Duct hose (repro) & fittings question
 

I bought repro heater & A/C duct hoses from Classic. The quality seems good but I'm having trouble fitting them over the plastic heater fittings. Seems too small/tight to fit over the hard plastic. Is there a tip or advice anyone can offer?
Thanks!

Re: Duct hose (repro) & fittings question
 

i am having this trouble as well. subscribed.

Re: Duct hose (repro) & fittings question
 

I recently had a similar problem, just an older year(66). Bought 2 tail-pipe adapters from Advance A/P--cut them to slightly shorter length, installed, and they have worked problem-free.
HTH,
sam

Re: Duct hose (repro) & fittings question
 

Use Duct tape like they they did from factory.

Every truck I have parted were installed this way..... :lol::uhmk::lol:

Re: Duct hose (repro) & fittings question
 

My heater ducts were from Brothers. They were very tight. It took me an hour or more to install the two dash defrost ducts. I have no fears of them coming off. They work great. Just reach in your tool box and pull out a large tube of patience. You will need the whole tube.

Re: Duct hose (repro) & fittings question
 

Are they plastic? The ones I bought are. I haven't tried replacing mine yet. You might try heating them up with a heat gun.

Hey JOJABOY Semper Fi

Re: Duct hose (repro) & fittings question
 

I will need to do this to mine soon also. Hey, that is a nice looking truck. Like mine but a little shorter.

Re: Duct hose (repro) & fittings question
 

What I did was instead of buying the ones from classic or LMC I just bought a universal fit one that was 2 1/2 in diam. It was real thin plastic with a steel wire in it. I was able to push that on much easier then the OEM style and I didn't need to use duct tape. my 2cents.

Re: Duct hose (repro) & fittings question
 

For the round heater outlet ends and the 1 round defrost vent end turn them clockwise as you go to put it on as though you are threading a bolt into a nut the spiral wound wire will then thread itself on to the end of the vent or heater box as you do this, make sure not to stop until defrost hose spiral wound wire has worked its way past the tabs that stick up to keep defrost hose on because if you stop without getting it on past these tabs it will just blow off shortly after turning the air on. The oblong heater defrost vent can be done somewhat the same but requires greater paitence. I've always found it easiest to install the heater box end first then extend hose so it sticks through top of dash and then install the defroster vent onto hose by rotating the vent onto the hose sticking up through defrost vent dash opening.
Paul @ GMCPauls

Re: Duct hose (repro) & fittings question
 

Thanks for all the replies. The hoses I got are similar to cloth with the wire spiral (not plastic). I think the advice about 'a tube of patience' and 'threading them on like a nut' are what makes sense to me. I think that will help a lot to get the quality install I am looking for.
Thanks again, you guys are great.

Re: Duct hose (repro) & fittings question
 

JOJABOY hit the nail - patience (a tool box full). I've bought from classic parts and have done three trucks. Just take your time and you will be good.

Re: Duct hose (repro) & fittings question
 

I attached mine to the vents first (out of the dash). I used the push and screw method to get the hoses on the round and oval vent pipes. Then I fed them through the dash and hooked them onto the heater box lastly. Patience, Patience, Patience....don't get frustrated. You'll get it.

Re: Duct hose (repro) & fittings question
 

If you are using OEM style, and you don't have patience that some the others do, here is what I did.

I cut the ends of the hoses, in the direction of the length of the hose, making the cut about 2-3 inches in lenght into the hose. This requires a set of heavy duty dykes or wire cutters to cut through the wire.

I then placed the end of the hose over the cap of a rattle to slightly spread the hose and to hold it into place at the wider position. This is basically near the same diameter as the factory hose fittings this will need to fit over. I then taped the end of the hose with quality friction tape (got mine a ACE HDWR), making the appearance near identical to what it did before the cut. This also helps hold it into position and from being able to expand wider an slip off.

Cut and install only one hose at a time. Install it quickly after removing from the rattle can. If not installed immediately, the hose will retract from the friction tape going back to its original diameter.

I found this to provide a tight enough fitment, without the frustration of forcing the fit. In appearance, it does not look obvious anything was altered, unless you really look closely. If done two trucks like this, and both have worked fine.

Re: Duct hose (repro) & fittings question
 

Additionally I am really glad that this thread was posted. It's always good to hear of the other methods people use.

If I were to do this again, I would try GMC Pauls method first. This sounds really cool, with no modification req'd.I've never thought of installing this way.

But, IF you find the frustration level excalate, I will say the method I mentioned above in this string worked well for me.

Re: Duct hose (repro) & fittings question
 

Had the same prob. Put some lube on them and they slide right on.

Re: Duct hose (repro) & fittings question
 

This was one of the most aggravating things I ever did to my truck, and I've owned it long enough to have to do it twice. I found a heat gun helped more than anything. Just don't force them or they'll come apart. Duct tape- the good black kind, does help for the ones you can't see.

oh, mine originally had a beer can (with the ends cut out) inserted as a flange to hold one of the hoses on...

Re: Duct hose (repro) & fittings question
 

:lol: I have done this to about 42 trucks, and well a burb or 2 and a few Blazers.... :lol: I have the best luck pulling the ducts out of the dash, installing the duct tubing onto the ducts. This way they are wright where I need them to work on them. Like Paul says, you thread them on like a nut. Then I feed them down through the dash and install them onto the floor duct. I just wiggle them back and forth as I push them on. Sometimes it can be hard to get the left duct hose over the floor vent, but for that I push on the spring with a windshield gasket plastic tool.. WES

Re: Duct hose (repro) & fittings question
 

the LMC hoses simply do not fit correctly. I've never, ever wanted to put my head thru the windshield more than trying to install the defrost hoses on the vents. How could something so simple be so stupid.... Have heard Classic Parts fit better, unfortunately only after I bought the LMC crap. And only discovered they don't fit after waiting an extra week because the shipping was messed up. When will I ever learn.

Re: Duct hose (repro) & fittings question
 

Use vasoline i have used on other items seems too work

Re: Duct hose (repro) & fittings question
 

thanks best view

Re: Duct hose (repro) & fittings question
 

Vasoline if you want greasy goo everywhere and the tube not to stay in place. Maybe some wire or gasket lube as it will evaporate. But it's not needed.
They go on. You just got to get the hang of it. Best to place on a fitting not installed to stretch a bit and get the tube more workable.
They will also in a way screw on. The tabs on a fitting will follow in the wire coil like threads of a screw. If you are doing the defrost vents, place tubing on the vent and drop from the top. Then work other end of tubing onto the fitting under dash. They are not easy at first. Then you get the idea, and they actually go on reasonable easy.

Re: Duct hose (repro) & fittings question
 

I bought the replacement defrost vents, and it went together smoothly. Maybe the new repo vents are smaller? I know one of them is oval and the other is round. I figured the oval one was to make room for the radio, but it didn't seem to be in the way. I'm still perplexed on that deal.

Re: Duct hose (repro) & fittings question
 

yes there are oval, or rounded rectangle connections at the right defrost vent on the dash and where the right a/c vent duct connect to the air box. None of the hoses come with this shape. I had to snip the metal ring in a few instances to get the hoses on. Miserable miserable job. At least my seat is out so my old bones can at least get under the dash. Then I can't see of course without my glasses - getting old sucks, ha. What I'd give for a gifted helper that knows where to shine a light!

Re: Duct hose (repro) & fittings question
 

Lot of good advice in this thread. I used the plastic style duct kit and it was difficult and required patience, but a hair dryer to warm up the ducts helped a lot, and a drop of Astroglide from the drug store was an excellent lube and also helped a lot. It is a lube that will dry so not remain slick for life and cause the ducts to slip back off.