Heater refurb question

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Selo

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I am refurbishing a 1984 I6 three on the tree. The truck has the standard heater and does not have AC. The heater unit was full of mouse nest and riding in the truck without the fan on was unpleasant due to smell. Also control levers don't work well. The core needs replacing and fan wheel has broken blades (fan available at LMC).

Looking on LMC, the choice for the motor mentions a vent hole. The oem motor, which I might keep since so easy to access if it fails, does not have a vent hole. Choices on RockAuto don't mention a vent hole. Is there something I need to know here about motors?

I plan to replace the resistor. I may replace the control module. The cables aren't available for the standard heater no/AC so the control cables I will try to lubricate. I am going to clean the module and grease with silicone grease. I will be taking the interior air control box apart when I install the core to clean it up. The housing where the motor mounts in the engine bay needs a good cleaning. Finding I have to remove the freakin inner fender well to get to ONE freakin bolt on the motor housing!

I'm also going to remove the manual floor vents to make sure they aren't full of rat **** stuff as well.

Experienced advice appreciated!

Selo
 

yevgenievich

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It is possible to get to that one bolt with 3-4 extensions and a couple of swivels.
 

donnieray

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It is possible to get to that one bolt with 3-4 extensions and a couple of swivels.
What he said. 1/4" extensions, swivel and deep well socket.
 

Dmack

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I would try to find a used system. I pulled the complete inner and outer heater box assemblies out of a 73 donor truck. Complete with controls. Pretty simple. My83 had a gutted ac system. Bolts straight in.
 

Selo

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What he said. 1/4" extensions, swivel and deep well socket.
Hey I'm with you both because I tried that. I can get a 1/4 in socket with swivel to the bolt, I just can't get my fingers in there to guide it onto the bolt head. Also the swivel allows the socket to drift down. Without my fingers in there can't get it on the bolt. I really don't see how I'd put it back in if I did get it out. Very appreciate the reply to help. Selo
 

Selo

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I would try to find a used system. I pulled the complete inner and outer heater box assemblies out of a 73 donor truck. Complete with controls. Pretty simple. My83 had a gutted ac system. Bolts straight in.
Not a bad idea, but I'm too far in now! I'll keep that suggestion in reserve however.

Thanks,

Selo
 

chengny

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Hey I'm with you both because I tried that. I can get a 1/4 in socket with swivel to the bolt, I just can't get my fingers in there to guide it onto the bolt head. Also the swivel allows the socket to drift down. Without my fingers in there can't get it on the bolt. I really don't see how I'd put it back in if I did get it out. Very appreciate the reply to help. Selo

Try releasing that lower RH screw from inside the plenum. Rather than fighting to get a socket on the hex head, it's way easier to access the threaded portion. There are two ways to reach it. Whichever way you decide to use, just grab it with a small pair of Vise-grips, Channelocks or even just pliers and crank it CW as if you were tightening it. It will back out towards the engine side.

You will probably run out of threaded section to crank on before the case can be pulled free. But by then there will be a good sized gap between the firewall and the blower case. At that point you can use a pair of needle nose pliers to reach down into that gap and finish backing it out.

With the blower/motor assembly removed, you can get to the threaded end of the bolt this way:

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Or, since you are cleaning out the mice stuff, you will most likely have the fresh air damper removed and you will even be able to see what you're doing. If you do it through the opening in the firewall you'll pretty much be flying blind:

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When it comes time to reinstall, put a piece of duct tape over the bolt head to prevent it from falling out. Then - again working through the gap - get the bolt started in the hole. When there are some threads exposed on the inside, bring the bolt home with your pliers.

It might take a couple of attempts when reinstalling, but you'll get it.
 

75gmck25

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I removed all the bolts on the inner fender and just dropped it down to reach that last bolt for the heater housing. In the grand scheme of things it wasn't that much more work. I had more trouble getting the housing back together, working around the firewall insulation that kept getting in the way when I was trying to bolt it back in.

Bruce
 

highdesertrange

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tip for universal extensions that flop around. take black electrical tape and tape the wobble part. don't tape it so much that you can't move it but enough to make stiff. surgical tubing also works but everyone has the black tape on hand. highdesertranger
 

Selo

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chengny,

Great idea. and yes I do have the air handler out etc and can get to the screw threads inside the cab. Putting it back using the tape idea great as well. Thank you

Bruce,

wouldn't you know I have ONE fender well bolt down below the fan housing that is spinning. I've go to decide how I;m going to deal with that. Otherwise your idea would work no doubt. Thank you.

highdesertranger,

I may just give that a try. Thank you,

I'll let everyone know how I make out.

Selo
 

Selo

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To my advisers!

Cables for my non-AC heater do not seem to be available as repros, have any of you fellows ever lubricated heater control cables?

I'm planning to use silicone grease on the Temp Control Assembly after if clean it up.

Selo
 

chengny

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To my advisers!

Cables for my non-AC heater do not seem to be available as repros, have any of you fellows ever lubricated heater control cables?

I'm planning to use silicone grease on the Temp Control Assembly after if clean it up.

Selo


What's wrong with your current cables? Since they are not exposed to the elements, it's rare to see either a temperature or mode control cable that is rusty. If they are hard to move, I would be looking for kinks/improper routing in the cables themselves. That, or maybe a problem within the control panel. It might even be a sticky temperature/mode damper. Maybe disconnect the cables from the damper actuating arms and test them for ease of operation.

If things seem to improve with the dampers disconnected, operate the dampers manually. They should flop back and forth freely.

If you still have difficulty stroking the cables - with the damper ends disconnected - you probably have an issue in the control panel.

I think that silicone grease was what the factory used to lubricate the control panel.

Here is a hint for when/if you pull the cables from the actuating arms:

and there are 2 of those spring steel stamped washer things that you push on and they hold but are a bitch to remove. Most of the time the studs break on me


Early on (after snapping off a few posts - and losing dozens of the Jesus clips), I figured there must be a better method of removing them than just trying to pry them off.

There is (a better method). Screw them off - like they were little round nuts.

Insert the tip of a small screwdriver under one side of the Jesus clip (and create a light force in the upward direction). That tilts the clip. While maintaining that pressure and tilt, rotate the clip. Generally you can use your fingertips.

The sharp inner edges of the clip will start to cut tiny threads on the post as it rotates and it will begin to climb. Usually you only have to get it started and then you can remove the screwdriver. Keep turning the clip and it will thread right off.

My wife says I need to get a job.
 
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Selo

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chengny,

I will definitely remove cables from control module to test. You are correct in thinking I was making the assumption the cables did not "slide" well because if I tried to make them move by pushing or pulling the end while still connected to the module, they don't move well. So I will check it out. Thank you also for the tutorial on the clips.

Will be working in garage later today so hope to report back late or in the AM.

Selo
 

75gmck25

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My truck had spent a lot of time on the farm and when I first opened the heater box to clean it out I found a real variety of things. The biggest glob was the nest the mice had made from the firewall insulation, and then there were nuts, bolts, a pen, seveal 30-06 rifle cartridges, and a match book from a local bar. Once I got it all out of the way, then blend door worked a lot better.

Bruce
 

Selo

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chengny,

I took the cables off of the control module last night. Interesting that one cable showed no kinks or bends, but when I had it off the module could move the cable wire and feel an abnormal bend in the wire inside the cable cover. I straightened that as best I could and the cable works much smoother now. The other cable was OK. The module is good as well. I will still lubricant the cables as best I can, also the module with silicone grease.

Of course the deeper I get, the more issues I find. Taking the core out of the heater distribution assembly, found one of the "strap like" brackets was rusted through and in two pieces. I'm looking on Craigslist for heater parts. Wonder if those straps are the same in the AC equiped trucks as in my non-AC truck heater.

Whats with the vent hole in the replacement blower motors? My OEM does not have a vent hole. Once I'm sure which to order will be getting parts ordered. I need the motor AND the cage as my cage is missing a vane or two. Regardless will begin scrubbing rat pee and poo off housings and will get the fan motor housing off the truck today come hell or high water.

Thanks for your help.

Selo
 

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