Author Topic: No Heat, No A/C  (Read 4005 times)

Offline theaddictedchef

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No Heat, No A/C
« on: January 13, 2013, 11:45:34 PM »
I'm a newbie as you can see.....

I have a '73 K10 and the heater was dc'd from the motor in the engine compartment.  Also, heater hoses bypassed the heater core (did I explain that correctly?) and go directly from the block to the radiator. 

I connected the wires to the blower just to see if the fan would come on and nothing.  I think I am starting from scratch.  I read the post on replacing the blower motor with a '94 and I was in Autozone today and it is $16 for a new blower. 

So my question is - where should I start?  I'm new at this mechanical stuff and I don't even have the right terminology down so I might just post pictures until I figure out what I am talking about. 

Thanks guys - the info so far has been great.
The Journey IS the Reward......

Offline bake74

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Re: No Heat, No A/C
« Reply #1 on: January 14, 2013, 06:12:05 PM »
     Replacing the blower motor will take care of the blower motor issue.  But, it depends on if the heater actually works anymore.  This might be why the p.o. Bypassed the whole system. ( it seems that he might have bypassed the heater system because the core possible got plugged ).
     If the heater core went out then that requires a more in depth repair.
     Did you hook your blower motor straight to 12 volts to see if it worked, or did you use the trucks electrical system ?
     I would make sure the blower motor is bad first, then replace and see if rest of system is working.  Maybe you get lucky and that is all that is wrong.
     If you need more help we are here to help you out.
« Last Edit: January 14, 2013, 06:13:59 PM by bake74 »
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline Jason S

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Re: No Heat, No A/C
« Reply #2 on: January 14, 2013, 10:00:55 PM »
My first thought is that the heater core was bypassed because it was leaking.

I presume that the truck has factory air conditioning?  As Bake74 said, check the blower by connecting straight to 12V to see if the blower is even an issue. You can also pull the power wire from the blower motor and use a volt meter to see if you have current at the power wire. 
1973 GMC K2500, Super Custom, Camper Special, 350, TH350, NP203, 4.10's
1974 Chevrolet K10, Custom Deluxe, 350, SM465, NP203, 3.73's

"1) Peace through strength; 2) Trust but verify; 3) Beware of evil in the modern world"

Offline theaddictedchef

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Re: No Heat, No A/C
« Reply #3 on: January 17, 2013, 01:13:13 AM »
I plugged the dc'd wire to the blower motor and nada.  So I think what you're saying is to go directly to a power source?  I will do that Friday morning. 

I have looked on here and it seems that my truck will take a '94 blower motor with better air output.

Yes, my truck came with factory air.  It is not hooked up and all of the hoses are gone, but that is something I can work on over the next 2-3 months.  It won't be blazing hot here until the first of May.  This past weekend we got to 26 degrees which is the lowest I've seen in several seasons.  I was born and raised here and I like to describe it as two seasons - hot and not that hot. 

Checked at Autozone and they have the heater core for $17 and the blower motor for $32.  Just in case the blower is shot I know that I can get one.  I want to make sure about all of this as there is no reason not to replace it all once I get in there.  Am I thinking about the right way? 

In addition, I replaced my cigarette lighter (my phone keeps dying and I need to charge it) and no power to that at all.  I have checked the fuse panel and nothing is blown.  Any thoughts?

Thanks for the info, this forum is exactly the kind of thing I needed. 
The Journey IS the Reward......

Offline theaddictedchef

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Re: No Heat, No A/C
« Reply #4 on: January 17, 2013, 01:13:46 AM »
Here's a picture of the newest addition.........
The Journey IS the Reward......

Offline bake74

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Re: No Heat, No A/C
« Reply #5 on: January 17, 2013, 06:48:35 AM »
     Yes, we are saying to hook the blower motor directly to your battery to see if it works, you only have to touch the wires to see if it turns momentarily.
      How good are you with electrical ?  I would start at the cigarette lighter and check power, then work your way back through the electrical.  You can find complete wiring diagrams in the technical  section, open it up and in the search window type " wiring diagrams ", it will pull it up.
     I have just scanned in some PDF forms on the heater and a/c system for another thread,  http://forum.73-87chevytrucks.com/smforum/index.php/topic,25319.0.html , if you need something else I can look it up and scan it in, good luck.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline theaddictedchef

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Re: No Heat, No A/C
« Reply #6 on: January 18, 2013, 01:09:28 PM »
Can't thank you enough. 

The Journey IS the Reward......

Offline frotosride

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Re: No Heat, No A/C
« Reply #7 on: January 18, 2013, 08:12:29 PM »
With the exception of money there's no reason not to do both the core and the blower at the same time. You have to pull the blower when you take the air handeler off to get to the core anyway.
Oh and by the way I like the truck. I like the way the factory paint looks too. I can't wait to lift mine..come on tax return...this is an ask for forgiveness situation so the wife will find out about it when the lift is delivered unless im here to intercept.
"Beat it like a red-headed ford"
1987 v10 Silverado(LQ4), 87 R10,83 K20, 83 cucv 6.2 Detroit
2006 Boulevard M109R 109 cid,2019 M109R BOSS
2009 Jeep XK, (future LS Swap)
GSXR 750 engine awaiting go kart