# vacuum hose reduction



## carpdad (Oct 11, 2010)

96 f150 and it's a small vacuum hard tube to move cabin heat blend door. It looks like about 1/4" from outside. I need to splice- replace the part that's crumbling. I wrapped electrical tape around it but now feeling that's not good enough. 

Plan is to cut to the tube that's still good and use a barb fitting to splice. I have a barb coupler but it's hole is only about 1/16". So I'm wondering if vacuum works even if the tube hole gets reduced. The reduced fitting is about 2" long. Would the vacuum work just as well or does the reduction somehow interfere with air travel? Again, it's only about 2" where the air travel would be choked.
If no problem, does it work about the same throughout the vacuum system in the car?


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## Windows on Wash (Aug 30, 2011)

It will work.


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## DexterII (Jul 14, 2010)

I agree, it will work. I would second guess the tape too because it'll invariably leave a gap someplace. As far as "working the same throughout the system", if you mean can you run the smaller line all the way back to the source, probably, but I wouldn't because the smaller the line the smaller the radius and my concern would be pinching it down too much in the bends.


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## ron45 (Feb 25, 2014)

I would replace the whole thing.

Once it starts cracking it won't stop


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## Windows on Wash (Aug 30, 2011)

Might need to run some Fuel Injection cleaner.


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## carpdad (Oct 11, 2010)

Turns out that vacuum hard tube had inside diameter of about 1/32. I used the barb. Using 1/8" i.d. silicone tube to replace the rotten part and reusing the old rubber connector. Other end, I slipped the silicone tube over the good portion of the old hard tube. Secured them together with shrink tube but not sure if the shrink tube will work well, hard tube is about 1/8 od and the silicone is 3/8 od. 



Is there some source for high quality shrink tube, ones that are more than 3:1 shrink ratio? Or rubber connectors? Vacuum lines in the truck use many rubber connectors, esp to transition from hose to the nipple on the parts. These need to be fairly thick walled also for vacuum uses, so they don't collapse (am I thinking too much on the collapse part?). 



Again, thanks to all. I will try techron fuel system cleaner, but is there some reason for recommending it? I was using lucas fuel cleaner, every 2-3 fuel fills. Techron says it will restore system seals? Could it help with injector o rings and such? Even if temporary, I'm willing to try it, although the 24 yr old truck probably needs a lot of overhaul.


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## DexterII (Jul 14, 2010)

I don't know if you'll find a single piece of shrink tube that will cover that much ground, but if you have an assortment you might try stacking it, smaller one on the small tube first, or maybe a couple of progressively larger ones to get closer to the other one, then a larger piece over the whole thing. I don't know, don't remember trying to build anything up that way, but might work so I'd try it. In fact the reason my earlier post was edited is because I initially suggested shrink tube, but then decided it sounded like pretty tight quarters, didn't know if you could safely heat it, so edited that part out.


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## mark sr (Jun 13, 2017)

My wife used to have a Sable with the same type of line for the windshield washer. I just cut out the bad and slid slightly bigger vacuum line over it. Worked great for yrs.


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## carpdad (Oct 11, 2010)

There's enough room for heating. Stacking is a good idea. I may have to get a kit and with adhesive. This vacuum tube goes into the cabin and to the blender door controls, I think. It is part of a thick harness, other tubes and wires.
This hard tube is literally dusting off its skin. Inside the harness its still pliable and a firm plastic, but where it was exposed, it has shed the outer plastic and down to less than half of the original diameter. I could scrape the outside off with fingernail. It's bit odd that other exposed hard tubes feel fine, just this one. It's furtherest away from the engine as well. But I know now that these hard tubes still have life and if they deteriorate, they go slowly from outside - for my car, anyway.


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## DexterII (Jul 14, 2010)

Ya know, I don't want to get into the politics or anything of it, but the wife and I are in that age group where covid may be of more concern so my mind tends to head straight to resolving as many things as possible with what I have on hand in order to avoid a trip to the store. So my first though with stacking the shrink tubing was that you probably had an assortment and could just grab it off you own shelf. But if you have to go out and buy some additional sizes I would go to your local auto parts store, and first see if maybe they have an adapter just the size you need. Those revolving display racks are usually full of skin packed doodad's that sometimes don't quite fit the bill, but this seems like something you might find there.


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## carpdad (Oct 11, 2010)

Thanks for the idea. None of the virus stuff is political for me. I mean, we can push the rubber ducky into the water but it pops back up.:smile: I don't see what philosophy is in that.:smile: Also realistically, I don't see me getting a vaccine (if it works) anytime soon, maybe by the end of 2021, so except toilet paper, no use getting things in order.:smile: Autozone has been disappointing these many years. It has obvious things but nothing that can adjust and adapt. But will give it one more shot.


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## DexterII (Jul 14, 2010)

I understand, was just typing what was on my mind as far as not making any more trips than necessary and with so much controversy today figured I'd throw that in so someone didn't come along and call me stupid. As far as which store though, my opinion anyway, Autozone and other chains may be fine if you want an alternator or whatever for a specific vehicle, but not so much for items that they can't quickly look up on their computer, So if you have any around I would go to one of the independents. That's what I do, fortunately have a few of those left in the area, and if you can't find what you want on the rack they will usually at least know what you're looking for, may have to order it, but that's okay too if it does the trick. Some of the chains, I don't know, but sometimes suspect they may have it in a bin under the counter and just don't care enough to try and help.


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## cakaup (Jul 7, 2020)

A piece of rubber hose slid over the hard plastic works great.


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## carpdad (Oct 11, 2010)

I think this will work: shrink tube over the old vacuum tube, which brings up the tube diameter, which fits tight into the silicone tube. It was a mistake trying to bridge the two with one shrink tube. The trip was wasted.:smile: Advanced auto, this time, and the counter people obviously didn't catch on to what i needed to do.


Turns out I had 2 sets of shrink tubes. 2:1 and 3:1. I was buying these as i was learning and I think 3:1 is better choice. Also, when picking a size, better if the tube is little larger. I found that larger shrink tube will shrink with thicker wall. 



Thanks all for ideas.


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