Heater Problem

[Redneck86]

Ok so my heater will only blow out the vents now, wont change over to defrost. First thought was to check under the hood for any vacuum leaks that could effect it, didn find anything. Im thinkin i might have to look into the dash next, but yall have any help?

BTW, truck used to have AC, broke so i took it all off. How hard would it be to change out the face plates in the dash? Ive notice theres not as many options on the non AC ones.

 

[BroncoJoe19]

Mini-Tube Vacuum Hose

Mini-tube vacuum hoses are provided in the vacuum hose harness (19C827) assemblies. They provide greater flexibility with less tendency to collapse and are less susceptible to pinching. Service of damaged hoses is easily performed using standard 3mm (1/8 inch) ID vacuum hose and inserting the cut ends of the mini-tube into the standard 3mm (1/8 inch) vacuum hose.

1. Measure length of damaged area of the mini-tube vacuum hose.

2. Cut a piece of standard 3mm (1/8 inch) ID vacuum hose approximately 25mm (1 inch) longer than the damaged area of the mini-tube vacuum hose.

3. Cut off the mini-tube vacuum hose on each side of the damaged area.

4. Dip the mini-tube hose ends in Tetra Hydro Furan (THF) or Methyl Ethyl Ketone (MEK). This solvent will seal the mini-tube in the vacuum hose replacement.

5. Insert ends of mini-tube vacuum hose approximately 9mm (3/8 inch) into ends of the standard 3mm (1/8 inch) ID service vacuum hose section.

6. Shake the service joint to ensure solvent is dispersed and vacuum line is not plugged.

7. Test system for possible leaks in the serviced area.

Here is a vacuum diagram in acrobat format

If you can not open it, you must install the free reader from www.adobe.com

HeaterVacuum.pdf

 

[Redneck86]

I havent had any luck finding anything under the hood, that link wont work.

 

[BroncoJoe19]

I havent had any luck finding anything under the hood, that link wont work.

Redneck,

I just checked the link and it does work.

You need to install adobe acrobat reader on your computer so that you can read it.

Adobe acrobat reader is a free download which may be obtained at http://www.adobe.com

joe

 

[Redneck86]

Ive tried downloadin that on this computer before, it keeps f*ckin up. After i get my other computer workin it should work becuase i think it has Adobe on it already. But right now i still need to get this fixed and possibly swap out the face plates if its not too hard.

 

[BroncoJoe19]

Ive tried downloadin that on this computer before, it keeps f*ckin up. After i get my other computer workin it should work becuase i think it has Adobe on it already. But right now i still need to get this fixed and possibly swap out the face plates if its not too hard.

I would like to suggest that you ask a neighbor to download and print it out, or allow you to look at it on his/her computer, or go to the library. What is neat about it in a pdf file (adobe acrobat) is that you can enlarge it on screen to get a close up look.

Hmmm give me an hour, I'll see if I can post something else.

 

[BroncoJoe19]

I would like to suggest that you ask a neighbor to download and print it out, or allow you to look at it on his/her computer, or go to the library. What is neat about it in a pdf file (adobe acrobat) is that you can enlarge it on screen to get a close up look.Hmmm give me an hour, I'll see if I can post something else.

OK... I tried to print it to a file.

See if this works for you.

Nope... wasn't permitted to upload this type of file.

I'll try something else.

Here you go

Oh Boy... that's just about usless. The pdf file is MUCH better!



OK... the last try...



HeatVac1.bmp

 

[Broncobill78]

Ive tried downloadin that on this computer before, it keeps f*ckin up. After i get my other computer workin it should work becuase i think it has Adobe on it already. But right now i still need to get this fixed and possibly swap out the face plates if its not too hard.

This is an 86'truck right ? Have you ck'd the seals on all the blend doors and such ? Being 22yrs old it's not uncommon for the foam that's supposed to seal everything to become old & crumbly. It's not at all uncommon to have black chunks of foam floating around in the vents. The breakdown of filters and seals is a very common problem. I'd make *sure* that everything was intact and that you're not pulling in cold or ambient air when you're supposed to be moving clean, heated air. This can really ***** up the entire system, look it over.

 

[Redneck86]

No i havent but now that you mention that it sounds like it might be that. When i do swap it over to defrost it blows slightly out of the defrost vent and my regular vents.

 

[Broncobill78]

No i havent but now that you mention that it sounds like it might be that. When i do swap it over to defrost it blows slightly out of the defrost vent and my regular vents.

It's not always there but ck the insides of the ductwork for black crumbly dust. The seals were made of some type of blk foam, when it gets to be 20yrs old it crumbles, breaks down and all sorts of leaks pop up. The upside is that it's pretty easy to fix with any number of products. Last time I ran into it I actually used a chunk of one-sided sticky-foam that was intended as a sealant between a pickup bed and a cap. It worked great once I doubled it up for thickness and I had great heat with something like 5hrs work and I *didn't* have to yank half the dash and most of my ductwork. Obviously your mileage may vary but it's something to kick around.

Also, don't forget that most of the controls are vacuum based so if you have either cracked/leaking hoses the blend doors won't open/close completely AND (here's the kicker) if the engine isn't giving you good vacuum then none of those controls will work properly. If I had to lay $$$ on it I'd say it's probably a seal issue but best to be aware of ALL the things that could be throwing wrenches into the works.