Not sure if Fan Clutch is working.....
 

On a warm day of 70 degrees, the temp gauge goes 1/3 up, but if it gets any hotter, as soon as I stop, the car starts to heat up and the only way I can cool it down is either to shut it off or drive fast maintaining a constant speed. Is there some way to test whether the clutch is bad? Mine spins freely when the engine is off, but sometimes when I start it, it does the tornado spin for a few seconds and then slows down. Also, what are my options in terms of replacing the fan clutch and electric fans? What's the best one to get? TIA!

Try to flush your coolant. My friend had a protege and it did the exact same thing. We flushed his coolant, and it went back to normal

Sounds like it is the fan clutch. It shouldn't spin freely. If pushed by hand, it should stop almost within one revolution.

Replacing it with a junkyard one is the cheapest and fastest solution.

Electric fans are great, but take longer to install, cost more, need thermostats,

E-fans also release a few HP, which doesn't hurt either.
BUT, they also rob precious amperage from a stock alternator.

Depends on what you really want. If you're trying to squeeze every last HP out of your car, than E-Fan is the way. If not, just replace the fan clutch.

That isn't exactly true. If you look in a manual, the fan clutch is supposed to spin the fan no faster then 1400rpm as engine rpm goes past 1400rpm. My fan has always moved freely if you spin it by hand after its been run, and I don't have overheating problems...

When you intially start the car, the clutch sticks for a little bit matching engine rpm till the clutch is warmed up(usually 5seconds about). When its really hot out, it will clutch up the speed to match a slightly higher rpm(you'll hear a little more wind from the fan), but not really any higher then 3000rpm when really hot air is coming from the radiator and absorbed by the clutching.

A fan clutch that allways matches engine rpm is broken and will draw lots of hp as you rev it higher, not to mentenion hard on the water pump and belts...it will even sqeal the belt with normal tension. A properily working fan clutch will keep it under or at 1/2mark in traffic and will not draw enough HP to justify a electric fan. Afterall, most people using them find they don't cool any better and hp gains are NOT noticable.....

I have heard this testimonal from several 2nd gen owners that the stock fan is actually best and doesn't hurt hp more then <1-2hp.

If you are having warmer then 1/2 temps, you may need a new thermostat or SLIGHTLY cooler one unless its over 100F, you may get up to 2/3-3/4 on the gauge. I think stock thermo is 180F. I use a 170F one and it actually runs too cool much of the time(below 1/3 on the gauge).

:cool:

Okay, the coolant has been flushed and the 180 degree thermostat is in. Also, the fan clutch does not sound louder at all on hotter days. Lately, it hasn't been sticking at startup. And if I find a fan at a junk yard, how can I tell it it's working, not too free spinning, but not frozen? Let me know, TIA.

Okay, let me Clarify:
WHEN COLD, It shouldn't spin freely.

From the MAZDA SERVICE MANUAL.

https://www.rx7club.com/forum/attach...&postid=757844

Oh, I forgot to mention, when it has not been spun for a while and you spin it by hand it will not turn freely. If you continue to spin it, it will start to turn pretty freely...which is normal...all ones I have incountered do that. Seems like the '84-85 fan clutches are better, but requires drilling the holes on the connector to the water pump to make them fit properly.

Okay, I'll try to get one from the junkyard. Also, when the air conditioning is on, I can hear the fan spin faster as soon as it's turned on. Is this normal?

That's just the idle adjusting for the Air Conditioner.
Our cars have an idle adjustment valve that kicks in when you turn on the A/C for the added load.

Perfectly Normal. - At least yours is working.

Okay, thanks for letting me know. It gets really loud and when I rev the car up when the air is on, it sounds like a jet! It sounds cool, but it takes a lot of power away.