85 FB

So, I just took off my plastic fan with fan clutch off. More than likely, it's the original and needs to be replaced but I'll still ask.

How can I tell if my fan clutch needs replacing? How much resistance should I feel when holding one part of it and turning the other? Right now, you do need to put some slight effort into it, it surely does not spin freely or with the minimal flick of the wrist.

bliffle

Sounds OK to me. The only one I've ever replaced was because it was binding.

85 FB

Well, I decided to look up how much one would cost me and holy Hell, that's expensive. $180 from AutoZone. Now, I see why more people prefer electric fans. A lot cheaper.

RXnos1200

iTrader: (24)

Is the fan spinning when you turn off the engine after is has reached running temperature?
Is your 7 running hot when driving or idling?

JWteknix

iTrader: (2)

i have 2 working ones off a tII if you need one

85 FB

My car's temp needle does not move past 1/4 (barely touches the Temp. gauge picture). The fan stops spinning when the engine shuts off. No overheating from what I can tell, and as usual, if it's really cold outside and I have the heater on full blast (3 or 4 speed), the needle is a bit further away from the gauge icon.

I'm just curious if this thing will need replacing soon. Car's always idled fine and that needle has never moved past that 1/4 mark, even during spirited runs.

RXnos1200

iTrader: (24)

Ok so why do you think you need a fan clutch? Seems like your car is running good. So that's a good thing.

85 FB

As I said, I was not sure if it'll be needing replacing soon or not. I don't know how much resistance it should have before it finally locks up and is always spinning, putting drag on the motor.

RXnos1200

iTrader: (24)

Not sure how you would measure the resistance of the fan clutch when it is hot or cold. I've never heard of it being done. Just pretty much check by hand I guess just like you have done. Seems like you're good to go though.

bliffle

I have 4 rotaries running, and have been driving them for 24 years and the only problem with the OEM fan was one fan that the clutch was dragging on somewhat, so finally after many years I replaced it because it was annoying hearing the fan whirring when I accelerated. Then, I replaced it with a fan assembly from the JY that I paid $10 for and it's been working fine for 2 years.

Unless you have a known problem you are worrying for nothing. And if you ever DO wear out an OEM fan you can get one at the JY for paltry dollars, and/or you can get one cheap or free right here at the rx7club. The last place I'd look for a fan would be at autozone. If you're worried that much about it just get a spare right now, either at the JY or from someone in the club. I used to have a spare and I finally threw it out because even with 4 vehicles I couldn't imagine I'd ever need the damn thing. For one thing, at 40-50mph you don't need the fan, and for another you could jimmy the fan to stay on long enough to make it home in slow city traffic.

The biggest threat to your engine overheating is not fan failure but heater hose failure. That hose going under the beehive gets soaked with oil and eventually bursts dumping all your coolant on the road. Replace it NOW if you don't know its history. And every 50k thereafter. I say that because I had one burst after 80k, tho usually they'll go to about 100k. The mass of the RX-7 engine is very low so it will overheat very fast, and unlike heavier engines it is intolerant of overheating. You can replace it with generic 5/8 hose if you are ingenious and very patient, I've done it, but it's much easier to do with the $42 pre-warped hose from mazdatrix, but it's not very easy in either case, so it's best done in advance and at home.

On the other hand, if you install an electric fan you can expect to have problems getting it to work right, what with temp sensors, shrouds, and even deciding which fan to use. There have been many more posts over the years about electric fan problems than about OEM fan problems. And that doesn't even solve the real threat, which is that !$#@#$ heater hose!

Rx-7Doctor

iTrader: (13)

85Fb, the rule of thumb on our fan clutches is this. When the motor is at operating temp there should be resistance in the fan clutch where it would not spin around more than maybe 1 turn.
When the motor is cold the fan clutch should spin a few times by hand before it stops. This is every other spin. If it is cold and you spin it, then it will go around a few times. The next time you spin it, then it will have more resistance. If the fan clutch has alot of resistance in it when the motor is cold then it is going bad. What will this do the motor? Make it run too cold, lose gas mileage and wear out the water pump bearing faster.

85 FB

That last part, of it being cold, I believe that is how my fan clutch is going. It feels slightly too stiff to be still in good condition.

bliffle - What is "JY" ? And, I have a GSL-SE, so no beehive oil cooler. And, I am not worrying, just curious. Because I know that if this clutch wouldn't turn at all, or really required some effort, I wouldn't be posting this question on the forum but making plans to get a replacement of some sort. Which, I hope doesn't turn into that, because I can't really afford it right now.

Rx-7Doctor

iTrader: (13)

"JY" = Junk yard.

85 FB

^ Thanks.

Yet, the junkyards around me don't have squat. Altho, there is a guy with a ton of 1st Gen stuff that I could easily get a replacement. *L*