Bs, you know better than that. I am going to bed . Talk to you guys tomorrow.

 

I am experienced with heavy trucks, these vehicles utilize an air opperated clutch hooked to a fan that moves a bunch of air. Sometimes these will malfunction and stick in the "on" position, when this happens, the mileage will drop from about 7 mpg to about 6 mpg as compared to when the fan cycles normally.

The real advantage I see with the clutch fan is that a person can run a fan that movesmassive quantitiesof air when it is on, helping to cool the engine quickly, then cycles off when not needed to save energy/hp.

I am sure everyone has heard these fans (on trucks) cycle on and off going down the road, they make one hell of a racket, but they are capable of droping the water temperture 30 degrees in about 15 seconds, even in very hot and demanding conditions.

Likewise, if Ihad a vehicle subject to overheating,I would want to use a clutch with as big a fan as practical hooked to it. A fixed fan movinga like amount of air would be an energy waster most of the time, andI don't think that an electric fan with a similar capacity is available.

I am not saying that a fixed / flex / electric fanis no good, in fact they are very good for their intended purpose, and regular use, butconsidering the position that this op is in, I think that the clutch fan is the best solution, or at least worthy atempt to fix the situation.

 

,,,,,

 

In your case - yes. A flex fan has no moving parts, it flexes to achieve cooling at different speeds. A clutch fan has moving internal parts and fits my premise of more possibility of failure. I didn't say when, but like you say, they seize.
Jim

 

i have a flex-a-lite fan, a four core radiatior and i use redline water wetter with a 180* thermostat.
i do not have a shroud and my car will not get higher than 190* on a hot day!

 

Ok,,, I have lots of vehicles with clutch fans, ie: big domestics, all combined their mileage would be in the millions, right now I can not recall one instance where I have replaced a fan clutch in any of them, (excluding heavy trucks).

I have both Ford and GM products with clutch fans, they are very reliable,,,, or maybe I am just lucky that way?

Like I have said, I have nothing against flex fans, but the clutch fan may allow people with marginal overheat issues to overcome their problem.

If I were going to run a mechanical fan, and I still might, I would start with a flex, and then move to a clutch fan if it would not keep the engine cool. I like the lack of bulk that a flex fan offers.

 

James (JMD), I agree with you. I've had both and never had a problem with either. In my two current non-Hi-Po cars, I've got five blade Ford fans, shrouds and three core radiators. It works for me. The only thing I can say about clutch fan failures is hear-say, no first hand information.
Jim

 

my neighbors 1995 ford clutch fan just went out. i'd say it lasted a while.

 

A fan clutch, like any part, if treated properly will last a while(ie not bashing it with a hammer to get it off, prying on it etc), but a flex fan has better reliability because of no moving parts. A fan clutch will EVENTUALLY fail(even if it takes 10 million miles) a flex fan(if it's good quality) will take a LOT longer to break, and basically as long as it doesn't rust is gonna last forever. A clutch fan most likely works better, but is also more expensive and more bulky, and less reliable(though still very reliable). It's a tradeoff, like EVERYTHING with a car, there is no magic bullet part, everything has it's own advantages and disadvantages