Heater core R&R

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Irishman999

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My wife just got a new camera so im confiscating the old one for the tool bag for another writeup.

So far All i've got done is the simple stuff done. Glove box is out, ashtray out and the ducting that comes off the front of the box. Will have pictures tomorrow.
 

nxtlevl

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Awesome....I love write-ups with pics. When I bought my truck, the guy gave me 3 totes full of misc. parts....In one of the totes was a brand new heater core still in the box.....:)
 

Irishman999

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Awesome....I love write-ups with pics. When I bought my truck, the guy gave me 3 totes full of misc. parts....In one of the totes was a brand new heater core still in the box.....:)

To get this heater core out its a real chore, but to be honest I've only spent a couple hours on it so far. Following things had to come out just to get to the damn thing- Glovebox, ash tray, inner fender well and a cable that controls your hot/cold valve. Also a couple vacuum lines.

I think so far its been more frustrating than anything done to the truck.
 

Old77

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Really? You had to take the inner fender well out to get to it??? That sounds odd. I may mark this off the list of things to do simply cuz I don't want to do that! I guess I should have thought about that when I had the whole front clip off during the build...
 

greencountry05

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I keep putting mine off on the S-10 because I'm no mechanic but I'm starting to think that it's not clogged but that the valve/servo/mechanism thingamajigger that tells it when to go from hot to cold is screwed up......aaaaaaaand I have no idea where that little bastard is. I would assume it's up under the dash somewhere but I don't exactly have time to go tearin' **** apart when I'm not even sure where it is lol.
 

Irishman999

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Really? You had to take the inner fender well out to get to it??? That sounds odd. I may mark this off the list of things to do simply cuz I don't want to do that! I guess I should have thought about that when I had the whole front clip off during the build...

Yea on the bottom of the housing There is a couple of studs coming out of the firewall that are completely blocked by the wheel well. The wheel well is not really that bad to take out, its got a ton of bolts but they are all easy to get too.

Green- Just jump in dude:roflbow: You can still drive it around with the dash all taken apart. Life sucks without a heater!
 

Old77

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Yeah, I know it's straight forward to remove that inner wheel well but sounds like an awful lot of trouble. I guess it's good that I don't drive mine in the winter very much:)
 

Mr Clean

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1/4" deep well, a couple of extensions and a swivel, and you can get the bottom two bolt with out taking out the inner fender.
 

Irishman999

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1/4" deep well, a couple of extensions and a swivel, and you can get the bottom two bolt with out taking out the inner fender.

Thanks for that. I really wish I had an air ratchet since its already out haha.
 

f6john

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I just replaced the heater core in my 85 C10 with air two weeks ago. I took the wheel well / inner fender out. Of the two nuts that have to come off the one on the right might be accessible but I don't see how anyone could get the nut off on the left bottom side with the inner fender installed. Maybe some of you "young guns" that are double jointed and have 20-20 vision in the dark could do it but not me. For me, getting the heater core housing assembly out of the truck was easier than accessing the core and getting it out of it's "home". I could not believe I would have to disassemble the housing to the degree necessary just to pull the core out and put the new one back in. Now that I have done it it would be a lot simpler for me on he next one (god forbid).
I already had the dash pad out for some instrument cluster work so that helped on the time frame but it still took me approximately 6 hours to do the job. I took some pics too but I haven't down loaded them yet. Need to do that to see if they are any good. I would hate to think what the labor charge would be at a shop.
 

Irishman999

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I just put it all back together today, I feel bad since I did not take pictures of the process for a writeup and add content to our site. The job was a huge pain in the ass. I put the fender back in and realized that one bottom bolt would be a real pain in the ass to get off, if you got it off there is now way in hell your going to get it restarted with wobbleys and extensions.
 

Irishman999

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I also forgot to mention the other half of the job was trying to get the blower motor working. Until today I have avoided learning how to use a voltmeter because they looked to complicated, Harborfrieght was out of test lights so got a meter for under 5 bucks.

After watching a youtube video explaining the device I look forward to electrical problems because it was so EASY. Went as followed,

Checked battery for volts and to verify my meter worked.

Checked the 2 posts on the fuse block for volts.

Removed plug off of the fan switch and verified it had 12 volts.

Next I switched over to OHms of resistance and checked the switch for continuity.

Next I went under the hood where the blower motor relay was mounted on the box on the passenger side.

The big main wire was good, so was the smaller signal wire. The purple wire out had nothing so I replaced the relay.

After that I had 12 volts at the purple wire going to my blower motor.

Still no go, I pulled out the fan assembly. 25 years of dirt, dust and other **** was pouring out of the vent hole. The shaft did not want to spin, 19 bucks for a replacement and finally have a heater in my truck.
 
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nxtlevl

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I also forgot to mention the other half of the job was trying to get the blower motor working. Until today I have avoided learning how to use a voltmeter because they looked to complicated, Harborfrieght was out of test lights so got a meter for under 5 bucks.

After watching a youtube video explaining the device I look forward to electrical problems because it was so EASY. Went as followed,

Checked battery for volts and to verify my meter worked.

Checked the 2 posts on the fuse block for volts.

Removed plug off of the fan switch and verified it had 12 volts.

Next I switched over to OHms of resistance and checked the switch for continuity.

Next I went under the hood where the blower motor relay was mounted on the box on the passenger side.

The big main wire was good, so was the smaller signal wire. The purple wire out had nothing so I replaced the relay.

After that I had 12 volts at the purple wire going to my blower motor.

Still no go, I pulled out the fan assembly. 25 years of dirt, dust and other **** was pouring out of the vent hole. The shaft did not want to spin, 19 bucks for a replacement and finally have a heater in my truck.

Awesome------------:favorites13: I need to go through my system and get things replaced someday....Doesn't seem like there's enough air blowing out..I think I read somewhere that there is a way to make these heaters blow harder, but I'm going to have to search for it again.....
 

Irishman999

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I would have to say its the most enjoyable fix on the truck yet. This fan I got from Orileys blows like a ****.
 

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