Blower motor!

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fireball517

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Well now that my damn truck has decided to have the blower motor go the hell out, and its on average this week 26 degrees, I don't know what the hell to do.

Checked the relay you can hear it click + voltage checks out, the motor I just pulled from a local pull a part and installed it worked good for about 10 minutes, hit a bump, then it slowed down and crapped out on me. Just like the last one.

What the literal f$&#, it can blow hot air year round except winter. Fed up with it at this point. What the hell am I missing?

EDIT: Will not work on any speed..
 
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89Suburban

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fireball517

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Thank you, I will check the other stuff later. I did run a jumper wire from positive terminal to the purple wire at motor and no go. Where exactly or how is exactly does the blower motor ground out?
 

cobra20

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there is a screw that is screwed into the case of the blower that has a ground wire running to the body
 

fireball517

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Does this look right?
 
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cobra20

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the bolt with the washer under it looks like it is your ground on your truck
 

fireball517

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Alright, I'm clueless anymore, will troubleshoot some more later.
 

350runner

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Simple test... with a volt meter set to check continuity out ohms. Connect the leads to the (1.) blower motor body (bare metal) and the (2.) Power power wire. If it reads resistance like .4 ohms the motor is still good if it doesn't read anything like when the leads aren't connected then the motor is bad.

Sent from the dust in front of you!
 

fireball517

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Is there supossed to be some resistor inline on the purple wire?
 

89Suburban

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Is there supossed to be some resistor inline on the purple wire?

No. If anything there may be a fusible link but that is not common. If you are jumping directly from batt POS to the purple wire post on the blower and it is not spinning then that motor is shot. The ground looks good to me that I can tell int eh picture. It is unusual to see a flat washer under the screw holding the ground wire though. Usually if anything there is a serrated washer that bites into the metal surface helping to establish a better ground.

Also a possibility that there may be something lodged in the fan blade itself. Take the fan assembly off, check for debris. Use jumper wires or cable to attach directly to the fan to test. Secure the flange of the fan motor to something with a pair of vise grips so it wont spin out of control.
 

kleedus

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I just went threw 3 used blower motors today before I got one to work right on my 85 c10.

I had to replace my water pump thermostat and blower motor to get my heater working right. and I still need to change the blower motor relay cause it only works on high.
 

fireball517

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The three you went through, did they just not work or gradually die on you?

I will test what others have suggested and get back soon with results. Maybe it's overvolting? Either way roughly 12.4V through relay.

Weird that it died after working fine. I did notice on my last one yesterday, that when I pushed the connector hard on the old motor, it spun very very slowly. It had come loose for some reason.
 
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89Suburban

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If it works on high only then the relay is doing its job. The problem is somewhere else like the fan speed switch or the resistor block or could be corroded contacts on the RB connection. Need to start testing things out with a test light and voltmeter.
 

Dadof2

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Misery loves company, glad to see I am not the only one dealing w/ this issue.
 

kleedus

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1 blower motor screeched but worked
2 thought it was a good one it worked fine before I parted out the truck it was in but it did not work when I installed it
3 blower motor worked when I hooked power to it to test it but when I installed it it did not work at all
 

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