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| | | | Joined: Apr 2009 Posts: 554 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 554 | I purchased a replacement 12v motor for my economy or recirculation heater. It appears I got one designed for the fresh air heater. It will fit my heater core fine but it has a 5/16 shaft instead of the 1/4. I am hesitant to drill out the fan hole since this would leave a very thin area supporting the fan on the shaft. Has anyone done this? Anyone know if this motor would have the correct speed for the fan?
That leads to the second part of the question- the fan looks like a small version of the 4 blade engine cooling fan. It will mount on the shaft facing either direction. Reversing the polarity of the motor reverses fan direction so there are 4 possibilities for the fan. How can I determine the correct orientation? I know which way I ultimately want the air flowing but just testing the fan on the motor there is so much air blowing around I am having a mental breakdown figuring out the most efficient orientation.
Chuck | | | | | Joined: Aug 2000 Posts: 800 Shop Shark | | Shop Shark Joined: Aug 2000 Posts: 800 | Just look at the fan blades. They will indicate if they are pushing or pulling air.
You may want to have the shaft of the motor turned down to your requirement and then you'll be on your merry way. Check around for a machinist shop or maybe a retired machinist in your neighborhood. They'll set you straight. | | | | | Joined: Jan 2009 Posts: 1,644 Shop Shark | | Shop Shark Joined: Jan 2009 Posts: 1,644 | Also classic Parts of America has a 12 volt fan motor that has a 1/4 inch shaft I just did Mine and it works real well I just had to drill out the mounting holes alittle .Part #68-009 at $39.95 .
Pete
Last edited by Pete52; 10/30/2009 8:32 PM.
| | | | | Joined: Apr 2009 Posts: 554 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 554 | Thanks for the responses. I think a different motor with the right sized shaft is my best bet unless someone that has actually sucessfully drilled out the fan speaks up.
Pete, do you remember if the part of the fan with the set screw faces toward or away from the motor? Since it will push or pull either way by reversing the polarity I cannot tell which way it works best. The 6v motor is spinning too fast to tell since I am checking it with 12v.
Chuck | | | | | Joined: Jan 2009 Posts: 1,644 Shop Shark | | Shop Shark Joined: Jan 2009 Posts: 1,644 | The set screw is in front if You are looking down at the motor or closer to the end of the shaft.
Pete | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | You want the fan blades very close to the core. If you put it in the other way it will draw most of the air from around the area, not from the core. | | |
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