal cooling channels)
(I think the previous owner of my car had some cooling temp concerns...based on posts here)

I think bigger rads/fans that some fit help mitigate the years of crud.

My atmo does run hotter in traffic...maybe for the same reasons above.

This engine sounds like an AC model (twin fans) and that switch mentioned the AC thermostat ??...if that the case you can switch the AC on to keep the fans running..a basic override... Also with the AC on you can have the heating on...another way to take some heat out...

Any chance of a pic of the gauge Chris? Ideally it should stop at the little tic mark and go no further. Ideally.