Flex Fan vs Clutch

[bajajoaquin]

I put up the same summary about my '67 Imperial over on the Imperial group. One guy replied that some of the noise I was describing might be from a frozen fan clutch, which would cause it to rev up and get loud.

When I popped the hood to look, I found I had no clutch! Instead it's a flexible blade fan. And when the engine was revved up to check carb stuff, sure enough, I could hear that the sound was the fan.

Should this application have a clutch? Is there an advantage of one over the other?

 

[Big_John]

That's most likely an aftermarket fan and my advice is to lose it and put a factory fan and clutch in.

I personally witnessed a flex fan coming apart and going through a hood of a big block Chevy Nova. Then a local guy was killed when one came apart as he tuning his car.

I've seen some factory flex fans on later cars that are most likely OK... but the aftermarket stuff needs to be tossed.

 

[bajajoaquin]

So after some poking around, I'm having a tough time finding an original fan. FSM shows a 4-blade fan. If I search for '67 Chrysler (or Imperial) at NAPA, I don't get any fans, only generic 5-blade fans (or more). What's a good source for an original fan?

 

[MrMoparCHP]

So after some poking around, I'm having a tough time finding an original fan. FSM shows a 4-blade fan. If I search for '67 Chrysler (or Imperial) at NAPA, I don't get any fans, only generic 5-blade fans (or more). What's a good source for an original fan?

Ebay, wrecking yards, Mopar swap meets.

Not a great picture...

Just about any mopar fan will work, just get the spacer and check clearances befor running.

Alan

 

[bajajoaquin]

Are they all the same, or do I need to find one for a 440?

 

[Big_John]

The fans should be the same, except a clutch fan has a larger bolt pattern.

 

[rush]

I pretty sure some fans are larger than others so if you have a shroud you should measure it before buying one.

 

[Big_John]

Classic Industries has some repop fans for use with a fan clutch. Price looks good and you just need to pickup a new clutch that should be available almost anywhere.

 

[Big_John]

I pretty sure some fans are larger than others so if you have a shroud you should measure it before buying one.

You're right... I was just thinking bolt pattern.

 

[Mr C]

Hmmm. Imperials almost always had A/C and the clutch fan. I also find it hard to believe the FSM calls for a 4 blade fan for the Imperial. Definitely ditch the flex fan. My 74 Imperial runs a 7 blade clutch fan.

Is your FSM an Imperial FSM?

 

[53ryder]

So I'm ignorant. What is the purpose of a 'clutch' when talking about a fan? To engage the fan slowly as the engine speeds up?


Glenn

 

[jake]

The fans should be the same, except a clutch fan has a larger bolt pattern.

I thougth that an A/c car had 5 blades and non a/c had 4?

 

[goodneighbour]

So I'm ignorant. What is the purpose of a 'clutch' when talking about a fan? To engage the fan slowly as the engine speeds up?


Glenn

The spring on the front of the clutch senses the heat, the more heat the faster it spins. Cooler it spins slower.

 

[bajajoaquin]

Hmmm. Imperials almost always had A/C and the clutch fan. I also find it hard to believe the FSM calls for a 4 blade fan for the Imperial. Definitely ditch the flex fan. My 74 Imperial runs a 7 blade clutch fan.

Is your FSM an Imperial FSM?

It is an Imperial manual, yes. But it's for Chrysler and Imperial, so it may be showing the more common design on Chryslers. I'll put out a note on the Imperial group to see if anyone with a '67 can show an original fan. Maybe Matt can tell us what he has.

Someone on the Imperial forum said that he got a replacement at O'Reilley's for $40. I might check that out in the afternoon.

 

[Mr C]

It appears even the non A/C Imperial engines had a 7 blade fan...albeit without the clutch.

 

[detmatt]

Here's the best pic I have but mine's a non a.c. Car. I have my Imp service manual, I'll check it when I get to the shop today.

 

[Mr C]

There you have it...7 blade. Clutch with A/C...no clutch for non-A/C.

 

[detmatt]

Here you go, good info in the manual, you have a different one?

 

[commando1]

Gee, Matt. You're supposed to cut the page out and lay it flat on the scanner. LMAO.

 

[detmatt]

The tablet is just too easy!