alconk

I have a question regarding my auxiliary fan on my 82. I had bought the low temp switch from CC and the fan is suppose to come on at 200 and shut off at 185. Well when I first start the car for the day my temp rises above 200 before the t-stat opens the the temp comes down to around 180. (running a 180 Robert Shaw) well during that time the aux. fan will come on but won't shut off even with it below the 185 temp. But if I shut the car off then start it back up the aux. fan does not come back on until the temp is reached . So for right now the fan switch is unplugged and my temp stays right at 180. Running a aluminum radiator. So is that switch defective?

oldalaskaman

sounds like you dont need it

74 LS4-454

I also have that switch, but not installed as of yet.....
But I am confused as to why your temp goes so high during your first start-up of the day. My 82 never sees 195, let alone 200 degrees at any time, and I also have a 180 degree stat.
Something doesn't seem right about this, apparently there is a difference between what the switch sees as below 185 and what the temp gauge reads, and or the coolant temp sensor senses to be below 185 degrees. I'll have to sleep on this one....

alconk

Well it's like a slow reacting t-stat is what I think.

oldalaskaman

some times t-stats have to cycle a few times , depending on weather new or not before they settle in and work reliably. my robert shaws in both my vettes did that

74 LS4-454

not trying to break anyones' stones.....but maybe I am missing something....of all the Vettes and F-Bodies, and others that I have owned, I have never, ever experienced any temp acting the way as described above. Whenever the temp would reach the "correct" operating range for a vehicle, the stat would then open and keep the temp in that specified range. With the exception of extremely hot days and in stop and go traffic, which would see the temp rise and hopefully get under control from the fans and more air moving through the radiator. That is why there are switches and flashes available for the computer controlled vehicles, so you could make adjustments, etc.. And a variety of ways to lower temps on pre computer vehicles.
I have never heard of a stat that would have to "cycle" a few times to operate correctly. And to be honest, I hope I never have a stat that works like that, if I did, it be changed out in no time......

Arkyvette

I have a "slow" stat in my 82. It hits 200 or a tad higher before watching it shoot down to 185 where it stays the rest of the time. Who knows if the sending unit, gauge or tstat is the slow culprit...but I will accept it in this car.

alconk

Exactly the way mine works. But in doing so that's when it triggers the aux. fan to come on when it really does not need it.

74 LS4-454

Mine has never reached 195 degrees, it has been close with some of the hot days we have had recently, and only in traffic. The PO had a friend of his who owns a radiator shop put a new radiator in the 82 before I purchased and it did have a 180 stat in there, but I changed it out anyway when I did my waterpump, as I wasn't sure what was in there. But my temp is always at 180 or slighty higher and that is where it stays.....

74 LS4-454

But you mentioned that it does this with the new CC aux fan switched installed. I would put the old switch back in and see how that reacts and go from there. If your happy with where your temp is operating and it's not overheating, then maybe you don't need the switch. As I mentioned I bought one fo the 82, and I may never install it.

alconk

Yes that is correct. I have the CC unit in there and the reason why is the factory 2 prong sensor failed and have never been able to find a replacement. As of now I have the switch unplugged but would like it to work like it's suppose to.

74 LS4-454

I hear what your saying.....but......if your temp is never going to reach the specified (stock) temp that the aux fan is supposed to come on, then it is a moot point. I still have the stock switch in mine and it has never come on to my knowledge, I have not been really concerned about it since I am happy with the temp it is running. Having already been through a hot summer last year and summer coming soon, I don't see the need to even be concerned with it. And if your temp is operating where you feel it needs to be and you are not overheating, etc., then I wouldn't even concern myself with that fan. If your temp rises above 200 degrees and above and stays there, then you have concerns with other parts of your cooling system, water pump, radiator, hoses, etc.

Arkyvette

Mine has never come on in driving either. I tested the fan when I had it out and boy does it move some air and pull some amps. I guess its there as an emergency device or if I had the ac working, it would probably make the air a bit cooler in town.

74 LS4-454

I have to look in the Shop Manual, and see what the parameter is for that aux fan to come on. I'm almost sure it is set not to operate until a high temp. And you know I can't remember for the life of me if it does come on when the AC is engaged....See, this what "old age" does to you....

oldalaskaman

just because you don't know something doesn't mean it doesn't exist, it just means you dont know it, not busting ***** either but there are very few absolutes.

74 LS4-454

can you explain your statement......what exactly do you mean????

alconk

I read the fan comes on at a alarming high temp of 238 deg. I did however drive my car without the mechanical fan and that aux. fan kept my temp around 180-190. Thought about just running the car that way but did put the fan back on.

oldalaskaman

I and others have converted to electric fans eliminating the mechanical without issue, its getting to be a reliable product

alconk

I actually like that idea but not in the position to invest with a dual electric fan assembly. How do you feel about just running the factory aux. fan as my primary cooling? I think it would be fine especially with a aluminum radiator.

qwank

if you run it on just the AUX fan I would install a relay on the circuit. the factory wiring doesn't use one.