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Discussion Starter #1
My stocker finally went out this spring, I jumped the gun and bought a oreilys fan motor. After my car slowly creeps in temperature I notice that the fan sounds the same speed on high vs low. Sure enough, the oreilys fan motor says "single speed" in the description.

Where can I buy one a TRUE factory replacement so I don't run into this again?

Thank you.
 

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Discussion Starter #2
I know several of you have replaced fan motors. Where did you get them?
 

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I can't begin to tell you the time I've spent trying to find a correct replacement from all the parts houses, they all have single speed now. Ended up at junk yard. Freaking pain in the ass!! When you check at the parts houses, if the fan crosses to the V6 it's the wrong fan.
 

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Discussion Starter #5
Thank you for the confirmation of the single speed fan that sure is ridiculous that they can't produce a two speed.

Has anyone tried to open up the factory motor and replace the bearings?
 

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add a resistor in parallel, to another pin,. and you have your second speed.
 

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Discussion Starter #7
Yea but wouldn't that cause the fan to run slower not faster indy?
 

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yes

they give you high speed, you will only be missing low.
 

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Discussion Starter #9
The fan I purchased has a much lower rpm than my original fan and is why I am seeing temperature creep.
 

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exact same blade?

what is the rpm difference?

is there an airflow difference?
 

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Discussion Starter #11
I didn't do a back to back comparison because the bearings locked up on my old one but I am positive there is an rpm difference and therefore an airflow difference. Yes same blade
 

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rpm difference does NOT mean airflow difference,,,,,,,,

blade shape plays a role

and without measuring it, you are guessing.
 

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Discussion Starter #13
Rpm difference means airflow difference when you are using the exact same blade and shroud setup. I took the old motor out and put the new motor in the same factory setup.

If that was not a common variable I would agree with where you are going with this.
 

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get a better motor?

or use a markVIII
 

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The radiator electric motor was designed by Siemens, the stk Ford part number was F4ZH-8K621-AB. Check with Siemens and see if they have other electric motors that may work for you.
 

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Discussion Starter #16
^ Good info guys. I'll see what I can dig up and report back
 

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I posted a while back about these replacement fans/motors. Both Four Seasons and Pioneer are single speed.
Your solution is a VDO fan motor from Oreillys.
VDO PM9007 - Radiator Fan Motor | O'Reilly Auto Parts

The ad says it's single speed but mine is dual speed. I tested it with the KOEO procedure.
 

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Here's what I found out. The VDO is a single speed motor. But....
there are high and low speed connectors on the motor. The low speed connector has a resistor hooked to it and hidden inside of fan motor case. When the slow speed relay is energized in the CCRM; 12 volts are applied to the low speed prong on fan motor. That 12v goes through the internal resistor thus slowing the fan speed.
High speed gets a full 12v with no resistor and runs at a higher speed.

To test your motor for both speeds; first hook a ground wire to the ground terminal on fan motor. Ground it to the battery or an engine bay bolt. Now connect a wire to the + post of battery and touch the other end to either the low or high speed terminal on fan motor. Now touch the positive wire to the other speed terminal. Did you notice a speed difference? Do not touch the + wire from battery to the fan motor casing or the ground terminal on motor.
 

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resistor in parallel???? think I mentioned that
 

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resistor in parallel???? think I mentioned that
You most likely did mention it Indy.

I'm not sure that I would classify it as in parallel. One lead of a single resistor is connected to the low speed terminal and the other lead goes to the motor. Both speeds then use the same winding. This is an assumption based on my research.
 
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