The Ford Barn - View Single Post - Fan Tapered Hub Damage

Benson · 11-15-2024, 10:37 AM

See attachment of instructions to install fan from the manufacturer.

This MAY explain some other reasons why your fan was damaged.

You most likely will need to replace damaged fan and make the checks listed in sheet while installing new fan.

I would buy fan from a trusted parts house. Many times the fans you buy from ebay or the trunk of some one's car are defective and seller trying to get rid of them.

Some parts have only one source, others have more than one source, some good , some not so good.

The Ebay seller may not even know that the parts he has are defective.

As an example: Berts Model A Center knows which parts are good and sells the known good parts.

Berts uses these parts daily in their repair shop and in rebuilding original Engines and building The New Burtz Blocks and they know which ones are good.

www.Modelastore.com

Below is installation instruction sheet from manufacture of the fans.

A-8600-A TWO BLADE CAST ALUMINUM FAN
MOUNTING INSTRUCTIONS

It is very important that you test fit and rotate your fan before installing it with the castle nut. Slide the fan into position on your water pump and rotate the fan by hand to see if the ID of the fan hub is rubbing anywhere. On a new fan, this will be obvious by the scuffing of the paint. If you feel any drag or rubbing, you will need to file or sand the snout of the water pump wherever the high spot is. High spots are caused by irregularities in the casting, castings being bored off center, or castings that are slightly larger in diameter than normal.

Why do you have this problem with a new aluminum fan but not an old steel fan? A casting requires more material thickness than a stamping in the hub area. If these fans were made with the bore as large as a stamped fan, there would be little to no material left to support the edges of the belt pulley. The result would be the edges of the belt pulley braking off very easily.

Install the key in your water pump shaft and slide the fan into position. You should feel the fan bottom out on the taper of the shaft. If this does not happen, your fan shaft may not have been cut deep enough for the key to set in the proper position. If you have this problem, first check to be sure the key is seated all the way into the groove of the shaft. If it is in all the way and you still experience this problem, file the top of the key down slightly so there is no interference when the fan is slid into position.

If the water pump is off of your car, put the fan in position, hold the pump in a vertical position and lightly drop the pump on the impeller end to seat the fan tightly on the taper. It is best to drop it on a firm surface such as an anvil or a concrete floor. Now you can tighten the castle nut and insert the cotter pin.

Note: The depth of the taper does vary on shafts. If you find that you can not get the nut to go down far enough to get the cotter pin in place, dress the back of your castle nut down with a file or belt sander until the proper depth can be achieved.

11-15-2024, 10:37 AM	#4
Benson Senior Member Join Date: May 2010 Location: Central Highlands, Cen~Col Posts: 2,896	Re: Fan Tapered Hub Damage - help with cause and repair See attachment of instructions to install fan from the manufacturer. This MAY explain some other reasons why your fan was damaged. You most likely will need to replace damaged fan and make the checks listed in sheet while installing new fan. I would buy fan from a trusted parts house. Many times the fans you buy from ebay or the trunk of some one's car are defective and seller trying to get rid of them. Some parts have only one source, others have more than one source, some good , some not so good. The Ebay seller may not even know that the parts he has are defective. As an example: Berts Model A Center knows which parts are good and sells the known good parts. Berts uses these parts daily in their repair shop and in rebuilding original Engines and building The New Burtz Blocks and they know which ones are good. www.Modelastore.com Below is installation instruction sheet from manufacture of the fans. A-8600-A TWO BLADE CAST ALUMINUM FAN MOUNTING INSTRUCTIONS It is very important that you test fit and rotate your fan before installing it with the castle nut. Slide the fan into position on your water pump and rotate the fan by hand to see if the ID of the fan hub is rubbing anywhere. On a new fan, this will be obvious by the scuffing of the paint. If you feel any drag or rubbing, you will need to file or sand the snout of the water pump wherever the high spot is. High spots are caused by irregularities in the casting, castings being bored off center, or castings that are slightly larger in diameter than normal. Why do you have this problem with a new aluminum fan but not an old steel fan? A casting requires more material thickness than a stamping in the hub area. If these fans were made with the bore as large as a stamped fan, there would be little to no material left to support the edges of the belt pulley. The result would be the edges of the belt pulley braking off very easily. Install the key in your water pump shaft and slide the fan into position. You should feel the fan bottom out on the taper of the shaft. If this does not happen, your fan shaft may not have been cut deep enough for the key to set in the proper position. If you have this problem, first check to be sure the key is seated all the way into the groove of the shaft. If it is in all the way and you still experience this problem, file the top of the key down slightly so there is no interference when the fan is slid into position. If the water pump is off of your car, put the fan in position, hold the pump in a vertical position and lightly drop the pump on the impeller end to seat the fan tightly on the taper. It is best to drop it on a firm surface such as an anvil or a concrete floor. Now you can tighten the castle nut and insert the cotter pin. Note: The depth of the taper does vary on shafts. If you find that you can not get the nut to go down far enough to get the cotter pin in place, dress the back of your castle nut down with a file or belt sander until the proper depth can be achieved. Last edited by Benson; 11-17-2024 at 02:18 PM.