Balancing the Fan

[29er]

I've never seen a discussion about whether the fan should be balanced before it is installed in the car. I have a repro 2-blade aluminum fan, but the question is relevant to them all. It would seem that the fan, like all other spinning things (wheels, lawn mower blades, etc) should be balanced so that undo stress is not placed on the water pump. There's even a thread by Tom W over at that other Ford forum that discusses how to balance the distributor rotor. So some questions about this issue arise:

(1) Can we assume the blade is in balance as it comes from the manufacturer?
(2) How would one test the balance of a fan blade?
(3) If, after testing it is found to be out of balance, how would one go about getting it into balance?

My Dad used to have a saying about trivial things: "It ain't a piano ." So, is concern over a balanced fan blade a "piano", or ain't it??

Mike

[bambooboy]

No expert here,but if real concerned I would start with a lawn mower pyramid cone for testing blade balance then move on from there if shows out of balance. Tom

[Mitch]

The reports on the two blade aluminum fan is that they are pretty good out of the box.
I have been popping them right on

[DaWizard]

I would not assume anything when it comes to balance on a fan blade.

If you have ever owned one of those hand held knife sharpeners with all the rotating disks in it, I would use something similar but instead of using steel disks, I would place a pair of bearings per side and set the blade on a shaft and rest it on 4 of those bearings. Hmmm, something tells me I should make something for a visual aid.

To balance the blade you can do one of 2 ways I think, by adding material, or removing material. Obviously removing would be easiest, and I wouls use something like a dremel so as not to remove too much at a time.

[Tom Wesenberg]

Here is a homemade fan balancer I built several years ago. Back then many of the aluminum fans had blades out of balance, out of plane, and out of pitch. Some even had a droop to one blade, as though it was removed from the mold while it was still too hot. All the fans I've checked for the past 5 years or so have been excellent and well balanced.

The bottom fan is the repro aluminum fan and the arrow points to where I would drill pockets to add lead for balancing. It's nice that they have improved, and this isn't needed any more.

[29er]

Thanks fellers. This one's a keeper! You all deserve the title, "ROAD SCHOLAR".

[Mitch]

[QUOTE=Tom Wesenberg;n3684]Here is a homemade fan balancer I built several years ago. Back then many of the aluminum fans had blades out of balance, out of plane, and out of pitch. Some even had a droop to one blade, as though it was removed from the mold while it was still too hot. All the fans I've checked for the past 5 years or so have been excellent and well balanced.

The bottom fan is the repro aluminum fan and the arrow points to where I would drill pockets to add lead for balancing. It's nice that they have improved, and this isn't needed any more.[/QUOTE)

As i mentioned that's pretty much my experience also..
Thanks for the confirmation