Busted fan and radiator, why did this happen?

[Dino]

So of all the things that could go wrong installing a thermoquad, this was not on my radar!

After a lot of time, I started the rebuild somewhere last winter, I finally had the whole thing done.  All linkages adjusted and fixed, some were seriously out of whack.  I bolted it to the Edelbrock performer intake with the spread bore 1/4" gasket provided with the rebuild kit.  I found another throttle cable bracket in a box and was able to install the throttle linkage so the gas pedal is now smooth without any slop, finally!

I was ready to fire this thing up and had 2 fire extinguishers next to me, just in case.  My wife was a safe distance away keeping an eye on this.  With a blocked heat crossover and no choke I knew I had to play with the gas pedal a bit and after a bit of cranking it fired up.  I stalled a few times so I gave it a bit more gas.  Now the idle was smooth in the 1500 range so I kept it there for a bit.  Rpm is a guess, I have no tach. 

Then the fun part came...I gave it two taps of 1/4 to 1/2 throttle, and we both heard a bang and some metallic clatter.  As soon as I let of the gas, the car died so I shut it off and walked to the front.  One of the fan blades had snapped off when I gave it a push, hit the blade next to it and pierced the radiator.   

So much for tuning the TQ...   

My radiator is out of a c body and had no shroud so I guess now is the time to stick a Charger rad in there and since I'll have some room to play, do some other small projects.  I'm not bothered by this really, shit happens, but I do like to know why this happened so I can prevent it from happening again.

So what kinda fan do I need?  '71 440 hp.

On a positive note, the car didn't burn down and the carb at least works.   

[Dino]

more

[JB400]

That happens with those types of fans.  The stock cars run those as well and some have the same results as what happened to yours.  It has happened to one of my uncles and wiped out his radiator as well.


Put the stock one back on with the fan clutch, or step up to an electric one.

[green69rt]

I keep sticking my nose in your project don't I??  Is that an old flexalite fan, plastic blades??  Back when I was rodding my first car I had heard of more than one occasion where an old fan lost a blade because the plastic got brittle and came off.  Maybe just bad karma on your part .  Good thing someone didn't have their head under the hood

[68Charger4me]

If that's one of those "flex" fans, they have a notorious rep for doing that very thing.  Happy you're still in one piece!!    

[A383Wing]

yea..those little flex fans are junk..known for doing that all the time...as stated, good thing you were not leaning under the hood. That blade looks aluminum...bet it was cracked already

I recommend stock 6 or 7 blade fans, I have these on my cars

Bryan

[Big Sugar]

Consider yourself lucky, i remember seeing an episode of "EMERGENCY 911" where a guy showed up in emerg woth a slice thru his neck from ear to ear from a car fan blade breaking off .

Yeah those FlexFans are for Chevy owners ! Id stick with a Mopar unit and a fan shroud... Be thankfull you or your buddy wasnt standing under the heed revving the carb maunually.


Ron

[nvrbdn]

definately agree with all said here about the flex fan. had one snap on me while working on a car a few years back. i had just left from under the hood and hit the throttle when it snapped. lucky for me it went straight down and burried 3 inches into the ground.

[Dino]

Thanks guys, I'm very happy nobody was hurt!  I never knew about these types of fans, it was on the car when I got it.  Which fan/rad/shroud do you guys recommend?  Near daily driven 440.

Oh and by all means green, stick your nose in my projects or nothing will ever get done on my part!   

[A383Wing]

If you have 26" radiator, I would use stock fan shroud, and non-thermal fan clutch with 6 or 7 blade fan....as I posted above. If you use a fixed fan without clutch, you are gonna get a lot of fan noise while driving

Bryan

[RECHRGD]

When I got my car back in 1997 it had a flex fan on it.  I ran it for a couple of years with no problems.  I went to the Mopar clutch type after hearing about these potential failures.  However the clutch pack held the fan too far from the radiator to get much air flow happening.  I don't run a shroud (long story) and need the fan close to the rad..  I put the flex fan back on with a larger spacer to get it closer and have been running it now for many years with no problems.  I keep hoping that maybe there was just a bad run of them for a while and that I may be spared the same fate that others have seen.  I will keep checking it for any signs of metal fatigue.  You've got the right attitude, s..t happens......

[firefighter3931]

The aluminum blade flex fans are notorious for self destructing. 

I've used the stainless steel flex fans on many builds and never had one come apart.....i would have no issue using a stainless steel flex fan on any build. 



Ron

[ACUDANUT]

I agree with you all. Your radiator looks like it can be fixed easily.   Mine was completely torn up.

[cdr]

if you use a good fan & a thermal hd clutch it will work much better,you will have less parasitic horse power loss & get better gas mileage  
or good electric fans, i am using the electric fans 

[green69rt]

All the above sounds like good info.  The plastic and aluminum fans are suspect, not all fail but history was against you.  Do you want to go thru this again.   Figure it out!!

[SkiJogg]

I would go with the clutch fan its a good dependable setup

[bill440rt]

Like others have said, ditch the junk aluminum flex fan.
Stick with an original heavy duty 7-blade clutch fan. The part number is 2863216. It is 18-1/2" in diameter
There is a slightly smaller diameter 7-blade fan, part number 2863215. It is 18" in diameter.
Here's one from a quick search so you know what it looks like. The 216 fan looks nearly identical except for the diameter:

http://www.ebay.com/itm/Mopar-2863215-Clutch-Fan-Inked-Hemi-RT-Cuda-GTX-426-440-383-340-318-Charger-/140990627793?pt=Vintage_Car_Truck_Parts_Accessories&hash=item20d3b23fd1&vxp=mtr

You'll have to measure from the rad to water pump for the right height fan clutch, but I have the MP "4704" unit on my '68 with a 2+6" rad and no clearance issues.
Here is what that clutch looks like:
http://www.ebay.com/itm/NOS-Chrysler-fan-clutch-mopar-/261228471391?pt=Vintage_Car_Truck_Parts_Accessories&hash=item3cd26e245f&vxp=mtr

[fy469rtse]

I'm with Ron , stainless steel flex type rated to high rpm with a shroud , clutch or not , the radiator looks like can be repaired , now look for the thread to reinforce that drivers side engine mount, cheap fix, a couple of hi tens bolts, ever seen the damage when that engine mont breaks , shroud fan hoses etc

[A383Wing]

I bought the torque strap from Schumakers for the Daytona

Bryan

[flyinlow]

Aluminum has a much shorter flex life than steel. (One of the reasons airliners have a cycle limit)  Mopar steel or electric fans should do the job.

When you fix the cooling system, let us know how the TQ and the performer work.

[tan top]

arrghh ,  noooo , glad every one ok !!
 yeah flexi fans , like other guys have said are known to do that ,when you think what can or could happen with these , maybe they should stop making them .   i have one fitted to mine , second owner put it on back in 85 , its a flexolite i think  five blade , with stainless steel blades ,  put the correct 216 fan on after the resto swapped it on & off a few times , but seems to run slightly cooler with a flexi fan , when idling for long periods , not by much few degrees , prolly went up to 195 from 180 /185 degrees , ( although could most of it been cause i was messing around with idle mixture & speed & initial timing , to do with a particular cam i was running  ,)) main reason why its still on there , & i'm crazy about over thinking things   , the weight of a stock fan set up compared to the flexolite , thinking heavy stock fan more stress on water pump bearings ,
even though there have been hundreds of thousands of mopars over the last 44 plus years running these fan set ups & none have shortened the average water pump bearing life , unless mythbusters want to do a experiment running a stock clutch fan & a flexolite fan on two identical 440s with same fan belt tension for 50 thousand miles , then measure bearing play  

[cudaken]

 Yep, been there and done that! I was luck in the fact the radiator was not hurt. I now use a steel fan and clutch.

Cuda Ken

[Dino]

Thanks again for all the comments.

Seems to me that the price of a recore is in the $300-$500 range which I think is kinda high to recore a rad that's wrong for the car.  I may as well buy a new repro one right?  Which one is recommended?

I can do an aftermarket aluminum but I need it to fit without mods so preference at this time is to stay with the stock setup.  


Would there be any reason to replace the water pump?  I realize all this stuff is old but the car can sit idling in traffic in 90+ degree weather for as long as I want it to and it never gets too hot.  For that reason I don't want to mess with it too much but I thought I'd ask.

Bill thanks for the links, I'll get those parts as well.

[Dino]

Does anyone know how many rows the 3443953 rad has?  The repro rad is a 3 row with 1/2" tubes on 9/16" centers and I just want to make sure it'll cool enough.

This is turning out to be quite the expensive little accident!

I like the Griffin rads and all but this is a driver, when the hood goes up it means something is wrong so I just need a basic rad that'll do the job.

[Cooter]

Yep, Dino, this is why I do NOT like Mechanical fans at high RPM. Especially, the "Flex" fans. Glad you weren't hurt buddy.

[bill440rt]

Thanks again for all the comments.

Bill thanks for the links, I'll get those parts as well.

Don't go out & buy a clutch just yet, Dino. Wait until you get the radiator and you know how much clearance you have. 
With a 26" rad and a clutch fan you might need a "short shaft" clutch. The MP 4704 units have just a slightly longer stem which places it closer to the rad.
The fan clutch is about 3/4" or so away from the rad in my '68. Core thickness is the same as stock. Tight, but it does clear. It's been on there for a while with no issues. I have a short shaft clutch that I'll be swapping in soon for peace of mind, though.
The Griffin rads are VERY nice, but thicker than stock so the 4704 clutch would not fit in my '69 so I went with electric fans.

[ws23rt]

I feel the need to add two more cents to this topic. If there is too little clearance between the fan and the radiator than the risk of damage from a small front end  hit is high. The engine mounts flex and I have had radiator damage from a rather small impact. 3/4 in should be good enough with motor mounts firm.
I have also seen a curved slot in a hood where a fan blade came through.

[ACUDANUT]

When my fan ate my radiator it was from a worn out Bushing in the water pump. My 70 Charger has 4.11 ( ? ) rear gears and at highway speeds, it rev's at over 4K RPM's at 60 miles per hour. It's a 1963, 426 wedge 4-speed.

[Dino]

Alright, the radiator is being repaired so I'm keeping it.  It's the '71 c body rad and I would like to know if these are the same thicknes as the '69 b body rads.  Which thermal clutch is recommended to ensure I have plenty space away from the radiator so I can fit the shroud I have yet to find?  

Is there a clutch/fan kit available at local parts stores?  Don't care for originallity but I would like to get something good.

This is for an a/c car btw.

[Cooter]

Will offer one more tidbit of info. here. A word of caution. Never try and run a "junkyard" fan clutch. I did and the same thing happened. Clutch was who knows how old, and bushing or something was worn, when the R's hit real high, tink,tink,tink,scrape! Not good ona like new radiator. Sucked big time.

Yes, Dino, Parts stores will have some fan clutches, but you need to wait till you have measured the clearance to your radiator core as you might need a Clutch which is very shallow.

[Dino]

Ah good to know junkyard fan is not an option as I thought it was.   

I dropped off my radiator last night at a small rad shop that has been in town for near 50 years.  Today I get a call just before I leave work that it's ready to pick up.  They brazed the gash, cleaned the entire thing in and out and repainted it, all for the whopping sum of $45!  I had no idea people did anything for that amount anymore!   

I'll drop the rad in tomorrow and post the measurement.

[Cooter]

Careful Dino....Not to worry you, but I too have radiators "Repaired" that way, and you wouldn't believe how many times I've seen the tubes completely soldered shut. Will it leak? No, but that's not the point. I could take out all the cores that are damaged and it won't leak, but it won't cool properly either.

Since your shop has been around for years, hopefully, they are better at repairs than the older gentleman that everybody yhere said was a "Wizzard" with radiators...I ended up buying a new one.

[Dino]

Careful Dino....Not to worry you, but I too have radiators "Repaired" that way, and you wouldn't believe how many times I've seen the tubes completely soldered shut. Will it leak? No, but that's not the point. I could take out all the cores that are damaged and it won't leak, but it won't cool properly either.

Since your shop has been around for years, hopefully, they are better at repairs than the older gentleman that everybody yhere said was a "Wizzard" with radiators...I ended up buying a new one.

I had the exact same concern but when I removed the rad from the car and stuck a hose in it, the stream coming out the gash was surprisingly small.  The gash was about 3/8" long and right on the edge of two tubes.  I know how to weld but have only brazed once and it didn't look all that bad all of a sudden.  Once I saw this nice, smooth braze I was content, I think it'll be fine.  I'll keep a good eye on the temp gauge though, not to worry.

Oh and I looked into the rad and it has a three row core so I guess it's thicker than the 055?

What distance would the actual fan have to be from the rad to make a stock shroud work?  That is assuming I can find one...

[Cooter]

What distance would the actual fan have to be from the rad to make a stock shroud work?  That is assuming I can find one...

I like to give even the Clutch fans a little "Wiggle room" to move around. (The blades will move a little under max cooling when clutch is locked)
I like to see anywhere from around 3/4"-1". No more than that from the core as the clutch needs Heat in order to work properly. I've seen fan clutches as far as 2 1/4" from the core, and worked ok.

You need to make sure you have at least 3/4" clearance from the core. Shroud can be made to fit from other cars like Fords, if you cannot find the correct one at a junkyard.. I'm running an old Ford LTD shroud on the GL and works fine. All it does is direct air flow.

[bill440rt]

Dino, do you know the thickness of the core? Mine is a 3-row as well. Do you know the numbers off the top of the rad?

"IF" you can find a new, unused TRW FC-28 clutch then snag it. They have been disco'd for a while, but sometimes you might get lucky at an older parts store. They are identical to the original Mopar short-shaft units which have been long out of production. The "4704" clutch superceded these units. The stem is a little longer but will clear the rad by 3/4" or so.
Personally I'm not a fan of the Jaguar units that some people use, as from what I've heard the mount on the water pump is not wide enough to clear the mount bolts fully so washers are needed.

Put the rad in the car, take a measurement from the water pump mounting face to the radiator core. Let us know the measurements. 

[Dino]

Dino, do you know the thickness of the core? Mine is a 3-row as well. Do you know the numbers off the top of the rad?

"IF" you can find a new, unused TRW FC-28 clutch then snag it. They have been disco'd for a while, but sometimes you might get lucky at an older parts store. They are identical to the original Mopar short-shaft units which have been long out of production. The "4704" clutch superceded these units. The stem is a little longer but will clear the rad by 3/4" or so.
Personally I'm not a fan of the Jaguar units that some people use, as from what I've heard the mount on the water pump is not wide enough to clear the mount bolts fully so washers are needed.

Put the rad in the car, take a measurement from the water pump mounting face to the radiator core. Let us know the measurements. 

Thanks Bill, I'll check for that clutch, I do have a store or two with old stock around.

The radiator # is 3443953 off of a '71 c-body.

A member here has the MP vicious kit for sale I am interested in, just need to make sure I have plenty clearance.

Measurement to follow!

[Dino]

The gap between rad and the grey thing is about 2" and about 3.5" to the pulley.

[bill440rt]

Dino, if you're going to run a clutch fan you'll have to ditch that spacer.
Looks like you have a pretty thick rad core, I can see the thickness at the bottom tank. The "4704" clutch might not be an option, it is 3-1/4" in height.
There was a guy on the '70 'site that had several FC-28 clutches (I think his I.D. is dealer demo?). That's where I got mine from. They are getting hard to find, too. You might want to try contacting him?
If I can get to my '68 over the weekend I will get some pics of the "4704" clutch/rad setup clearance in my car. 

Edit:
Yes, his handle is dealer demo. Read here:
http://www.1970chargerregistry.com/mboard/index.php?topic=1486.0

[Dino]

Spacer...I could've come up with that...but I didn't.   

Yeah I need this clutch at least 3/4" from the rad so the clutch can be no more than 2 3/4" thick.

So since I have a spacer, I have pretty long fan bolts, do the clutches typically come with bolts or do I need to get anything special?

I found one of the fc-28 clutches on ebay, but I just can't spend $400 on this.  $50 is more in line.

I'm assuming the MP vicious won't work here?

[bill440rt]

These are the fan bolts:
http://www.ebay.com/itm/64-74-Mopar-A-B-C-E-Body-Cuda-Dart-Road-Runner-Correct-Fan-Clutch-Pulley-Bolts-/400494340050?pt=Vintage_Car_Truck_Parts_Accessories&hash=item5d3f52a7d2&vxp=mtr

The seller of that fc28 clutch is known for prices into the stratosphere. You'd be better off looking elsewhere.
The MP viscous won't work, the clutch that comes with it is the longer 4704 unit, and the fan itself never clears the shroud at least in my experience with it.

[Dino]

These are the fan bolts:
http://www.ebay.com/itm/64-74-Mopar-A-B-C-E-Body-Cuda-Dart-Road-Runner-Correct-Fan-Clutch-Pulley-Bolts-/400494340050?pt=Vintage_Car_Truck_Parts_Accessories&hash=item5d3f52a7d2&vxp=mtr

The seller of that fc28 clutch is known for prices into the stratosphere. You'd be better off looking elsewhere.
The MP viscous won't work, the clutch that comes with it is the longer 4704 unit, and the fan itself never clears the shroud at least in my experience with it.

Hmm, what about that Hayden 2765 clutch?  Those are less than 3" I believe.  There's a small Carquest not far from me, in a small village.  They have loads of old stock so I'll check with them first to see what they have.   

[ACUDANUT]

I don't think you need a spacer with a viscous fan package.  Shrouds ? what shrouds I have never needing one. 

[A383Wing]

I got one of my fan clutches from Car Quest years ago

Bryan

[Back N Black]

These are the fan bolts:
http://www.ebay.com/itm/64-74-Mopar-A-B-C-E-Body-Cuda-Dart-Road-Runner-Correct-Fan-Clutch-Pulley-Bolts-/400494340050?pt=Vintage_Car_Truck_Parts_Accessories&hash=item5d3f52a7d2&vxp=mtr

The seller of that fc28 clutch is known for prices into the stratosphere. You'd be better off looking elsewhere.
The MP viscous won't work, the clutch that comes with it is the longer 4704 unit, and the fan itself never clears the shroud at least in my experience with it.

Hmm, what about that Hayden 2765 clutch?  Those are less than 3" I believe.  There's a small Carquest not far from me, in a small village.  They have loads of old stock so I'll check with them first to see what they have.   

i have the Hayden clutch with stock fan and no issues so far.

[Dino]

I'll have the Hayden clutch tonight and a Hayden 18" 6 blade fan tomorrow.  The guy at the store said the blades themselves are aluminum.  The hub is steel.  Of course I don't have to take it if I don't like it.  When I look at the fan on Summit it says I have to use a spacer but shouldn't it bolt up directly to the clutch without?  Should I not get this due to the blades being aluminum or will it be okay?

Not sure which of these it is...

http://www.summitracing.com/compare

[Cooter]

I'll have the Hayden clutch tonight and a Hayden 18" 6 blade fan tomorrow.  The guy at the store said the blades themselves are aluminum.  The hub is steel.  Of course I don't have to take it if I don't like it.  When I look at the fan on Summit it says I have to use a spacer but shouldn't it bolt up directly to the clutch without?  Should I not get this due to the blades being aluminum or will it be okay?

Not sure which of these it is...

http://www.summitracing.com/compare

Dino, No clutch fan will use a spacer unless it's in some oddball set up like trucks/vans/Industrial, etc. I think you'll be ok with the Hayden set up. I couldn't remember the name of it to save me.

[ACUDANUT]

Yep, clutch fan do not use spacers.

[Hemidog]

Dino, was it this 18" one you went for? http://www.summitracing.com/parts/hda-3618

Let me know what you decide, I'm trying to find a original all-steel one, but it is not easy or cheap.

[tan top]

 have a look on the hayden site , gives all the dimentions on all their  fan clutches      

  http://www.haydenauto.com/upload/HaydenAuto/Documents/Cat_Hayden/2007-hayden-fan-clutch.pdf

[Dino]

Dino, was it this 18" one you went for? http://www.summitracing.com/parts/hda-3618

Let me know what you decide, I'm trying to find a original all-steel one, but it is not easy or cheap.

Yeah I think so.  The link I posted has that one and the 3620 and I think the 3618 is the one for mopars.  I'll have it tonight or tomorrow, depends when I get home.  I saw a few original ones but I'm wondering if it's wise to run a 40+ year old fan.  I sure hope this one doesn't blow up as well!

Thanks Tan!  That's good info to have. 

I'll keep you guys posted.  I'm also removing the old heater hose nipples from the wp housing so I can plug them until the heater and a/c controls are installed.  One came out easily, the other will need a few more gallons of pb blaster it seems.  The plugs I need are 3/8" right?

[bill440rt]

Dino, do you know the pitch on this Hayden fan?

The original 215/216 fans were steel. 

[Dino]

I have no clue Bill.  I would guess to say that the pitch is less than the stock fans seeing they don't recommend these for engines running 4000 rpm +.

Since my car is a cruiser and all I had before was this stupid flex fan without a shroud and no overheating issues, I don't think there will be a problem but we'll see.  So far I can't find anything online where someone had one of these fail so that's a start!  Besides, I can always swap the fan later if I come across one.

[ACUDANUT]

I don't think you need a spacer with a viscous fan package.  Shrouds ? what shrouds I have never needing one. 
[/quote

x2

[Hemidog]

Awaiting pictures of fan installed 

[Dino]

I installed the Hayden 2765 clutch and the 3816 fan and guess what, the damn fan hits the steering pump bolt.   

Now I have to go back out, get longer bolts and find a friggin' spacer! 

Getting the clutch on the hub with the fan installed is one of the most annoying jobs I have ever done!  What a pita!

[bill440rt]

What is the diameter of this Hayden fan, Dino?

[Dino]

False alarm.  I don't know what happened but when I removed the clutch and fan and reinstalled it, it cleared everything.  Whatever it was, it was my doing so we're good!   

The fan is 18" diameter Bill.  IT clears the power steering bolt and pulleys by roughly 1/2 - 5/8" and there is about an inch between clutch and radiator.  Haven't measured yet but I can stick my hand in between. 

Everything is back in place, coolant added and it runs again.  I need to tune the TQ but I'm happy to say it idles real nice, way better than the eddy so that's a good start.

Now all I need is a vacuum gauge so I can tune this thing.

[Hemidog]

Pictures! 

[Dino]

There is about 1 1/16" space between the radiator and clutch.  I'm not sure if a stock shroud will fit as I've never had one.  I can assume that in order to mount the shroud the fan or radiator needs to be removed or can it be maneuvered on without taking it all apart?

[Brightyellow69rtse]

looks great man! could you post exactly what you bought for me if you dont mind?  could you measure the total assembled length of it? meaning the distance from the mounting pointon the water pump to the face of the clutch meaning the closest part to the radiator?

i too have a flex fan that has been waiting to explode. i would rather get it before it gets me.

[A383Wing]

that's about the clearance I have on the dream 66 without a fan shroud...so far, no issues...looks like I got the same fan blade as well

Bryan

[Dino]

Sure thing.  Both clutch and fan are made by Hayden,  The fan is part number 3816 and is 18" in diameter.  Since Bill asked I'm going to see if I can figure out the pitch of the blades.  Note that the fan Is not recommended for use over 4000 rpm.  This doesn't mean the fan will shatter if you go over it as they need quite the buffer to cover their butts, but if you race your car I'd go with something else.  I usually stay under 3000 so it works for my application.

The clutch is part number 2765.  Both parts were available at my local parts store.

I was going to buy the Imperial 18" fan from advance auto but they were out and couldn't order more.

Oh and use grade 8 bolts.  Neither parts come with bolts although there are 4 split washers that come with the clutch. Clutch to pump uses 5/16 5/8" or 3/4" depending on the washers you use, I use a plain and a split washer wherever I can.  The fan to clutch bolts I used were 3/4" but had to use an extra washer.  That said I think a 1/2" bolt with only a split washer may be a bit short.  The threaded parts in the clutch are only 1/2" deep.  I was able to torque the bolts to specs and everything seems rock solid.  Now watch me eat my words when the fan goes through the hood on the first test drive...oh god that hurts just thinking about it.

[Brightyellow69rtse]

i just went out and measured from the water pump pulley to the radiator. i have exactly 4 inches of clearance. so leaving a 1" air gap it leaves me three inches to play with.  im guessing thats gonna be pretty hard to find a clutch and fan to fit that combo.

[Dino]

that's about the clearance I have on the dream 66 without a fan shroud...so far, no issues...looks like I got the same fan blade as well

Bryan

The flex fan I had was about the same distance from the rad as the clutch itself and my temps were fine, never had it overheat so this will likely work as well but it would be nice to have the shroud on, if only to protect myself and the car if the blade fails.

[Dino]

i just went out and measured from the water pump pulley to the radiator. i have exactly 4 inches of clearance. so leaving a 1" air gap it leaves me three inches to play with.  im guessing thats gonna be pretty hard to find a clutch and fan to fit that combo.

You'll be fine with these parts, I have a 3 row c-body radiator which is thicker than stock so I only have 3 3/4" between rad and pump.  The clutch is 2 5/8" thick and the fan does not make it thicker so you'll have 1 3/8" to spare.   

[Brightyellow69rtse]

awesome. I'm gonna look into a different fan though. i "occasionally" go over 4k rpm 

[Dino]

awesome. I'm gonna look into a different fan though. i "occasionally" go over 4k rpm 

I know moparsal has an original 7 blade steel fan for sale so you may want to contact him.

[ACUDANUT]

 Revving over 4K is fine in the fan dept. The water pump bearing however, is another story.

[A383Wing]

Dino...the fan blade will never see 4,000 RPM in it's life...the blade is on a clutch...yer engine will see 4K, but the clutch slippage will never allow the blade to see those speeds if my math is correct.

this of course being true unless the clutch itself locks up

Bryan

[A383Wing]

Revving over 4K is fine in the fan dept. The water pump bearing however, is another story.

AC pumps will see 4k all day long....if your engine is doing 2k to 3k, look at pulleys on crank & WP, the water pump is way smaller, so it will spin way faster than crankshaft...think of bicycle sprockets

Bryan

[Dino]

Dino...the fan blade will never see 4,000 RPM in it's life...the blade is on a clutch...yer engine will see 4K, but the clutch slippage will never allow the blade to see those speeds if my math is correct.

this of course being true unless the clutch itself locks up

Bryan

Ah yes, I didn't think of that.  Thanks!   

[Chryco Psycho]

What works well is the Jaguar clutch & A Flex-A-Lite 18 " 6 blade fan , the jag clutch is hsort enough to fit the b bodys prior to 71 which have about 1.5 " more clearance . The Jag XjS 6 or 12 cyl works

[Dino]

What works well is the Jaguar clutch & A Flex-A-Lite 18 " 6 blade fan , the jag clutch is hsort enough to fit the b bodys prior to 71 which have about 1.5 " more clearance . The Jag XjS 6 or 12 cyl works

I think that's what I got!   The blade is the flex-a-lite and I'm pretty sure this clutch is an oem replacement for Jags.

[Brightyellow69rtse]

im wondering how i can tell if i have an aluminum or stainless one? is there an easy way to tell?  id hate to replace it if the blades on mine are stainless.   also any fan can have a clutch on it correct?

[A383Wing]

What works well is the Jaguar clutch & A Flex-A-Lite 18 " 6 blade fan , the jag clutch is hsort enough to fit the b bodys prior to 71 which have about 1.5 " more clearance . The Jag XjS 6 or 12 cyl works

I think that's what I got!   The blade is the flex-a-lite and I'm pretty sure this clutch is an oem replacement for Jags.

me 3...but I got the non-thermal clutch

[Dino]

im wondering how i can tell if i have an aluminum or stainless one? is there an easy way to tell?  id hate to replace it if the blades on mine are stainless.   also any fan can have a clutch on it correct?

Should be plain steel, I doubt it's stainless.  Stick a magnet on it, if it falls off it's aluminum.  I would assume you can bolt most if not all fans to a clutch but I know some fans are labeled for use specifically with or without clutch.

[Brightyellow69rtse]

its very shiny and has been for prolly 13 years. so even if it wasnt magnetic it could still be stainless. ill have to investigate a little.