CK5
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1978 K5 LS/NV4500

I remember a guy who had a newer Silverado had some 327 emblems made up.... but a 5.3 is techinically 325.... thought it was interesting at least.
 
Replaced the front pinion seal, so we’ll see if I put the right about of preload back on the nut cause I forgot to mark it before tearing it apart. Not like I use 4x4 a lot anyway. So that’s one less thing that leaks now.

Lifted the rear an inch because it always looked like it was saggy. Now I might need to take .5” out again lol. I don’t know.

Winter is coming. First time driving with the top all buttoned up on the windiest day of the year and it’s not bad at all. Nice to not smell like exhaust either. Wow those can be a b!t<# to snap together. The hardtop will always look better though.

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HVAC experts, help needed. Fan control has never worked. The fan switch seems real sticky and is probably bad. Going to order a new one. My question is, is there supposed to be power from this pig tail connector that plugs into fan switch?

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I have no power at any of these wires, but if I run power to one of them, the blower turns on high. Not really sure where to start if I’m supposed to have power here.

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I'm no expert, but I believe that there should be power to the switch on just one terminal. The switch sends it to the resistor pack in the top of the evaporator housing, and then it goes to the blower motor. It changes which terminals get power, and when high speed is selected, then the resistor pack is bypassed and the high speed relay is energized.
I think, but I am not positive that the high speed relay sends power through to the motor all of the time, just depends on if it is using the normally closed contact, or the normally open side.

I don't know which terminal at the switch is supposed to be power, though. Maybe you can find a blown fuse, or a dirty terminal on a fuse?
Also look for a plug between the blower switch plug and the main harness. I believe that they had a different sub- harness for heat, or heat and A/C. So the sub harness would plug in for whichever system the truck got.

I can't remember many exact details on that vintage, so don't be surprised if I am wrong.
 
Replaced relay. Didn’t help. Found brown wire unplugged and I plugged it back in. Fan turned on but I have no control over the fan speed and I can’t turn it off. Resistor bad? Someone obviously unplugged it before I had it cause something went bad.
 
Replaced relay. Didn’t help. Found brown wire unplugged and I plugged it back in. Fan turned on but I have no control over the fan speed and I can’t turn it off. Resistor bad? Someone obviously unplugged it before I had it cause something went bad.
I’ve never had air on any of my old squares but I know the fan always runs on low with the key on. I usually unplug the wire at the fan motor under the hood in the summer time.

Not much help except that the fan running I think is normal.
 
I’ve never had air on any of my old squares but I know the fan always runs on low with the key on. I usually unplug the wire at the fan motor under the hood in the summer time.

Not much help except that the fan running I think is normal.

I was just reading this online. Apparently in the earlier models the fans just ran on low all the time to, keep air moving, keep condensation out of vents, filter out carbon dioxide, etc. Many different theories. So I’m guessing my blower switch is still bad.
 
I believe it should shut off the blower when you switch the control to off instead of heat or a/c.
Page 16 Air Conditioning RPO C-60
 

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There should be 12v to one of the blower switch terminals. If everything else is working you can test the switch by using a jumper from the 12v terminal to the others and you should here the fan run on low, medium, and high depending on the terminal.
The blower resistors fail often enough it's worth testing continuity with a meter.
 
There should be 12v to one of the blower switch terminals. If everything else is working you can test the switch by using a jumper from the 12v terminal to the others and you should here the fan run on low, medium, and high depending on the terminal.
The blower resistors fail often enough it's worth testing continuity with a meter.

I can’t figure out why I don’t have 12v to one of the terminals. Power going to relay. New relay. Blower runs with switch unplugged.
 

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