97XJ2
NAXJA Forum User
- Location
- Wisconsin & the U.P.
A mechanical fan clutch is: Supposed to spin freely when cold, and not spin freely on a warm engine (therefore locking it up). Correct?
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Tell me if I got this right.
- Thread starter 97XJ2
- Start date
bigalpha
Moderator
- Location
- Tucson, AZ
If you've never replaced it, just go ahead and do so. You may think it's good. It's not.
97XJ2
NAXJA Forum User
- Location
- Wisconsin & the U.P.
Well I wasn't gonna say it, but I just put the one I speak of in on saturday. Didn't pay attention to what the old one did.
Kevinma255
NAXJA Forum User
- Location
- West Milford, nj
You are correct, cold = free... hot = tight
RichP
NAXJA Forum User
- Location
- Effort, Pa
Normally when they are cold, like first start in the morning, they will roar, thats the fluid being redistributed after it settled overnite, usually if they don't give you that roar for 15-30 seconds the clutch is bad. Once the fluid is spun around it gets quiet, then as it heats up it may get noisier, usually you don't notice it being inside and it normally won't do it just sitting there idling except on a hot day.
bigalpha
Moderator
- Location
- Tucson, AZ
One thing I noticed is my old (bad) clutch fan didn't really put out much air. When I replaced it with new, the new fan would blow massive air. It blew leaves around under the engine.
x2elite
NAXJA Forum User
- Location
- Texarkana, AR/TX
bigalpha
Moderator
- Location
- Tucson, AZ
Rick Anderson
NAXJA Forum User
- Location
- Lusby, MD
I've replaced the thermal fan clutch on my Jeep, I can tell you a good fan clutch is NOT free moving cold, there is a noticeable amount of resistance, it will NOT spin freely if you push it, the moment you remove your hand it will stop.
When hot, the bi-metal spring on the front turns a valve that tightens up the clutch resistance even more.
So yes, you could say it should spin "more" freely cold than warm, but a better way to say it, is it should spin with greater resistance when warm than cold.
When hot, the bi-metal spring on the front turns a valve that tightens up the clutch resistance even more.
So yes, you could say it should spin "more" freely cold than warm, but a better way to say it, is it should spin with greater resistance when warm than cold.
98XJSport
Destiny is the rising sun
- Location
- Western Maine
I noticed a bad fan clutch not on startup, but on shutdown.
Think about any time you have shut off your jeep, and popped the hood. Ever see the mechanical fan still spinning? It was on my old clutch.
Think about any time you have shut off your jeep, and popped the hood. Ever see the mechanical fan still spinning? It was on my old clutch.
Jeepsr4me
NAXJA Forum User
- Location
- Mobile, Al
On a cold fan you should not get more than 2 spins when don by hand. When hot it should not spin more than a few times after shut down.