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Old Jan 16, 2024 | 06:22 PM
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Blower motor switch

Hello everyone, I have my dash apart repairing the Instrument panel. The blower motor is not turning on. Anyone know how to test the switch. All fuses are good. Thnx. 76 f100 no AC.
 
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Old Jan 16, 2024 | 06:52 PM
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Very often the problem is the heater resistor. check that before you go very fr.

The switch can be checked by putting 12v to the hot terminal and then reading the voltage on the output terminals.
 
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Old Jan 16, 2024 | 07:00 PM
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Awesome thnx.
 
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Old Jan 18, 2024 | 09:07 AM
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Is it not working even on high?
 
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Old Jan 18, 2024 | 06:27 PM
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Originally Posted by tbear853
Is it not working even on high?
haven’t had a chance to check it today. It didn’t turn on at all. This truck has been parked for 20 years. I’m not finding the relay, although there is a relay on the fender wall but the back of it doesn’t look like the replacement relays.
 
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Old Jan 18, 2024 | 06:41 PM
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Originally Posted by gweedo295
haven’t had a chance to check it today. It didn’t turn on at all. This truck has been parked for 20 years. I’m not finding the relay, although there is a relay on the fender wall but the back of it doesn’t look like the replacement relays.
Ford dropped the relay after '77. 78 & 79 models didn't use the relay.
 
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Old Jan 18, 2024 | 07:25 PM
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i am finding the PO converted many things on this truck..76 f100 has 460, 8 lugs wheels raised like a high boy, I need to figure out what everything is. probably a 3/4-1 ton. struggling to find a matching master cylinder. I replaced the heater core and blower motor.so I'll into the switched hopefully tomorrow. where would a resistor be? also anyone have any idea what size fuse I should install on the two hot leads from the voltage regulator to the alternator?

Thnx again...
 
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Old Jan 18, 2024 | 07:54 PM
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8 lug wheel by changing the steering knuckles from a 2wd F250 and the complete rear axle (9" to Dana 60) or (God forbid) did he use lug adapters? Master cylinder... is the issue all the ones you find have the brake lines coming out on the opposite side?

Did you test the blower before you put it all back together? Probably not, since you need a switch. I have heard talk about the reopo blower wiring being backwards. And if you color match connect and turn on the blower, it runs backwards.

None a/c truck, resistor is a drop in plate on front R/H side of the box. Blue, orange, red wires.


 
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Old Jan 19, 2024 | 07:29 AM
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Wow thank you very much. I did not test the blower motor prior to installing, yes all of the master cylinder lines are on the opposite side. Spent a lot of time looking for F100, then switched to 1-ton, this will be the 4th one, hopefully it arrives this morning. I'm thinking I may use adapters for the line fittings to work, only issue is the reservoir is a little smaller, not sure if that makes a difference though. I don't know why they use two different line size coming in when the actual brake line is the same size, I guess maybe to determine front and rear. still need to locate the relay, I'll try to post a pic of one I found on the fender well, just don't know what its for.
The front axle I think is a dana 9" the rear not sure but it's big, I' try and post pics of those as well.

Thanks again!!!!
 
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Old Jan 19, 2024 | 08:19 AM
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Rear diff.

Front diff.

Blower motor. Only wires going to it

Relay below regulator. Don’t know what it is for
 
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Old Jan 19, 2024 | 09:49 AM
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well i'm screwed again on the master cylinder, now one won't be in until Monday. the difference between the master I have in hand and the one on the truck is the line size and the reservoir size. i can adapt the line size to screw into the master but I'm not sure if the reservoir size makes much of a difference. any thoughts. Thnx
 
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Old Jan 19, 2024 | 10:07 AM
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Relay on the innerfenderwell I believe is just for the horn.

You can not have a FRONT axle that is a 9", because that is a common Ford truck REAR axle that is 1/2 ton 5 lug F100/F150.

If you have a 8 lug rear and I see a bolt on rear diff cover, so I bet Dana 60, which is a common 3/4 ton rear axle. Or you could have a Dana 61.

3/4 ton 8 lug front axle is the common Dana 44. Scrap off the grease dirt on the front pumpkin lower cast webbing (angles and look for a 44, 6CF 44, 44 6CF.

On the master cylinder normally the front or larger capacity reservoir is for the FRONT brakes.
 
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Old Jan 19, 2024 | 12:07 PM
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In cases where a blower resistor pack is bad, on high the resistor is bypassed anyway and the blower will usually still operate on high. If it won't blow at any speed, likely a switch, fuse, etc.

 
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Old Jan 19, 2024 | 04:29 PM
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Thank you everyone, I will try to address each answer. The front pumpkin has these numbers.
4 09 D7TA ZC. And below that number is 610010 4R.

Regarding the rear diff, there is a tag with a company name and half the numbers ground off, I called the company but they couldn’t help much without all the numbers. Is there a way to determine a Dana 60 or 61? Or does it really matter.

regarding the fan switch , I removed n put it back on. It works on high n low, not medium. I cannot
find a relay, or do you think it’s the switch?

regarding the master cylinder, the rear large reservoir feeds the front brakes. It also looks like he bypassed the proportioning valve So my question is, if the system is bled and is full, does it matter which reservoir feeds front or back. It doesn’t empty correct.
you say the front uses more, is that when the pads wear and more fluid is used to fill the space?
I think I’ll replace the fan switch anyhow. Sometimes works on low n sometimes not. If I wiggle it it works. Just gotta find the relay

I’ll attach some pics. Thnx
 
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Old Jan 19, 2024 | 04:42 PM
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