-
Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.
what rpm does the clutch fan shut off at?
- Thread starter skog
- Start date
Rev Den
NAXJA Forum User
- Location
- Plainfield, IL
When its cold.
As the clutch warms it grabs.
Rev
As the clutch warms it grabs.
Rev
Unless you have one that malfuntioning. My old one was so damn loud on the hwy when the a/c compressor kicked on. It was loud till you got over 65 and then you didnt hear it anymore. I've never heard of anything like that but it did it. I still dont understand why the a/c compressor engaging had anything to do with it. I had a long thread about it a while back and no one could really explain it.
It was a Carquest POS, way overpriced fan clutch. Avoid them, they suck. I got an OEM one and it works a lot better and is silent on the hwy like it should be. I only hear it roar on when i first start it up and when it hot and I'm in traffic.
It was a Carquest POS, way overpriced fan clutch. Avoid them, they suck. I got an OEM one and it works a lot better and is silent on the hwy like it should be. I only hear it roar on when i first start it up and when it hot and I'm in traffic.
MaXJohnson
NAXJA Forum User
- Location
- The Kansas Rockies
Atl XJ said:
The mechanical is fan is controlled in two ways. It has a thermal switch that engages (progressively, I think) when the underhood air temp rises and a viscous clutch that allows it to slip at higher RPM.
I can think of two reasons why it might appear to be influenced by the compressor clutch. When the compressor clutch engages, the air conditioning cycle is triggered. This pumps heat into the condenser in front of the radiator which would increase the air temp hitting the mechanical fan. The increased air temp would would work on the fan's thermal switch, helping to promote increased fan activity and therefore a higher noise level. The compressor also triggers the aux fan and while that has nothing to do with the mechanical fan, it would add to the percieved fan noise level.
Its not the electric fan. I was 99% sure it wasnt but just to verify it I unplugged the electric fan and went for a ride and it still did it. Also, it never gets/got hot enough on the hwy where it should engage. It also was instantaneously engaging on and off with the a/c compressor. I even bought that serpentine tension gauge from Napa that everyone recommends and the belt tension was correct. I took the first one back and got a new one and it did the same thing. I got fed up and shelled out the $100 for a new OEM one and it stopped the problem. I'd never heard of anything like this, I was stumped.
I've since been told by quite a few people that Carquest fan clutches have very poor quality control and many are defective right out of the box. It pissed me off since it was almost as expensive as the OEM one. I got it because I'd heard on here that it was one of the few aftermarket ones that fit properly.
I've since been told by quite a few people that Carquest fan clutches have very poor quality control and many are defective right out of the box. It pissed me off since it was almost as expensive as the OEM one. I got it because I'd heard on here that it was one of the few aftermarket ones that fit properly.
5-90
NAXJA Forum User
- Location
- Hammerspace
I usually use Hayden thermal clutches. They're just a touch longer than OEMR - but you can unbolt the upper crossmember, and the inch or so of lean you get is enough to clear the studs. As long as your motor mounts are in good shape, so are you.
I can see how the idea of the thing would be misleading - calling it a "fan clutch" seems to forget that it's a variable viscous coupling, controlled by temperature. I'm planning on getting rid of the thing anyhow - I don't mind the noise (it's a work truck anyhow) and while it's true you'll lose a little power from it running all the time, it won't be enough to be a problem (you probably won't even notice if you just check with the Butt Dyno.)
Bear in mind they're good for about five years - I tend to sign and date them when I put them in (engravers are so nice...)
5-90
I can see how the idea of the thing would be misleading - calling it a "fan clutch" seems to forget that it's a variable viscous coupling, controlled by temperature. I'm planning on getting rid of the thing anyhow - I don't mind the noise (it's a work truck anyhow) and while it's true you'll lose a little power from it running all the time, it won't be enough to be a problem (you probably won't even notice if you just check with the Butt Dyno.)
Bear in mind they're good for about five years - I tend to sign and date them when I put them in (engravers are so nice...)
5-90
