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Heater Wiring Harness for HD Heater No AC

73k5blazer

End the H1B Program!
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I'm looking for the the switch to resistor/blower wiring harness for 81-87 Full size with Heavy duty heater and without AC. You can tell if you have HD heat if you have a four prong resistor on the heater box. The harness is very simple runs from the blower switch in the dash, along above the heater box, through the fire wall into the engine compartment and to the resistor. Has four prong plug to the reistor, and 1 lead come from the resistor to the actual blower motor. I'll take the switch to if you have it too. THis harness differs from trucks without HD heat and W/AC, I'm looking for the 1 for trucks only with HD heat and without AC. I'm adding HD heat to my 1973, and also putting in the 80's style ventialtion system (no contanst on blower), so that limits the years to '81-87 and 88-91 sub/blazer (but those years are pretty rare in blazer/sub to find without air)
I'm not a cheapskate, I'll pay a fair price.
Thanks!
 
Are you trying to tell us it gets COLD in Michigan? Who'da thought? Would a CUCV have it? I've got a carcass that should still have that part, if it's the right one.
Jimbo
 
I dunno if the CUCV's had them but you can tell, if it has the 4 prong resistor, then it's HD heat. The resistor is mounted right next to the blower motor in the engine compartment.
Yes, it's cold, but I am warm. I want it for my K5 frame-off which is still about 9months away from completion, I put the HD heat in it (It had AC from factory)(K5's need the HD Heat), I found the case NOS, but the harness is nowhere to be found. I'm in the middle of wiring it, that's why I could use it now. The wiring diagrams I have don't show anything different for HD heat, but there MUST be, it has 4 prongs on the resistor, the diagrams only show 3. I think I may just need a different year wiring diagram that shows it, then I could just do it myself. But the factory self-contained harness would be best.
 
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I am running heat in my truggy project since most of us wheel in the winter

. I took the whole underdash system , and firewall parts off a 83 k5 with heat only ( ohio truck ) .

The whole heater harness plugged right into the 73-75 pickup harness I am using .

They exist , but back home I bet you guys crushed em all already :(
 
The yards are getting scarce for our trucks. Most yards don't have any left. Then ones that do, have like 1 mabey 2. Slim pikkins. I might try saginaw, somebody said their yards have alot more of these trucks.
The 70's and 80's trucks differ in their heat system. Not to say they won't work together, but the underdash box is different in the 70's, has a huge opening on the passenger side on top pointing up, underneath the dash (I always wondered why my '73's dash would get really hot!), to accomodate the "passthrough" ventilation system. The switch was wired with a constant on blower, it wouldn't shut off. In the 80's they did away with the pass-through vent. system. That's why I want an 80's HD heat harness. They are wired a bit different and have a off position on the switch.
 
I might have one, will have to look. My first k5 (86 custom) only had heat and I removed all the wiring and stuff when it went to the scrap yard. I'll post up in a few with what I find.
 
Most appreciated! Most K5's had AC. But most of the ones w/o AC, had HD heat.
 
My visual appraisal of the CUCV is that it is the HD resistor and harness. Mine is complete, switch to resistor, so let me know exactly which pieces you want.
Jimbo
 
Oh.....yeah.....jackpot!
The CUCV's don't have A/C right?
Blower switch, and the harness. I have brand new HD resistor and HD motor, HD case, box, core and everything else related. So just the blower switch and the wiring from switch to resistor and I think 1 lead shoots off from the resistor and plugs to the blower motor. Shoot me a PM with your $$, plus ride to zip 48438. Thanks!!!!!!!!!! Your a savior!
 

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