I am considering putting an electric radiator cooling fan on my Scamp when I get the engine back in the car. I am guessing I need to power the fan through a temp switch.

Where is the best place to put a temp switch?

Are there any other complexities such as safety or fail safe circuitry I should consider?

Also I am considering a JY electric fan if I can find one. Any suggestions on types and sizes?

Thanks

If you put the fan on the back side of the rad, the fan must be no thicker than 3.5" if you center the fan. Otherwise the electric motor interferes with the water pump spindle and pulley. Also, you will switch your fan with a temp switch which will mount to the back of the radiator, and this switch should turn a relay on to power the fan. The relay will serve to shield the ignition from feed back from the fan motor, which is "noisy'electrically. Also, when the fan is coasting to a stop, it will function as a generator. If you have an electronic ignition, the coasting, spinning fan will generate enough power to provide spark from your electronic ignition, and the engine will not shut down immediately when you turn the key off. The relay serves to isolate the fan motor so that this does not happen. It is worth the hassle. It will free up RPM's at the upper limits of a slant. You will need about 2000 CFM's to cool the engine on a hot day sitting in traffic..

Pay attention to the actual motor on electric fans as your wandering through the yard, too. You'll notice that there is a difference. There is the typical 12vdc motor, that looks like a heater blower motor, just being used in a different manner. But.....there's also what's termed as a "pancake" motor. It's larger in diameter, but about half as long, (front-to-back), as the others. This ought to allow a bit more clearance where you need it.

You could also think about a pusher instead of a puller configuration.

Roger

Is the temp switch an air temp or coolant temp switch?
I have AC so a pusher might not fit in front but I'll look.
Also I assume the relay coil power should be tied to switched power. I take it the fan should never run if the car is off. Is this correct? Because every once in a while I hear someones fan running in a parking lot after the car has been shut down.

Thanks

Since you have A/C, you must wire the electric fan to run any time the A/C compressor is running, even if the engine is cold. As for the fan running with the engine off. Depending on how it is wired, this is possible. As you noticed, some OEM setups do this. It is due to "hot soak", and should only last for a few minutes.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

If you can find a Fiero in a JY you have found a pancake fan. you can get a temp switch/relay at any auto parts store. I got one with an adjustable thermostat at National Auto for $23. All you need to do is attach the sensor to the rad, run one wire to the fan(and a ground from the fan), and the other to a 20Amp switched source on the fuse block.

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An electric fan is a good idea, but there are a few things you should watch...

Most modern cars equipped with electric fans also use more efficient aluminum radiators. So what works as a fan/radiator package might not work with your copper/brass radiator. The Flex-A-Lite black magic fan I use on my 1980 Aspen was marginal with the OEM one row radiator, but did improve significantly with my current replacement two row Modine.

The current draw on some electric fans is significant and might exceed the output of your alternator. You might need to install a higher output alternator. If you do this, you should also add a parallel circuit of heavy gauge cable from your alternator to your battery. Run a fuse in the main power circuit to your fan.

Depending on several factors which includes the design of the fan you ultimately use, you might need to fabricate some kind of air foil or spoiler to attach to the lower radiator cross brace. This will prevent air once drawn through the radiator and heated from looping back and being drawn through again.

Good luck.

Mitch

As long as you have a 60 amp alt or better you should be fine. If you go with an aftermarket fan they should take about 25 amps. This will create a drain when idling if you have everything on, but it can handle the load when driving. You can wire it to run after the car's stopped, but at 25 amps I think that's too much risk. Normal sized fans will fit if you don't mind the fan being a little off center, and you should get one sized for a V-8, or bigger. The electric fan is a fairly easy install, but if you do it wrong you don't want to be driving around not knowing it. Stick an indicator light on after the fuse(so if the fuse blows you'll know it), this way if you did something badly and it stops working you won't find out by smoke coming out your engine. Also, they're are fans that are push/puller types, but make sure they you got to flip the fan and reverse the polarity, otherwise it's probably gibberish. Personally, I like the idea of an aftermarket radiator like MitchB was talking about, though I find my electic is more than enough as a puller fan on a stock radiator.

Sorry, above is me. Something about the draw of the fan, it'll only be in the 20 amps at starting, after starting it quickly uses less draw(you'll notice when you first turn it on the lights fade but quickly go back to normal).

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My car may be slow to sixty, but at least it's been reliably slow to sixty for more than thirty years.

that is a point I forgot to mention, I'm running a V8 volare 2 row rad(my old stocker gave up months before I switched to the electric fan) which I sure helps with the cooling as well as gives my off-center fan more rad to cover.

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