ceedee

my cars temp is one notch below red... so it's 3/4 sort of
is that considered hot and what can i do to change that? it's an 1983 928s...btw

Richard S

Sounds too hot to me. Best thing I ever did to my early cars to lower the temp was remove radiator and blow out all the crap that was between the fins. Blow compressed air from back to front, be ready for a huge cloud of dust, dirt, bug parts, etc. Straighten out any bent fins. Next, blow out the A/C condenser the same way (no need to remove it from car). Clean out all the crap collected between condenser and radiator. Re-install radiator. Drain engine block coolant as well, then refill it all with distilled water and correct type of coolant. Next step could be new coolant tank cap, new t-stat, low-temp fan switch, repair of viscous fan clutch if needed, etc. Start with the cheap stuff first.

BTW, my early cars both hold at the lower white line. During open road races in the Nevada desert at speeds around 130mph and 100 degrees summer temp, the needle would be at the upper line.

Good luck, Rich

zoltan944

that is too high. i think your viscous clutch fan is going. Reeplace with efan and clean up the radiator and change the coolant as mentioned above. I use a 75/25 water/coolant mix with water wetter.

neilh

"my cars temp is one notch below red... so it's 3/4 sort of"
zoltan944 probably right on,
Usual questions which apply:
All the time
only in traffic
only with air on
no problem when on the open road

BIMMERMIKE

I have the same problem,

I have replaced viscous fan(new)
lower temp new thermostat, new 'o' ring
changed out coolant, drained block 50/50 mixture

no problem on open road
only in traffic.

neilh

So did I, thats why I asked.
Bought an IR thermometer, and it shows that everything is good, the temp range across the radiator, the hoses, top of block, etc, are all looking good.
Gauge sits around horizontal - 10 o'clock position, creeps up a little in traffic, but so long as the overtemp light stays off and the electric fan doesn't turn on
i'm 'dumb and happy'

BIMMERMIKE

The gauge sits just above the first white line during open road travel.
My overtemp light and efan has never come on, but it to see that darn white needle creep up in traffic to the upper limits.

Normy

Bimmer-

Sounds like an air flow problem. If you're sure that your t-stat is correct, in good shape, and installed correctly, then you aren't getting enough air in traffic. If you want, you can "hot wire" your auxiliary fan to run and see if it cures the problem.

Looking at the front of the car, the lower right [drivers side] corner of the radiator has a temperature probe with two wires coming out of it. Make a jumper wire with two male prongs and connect these wires together. From then on, whenever your ignition is on, the electric fan in front of your radiator will run and this should solve your problems in traffic. If not...there's something else wrong.

-For what it is worth, I've driven my car for several years like this; the car runs at the lower tick most of the time, only reaching just above in stop and go traffic on 33 C days.

N!

zoltan944

gets hot only in traffic = fans (retention, get new one, change to efan)
gets hot all the time, even going 60 on freeway = flow problem- clear debris from radiator, change fluid, check tstat, etc....

zoltan944

drain the radiator only, and fill with distilled water only to reduce your coolant level and see what happens

BIMMERMIKE

Help me understand, why only distilled water?
I replaced my t-stat, is there another seal other than the 'o' ring that need to be replaced? Any pics or diagram showing other seal. I have read somwhere but never noticed, that if seal is missing or deteriorated then hot coolant can flow back into engine block instead or radiator.
I have drained coolant at least 3 times in the course of a year trying to solve this issue!
86.5 A/T 110K miles

zoltan944

cause there is no calcium and other minerals/deposits as in tap or drinking water.
deposits+aluminum=BAD

Brian B

My 79 runs up towards the three-quarters line, too. When I checked the temp at the thermostat and the radiator with an infrared thermometer, it was right at 75-80 degrees C, so I guess my guage reads a bit high...

I still want to flush the system and clean out the radiator, though...

BIMMERMIKE

That I understand, nut why not a mixture of distilled water and antifreeze?
why just distilled water?

airosey

My 81 doesn't even have a fan anymore and it never goes above the middle line. I had bought an electric fan to replace the viscous, but even in heavy traffic, the a/c fan kicks on when it gets to the middle line and brings it back down. During cruising the needle stays between the bottom and middle marks.