Broken Model A Fan Blade with car damage

J

James G.

Senior Member
It surprises me to see how many club members are still running the original Model A 2 blade fans (not aluminum). One would think that after all the stories passed around these would be avoided at all cost.
I would like pictures of broken original Model A fan blades also showing the damage they did to the vehicles.
Does anyone know of personal injeries or deaths from a broken Model A fan blade?
PLease share and send pictures to jamessg1@verizon.net
Many thanks and be safe around those who insist on using these originals!
James Gregory
jamessg1@verizon.net
 
But, my original fan has been trouble free for 85 years. It must be good.:D

Actually I do have a small outward dent near the front of my hood, so I'm guessing a fan let go at one time.:mad:
 
Here are three photos of the damage to a water pump from the failure of an original two blade fan. As I recall that the only other damage was to the hood.

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Here's a few that I've seen, including the demise of a cheap 4-blade. More tales of woe can be found if you search the archives here.












Steve
 
Here's mine. Must have gone straight down, no damage to hood or radiator.
 

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There aren't any "good" Model A fans. They have a lot of things going against them - a high stress concentration at the front about 5/8" from center of hub, corrosion due to the double layer sheet metal construction, and other things. Eventually, enough fatigue cycles will occur to cause a crack at the previously mentioned location. Then, a few more cycles and the small crack grows suddenly causing failure. If your running one, keep a close watch for a crack. Maybe you'll catch it in time before it fails.
 
BN said:
There aren't any "good" Model A fans. They have a lot of things going against them - a high stress concentration at the front about 5/8" from center of hub, corrosion due to the double layer sheet metal construction, and other things. Eventually, enough fatigue cycles will occur to cause a crack at the previously mentioned location. Then, a few more cycles and the small crack grows suddenly causing failure. If your running one, keep a close watch for a crack. Maybe you'll catch it in time before it fails.
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I caught mine earlier this summer....

 
steve s said:
Here's a few that I've seen, including the demise of a cheap 4-blade. More tales of woe can be found if you search the archives here.



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Steve
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I have to think the tighter belt required by the alternator probably caused this pulley issue.
 
I bought an aluminum two blade fan just because of what I have read here. I have not installed it, yet. A recent thread on generators also talked about not having the fan belt too tight when you have a generator. I think I am okay, but I will check just to make sure.
 
Here is a fan blade that was a disaster waiting to happen. Note the welded spot next to the hub. I took this off of a friend/customers Phaeton last week It was replaced with a Two Blade Cast Alumninum from Snyders.
 

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I pitched 4 original 2 blade fans with cracks developing in the scrap iron earlier this year. I have one on my wall that on first inspection may be OK to use, but will see what beadblasting old paint and rust reveal. I am overly cautious with stuff like this. Likely I will run an aluminum fan and put this up for later use if I get the Fine Points build bug again. Selling my rdstr pu before it was finished after agonizing over many of the small details ruined that ambition for a good long time. Rod
 
I installed a new maintenance free, leakless water pump and 2-blade aluminum fan fro Snyder's last week.

Then I installed a set of repop splash pans on my 28 Tudor. Drove it in the 4th of July parade yesterday, which the temperature was 88 degrees and it worked great. Driving to and from the parade, no vibration at all from the new fan.

The president of our Model A club installed a new engine with a new 2-blade aluminum fan and water pump on his Model A and chased a vibration for a year. Someone told him to change out his fan, he put the 4-blade back on and got rid of his severe vibration.

I put my old 4-blade fan in the sand blast cabinet, will spray some dye penetrate on it and check for cracks. It will be repainted and mounted on the wall in my shop.
 
Use of an alternator does NOT require extra tightening of the belt. If the belt is adjusted properly (gen. OR alt.), with the engine off you should just be able to rotate the fan a little by hand
 
tbirdtbird said:
Use of an alternator does NOT require extra tightening of the belt. If the belt is adjusted properly (gen. OR alt.), with the engine off you should just be able to rotate the fan a little by hand
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If the pulley is the same as the generator and you were pulling the same amperage that would be true, but most alternators have a small diameter pulley, which gives them much less gripping surface, so they need to be tighter, plus most people need them for more amps to run high draw bulbs.
 
tbirdtbird said:
Use of an alternator does NOT require extra tightening of the belt. If the belt is adjusted properly (gen. OR alt.), with the engine off you should just be able to rotate the fan a little by hand
Click to expand...

I suggest you read the shop manual for a car with a V belt and an alternator.

You will find that the belt needs to be VERY tight. You will also notice the belt is wrapped around the pulley. As a general rule the alt pulley should not be turnable by finger.

As for the fan blades.
They all give warnings that they are going bad, you just have to know what to look for on the blades.

Many fans just should be thrown away. If it has pitting it is suspect to start with. Then you need to look at alignment and if there is swelling in the blades. I was shown one that came apart. It was from a professionally restored car by a large shop. The fan was bondo over heavy pitting.
Any fan needs to be taken down to bare steel and lightly painted such that any cracks can be found with regular visual inspection. NOTE I say any fan from the new aluminum to the old originals.

Never trust them always inspect them no matter how new or old.
 
Kevin and Tom, then why doesn't my belt slip on my alternator? Too tight a belt will destroy pump and alt. or gen bearings in a hurry. There are a lot of myths out there. And I run halogen bulbs, too.

I have a Ken Davis alt. and set it up the way he told me to. (convenient that he lives around the corner from me, I must say)
 
Jim,

NOW BACK TO THE SUBJECT AT HAND..."BROKEN MODEL A/A FAN BLADES"...
That would be a great idea...The day is going to come when not only a hood or radiator is going to get it, but human...man or woman.
This is the one and only item I wish the MARC/MAFCA Judging Standards Committe Chairpersons would totaly eliminate from their Blue Ribbon judging. They will when the first "human" incident happens wheather at a meet of not but not untill!
Thanks.
Pluck
 
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