924Board.org

[epsylon]

Here is what I have found out thus far:

1 Radiator has 30% blockage, getting that rodded out and cleaned up (i am hoping that this solves the problem).

2 Car doesn't appear to use coolant fluid, tank is always at fill line (should eliminate the bad gasket senerio, right???).

3 Mechanic says fans work as they should and blow strong.

4 Water pump is not leaking and mechanic says it is working.

5 When I bought the car it look as though there was mostly water (very dirty) instead of a 50/50 coolant mixture. Now I know why. After it got close to overheating the first time I drained the fuild and replaced it with a 50/50 mixture. I wasn't thinking about water versus coolant cooling properties. I live in Texas so I think I am going to add more water to the mix.

They should have the serviced radiator in by tomorrow so I will know more then, I'll keep you posted. If the problem still exists then I'll have to assume it is a bad gasket. I just wanted to say how greatful I am to everyone. I have learned so much from your suggestions/advise. I feel like I have a real resource for tourbleshooting my 924. Thanks.

[Jrod-13]

I have the same problem on my 924. I flushed the system.. and refilled with straight water. The problem ceased,for about a week, but then today i drive it into town.. and parked it and let it idle.. about 2 min. later it was up in the red(almost). but since then.. its been fine.. I also noticed... that every time my subs hit.. the needle jumps.. hmm.

Also the water pump is 1 year old.. so thats not it. my guess is a blockage.
Jared

[epsylon]

the cleaned/declogged radiator seems to have helped. the car no longer overheats. i drove it 5 miles and let it sit for a while and the needle now sits a the 3/4 ( one notch below the redline, not in the middle though).

i have a question as to how long the fans are supposed to run after i turn off the car. my driver side fan ran for 10 minutes until i disconnected the battery ( i had to go back to work and didn't want it to drain the battery ). i am going to see if it turns back on when i reconnect the battery when i get home (engine will be cold by then). if the fan does turn back on could i have hooked the fan up incorrectly to where it now runs all the time???

[ltgland]

My car was having problems with teh fan until I sanded down the grounding rings and petroleum jellyed them. Its about 45 minutes work in a crappy position, but it helps most lekky probelms, my fan actully comes on, and lasts about 5 mins when I switch off

[numbers]

In a hot climate like San Antonio, having the fans run for 10 minutes after shutdown is not unusual. Also don't be surprised if the fans come back on after they have shut down once. Anytime the radiator water reaches the temperature of the fan thermostat they will go on. However, they are running at a reduced rate, because of the fan resistor. The fan resistor is bypassed when the key is turned on by the fan relay. That is why you will hear the fans run much faster if you turn the key to the on position when the radiator water is still hot.

[epsylon]

i got home reconnected the battery and bingo, fan came on. switched the positive and negatives and still came on. engine is cold and has been for several hours.

is there a chance that when a thermo switch breaks it can be stuck with a complete curcuit? the part seems simple enough to replace does anyone know where i can get new one cheap? part number ect...

[924RACR]

Yep, sounds like the fan switch (in the radiator) is shorted... most likely... naturally, the part numbers for the various options can be found on the 924.org Parts page...
http://www.924.org/parts/parts.htm

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Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype