Yet another overheating problem
#46
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Regarding temp differential between IN and OUT, I've never measured it before but will accept your opinion that 50degF is in range. Too bad - I hoped that the problem was solved!
Regarding fan noise pre and post filling - no difference to me. I'm too deaf...
Regarding fan noise pre and post filling - no difference to me. I'm too deaf...
#47
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get it hot again and see if the center or lower part of the radiator to the touch, is hot. if its hot top to bottom on your intial drive, your fans are just not doing the job. however if it is kind of warm at the bottom and hot at the top, then you have a circulation problem. could be the pump and usually is. the fans have no real bearing on temp if you can keep the speed of the car at around 40mph on any warm day. freeway speeds, dont need a fan. I race at thunderhill with no fans on 95 degree days and its below the middle line.
#48
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Gaz said, "...whether the main fan turns on when the aux is off..."
The S4 & up cars don't have main and aux fans - the two fans are equal, and should always be running at the same speed.
The S4 & up cars don't have main and aux fans - the two fans are equal, and should always be running at the same speed.
#49
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What?!?! Why do I never know anything about my car no matter how much I read?!?
Ok then does one fan or do both fans stay on for a few minutes after shutting down when the engine is hot and/or when A/C was running?
Ok then does one fan or do both fans stay on for a few minutes after shutting down when the engine is hot and/or when A/C was running?
#50
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A change in the noise of the fan is mentioned above. Fine, but I'm deaf, too.
Another way is to try to stop the fan when the viscous coupling should be engaged. Not an undertaking for the faint of heart of heart. No fingers, long screwdrivers, wrenches, or sticks - but I have seen a broom or whisk-broom used, gently, gingerly (and bristles first, of course) to push against the blades of the spinning fan.
Done right, you won't damage the blades but you'll definitely be able to tell if the viscous coupling is locked up and slow or stop the fan if its not.
Done wrong, you should make sure you've got a video going and preface it with, "Hey, y'all, watch this!" as you jam it in there.![cherrsagai](https://rennlist.com/forums/graemlins/drink.gif)
Pretty shade tree, but functional and dispositive.
Another way is to try to stop the fan when the viscous coupling should be engaged. Not an undertaking for the faint of heart of heart. No fingers, long screwdrivers, wrenches, or sticks - but I have seen a broom or whisk-broom used, gently, gingerly (and bristles first, of course) to push against the blades of the spinning fan.
Done right, you won't damage the blades but you'll definitely be able to tell if the viscous coupling is locked up and slow or stop the fan if its not.
Done wrong, you should make sure you've got a video going and preface it with, "Hey, y'all, watch this!" as you jam it in there.
![cherrsagai](https://rennlist.com/forums/graemlins/drink.gif)
Pretty shade tree, but functional and dispositive.
#51
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After the engine is off, the fans (both) stay on if the intake temp switch or the auto trans temp switch shows too hot. Low speed fan, and may be sensitive to hood switch position.
#52
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I have another thread going on my attempt to diagnose where the problem is (no current at the end of one of the fan cables) but am running into some diagnostic problems there. I PM'd Greg Brown over the weekend to get his input/opinion too, as you mentioned that he rebuilds the fan controllers.
#53
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While not contributing to the overheating problem, the coolant type should be the orange/pink colour type as it is the silica-free type needed for aluminum engines and radiators.
Recommend dumping/flushing out the cooling system and replacing with the proper DexCool type coolant.
Your overheating symptoms are typically associated with an inoperative cooling fan system.
Recommend dumping/flushing out the cooling system and replacing with the proper DexCool type coolant.
Your overheating symptoms are typically associated with an inoperative cooling fan system.
#54
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While not contributing to the overheating problem, the coolant type should be the orange/pink colour type as it is the silica-free type needed for aluminum engines and radiators.
Recommend dumping/flushing out the cooling system and replacing with the proper DexCool type coolant.
Your overheating symptoms are typically associated with an inoperative cooling fan system.
Recommend dumping/flushing out the cooling system and replacing with the proper DexCool type coolant.
Your overheating symptoms are typically associated with an inoperative cooling fan system.
Big yes to an inoperative fan system typically causing constant overheating unless major loss of coolant has occurred which would be obvious.
#55
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Gaz--
Try pulling a wire from the intake temp switch, see if the over run condition goes away. Those switches corrode inside if wetted, usually closed so the fans always run. BTDT while carefully rinsing under the hood, then a week later I notice the fans running
Try pulling a wire from the intake temp switch, see if the over run condition goes away. Those switches corrode inside if wetted, usually closed so the fans always run. BTDT while carefully rinsing under the hood, then a week later I notice the fans running
#56
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Gaz, I saw your comment a out opening the hood and the fans turn off. I disconnected my hood switch when I had cooling problems. Next I pulled the fuse for the cooling flaps when the engine was off so the flaps stayed open. Last, I put a 75c Wahler Thermostat in with a new water pump and timing belt... FIXED. car does not exceed 1/2 temp. Worth a try....
#58
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fwiw, I'm still at a suspected final output failure in my mind, since there is no definitive and direct test of the amplifier output. But I have no voltage at one of the fan wiring terminals and continuity between the terminal and the round plug pins of the amplifier, and I seemed to have passed the diagnostic tests of the fan controller, so... gettin' close now! The amplifier is gettign pulled and sent to Greg Brown.