Solved Vacuum line solution!

[natenkiki2004]

When I got my Exploder I had vacuum leaks that I found in the hoses and fixed them. Ordered new rubber boots from the local parts store and cut out holes that had been worn by rubbing. Fast forward a few months and the boots were cracking again and I found more holes in the plastic lines.

Annoyed, I set out to solve this with some silicone tubing. I went out and measured the various vacuum fittings and found the smallest one (air box) and got some silicone hose based on that fitting. I purchased 10 feet of 3/16" (5mm) ID silicone tubing and went to work:

https://dl.dropboxusercontent.com/u/464376/vehicles/1991 Explorer/Pictures/IMG_20140613_173115.jpg
https://dl.dropboxusercontent.com/u/464376/vehicles/1991 Explorer/Pictures/IMG_20140613_173122.jpg
https://dl.dropboxusercontent.com/u/464376/vehicles/1991 Explorer/Pictures/IMG_20140613_173135.jpg

I like the look, the ease of working with it and it seems to be the right size for most all of the fittings, even stretching to fit the trans vacuum line. Unlike rubber, I don't feel like it's going to crack if I stretch it over a fitting.

My only gripe is that it doesn't feel quite tight enough on the air box thermostatic control valve. I think it will work ok but if you're thinking of trying this, 5/32" ID silicone hose might be worth a try. All the other fittings felt great, even the fuel pressure regulator.

Also, worth noting is that I had 2 left over vacuum ports on the manifold. I'll be using one later for a vacuum gauge but for now, I just cut a short section of hose and hooked them to each other so I don't have to use a cap (which often crack too soon).

All in all, $10 and a little bit of time. I'm very pleased and best of all, don't have to deal with the plastic lines again.

 

[Got Trq]

Hmm... Good idea! I need to replace the one on my FPR, it keeps coming off, the rubber boot part just doesn't really hold itself on very well anymore.

 

[natenkiki2004]

Exactly. Mine was easy on, easy off. The factory rubber is excellent in that it doesn't crack but it gets hard and isn't as tight as it once was (joke in there somewhere). Aftermarket boots lasted all of a couple weeks before seeing stress cracks in them. Months later there weren't any holes but it still doesn't inspire confidence.

The silicone is unbelievably flexible (think spark plug wires) and is a lot more forgiving when you get 1 size for various size ports. Silicone is silicone but rubber can have different blends and temperature ratings.

Also, 10 feet allowed me to do all the vacuum lines up top plus one into the cab for a vacuum gauge with about 8" left over.

 

[SLewis]

ok so where did you get the tubing?


Steve

 

[natenkiki2004]

From eBay seller first.racing:
http://stores.ebay.com/YJRacingParts?_trksid=p2047675.l2563

Here's the specific listing:
http://www.ebay.com/itm/251183546221?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

 

[Got Trq]

I wonder if the stuff I use for my paintball gun would work...

 

[SLewis]

Thank you.


Steve

 

[natenkiki2004]

Thank you.


Steve

Not a problem This site's been a valuable resource to me, I try to give back when I can, even if it's something small.

I wonder if the stuff I use for my paintball gun would work...

As long as it's the right ID, silicone is silicone. I will say I like the stuff I got because it's incredibly thick-walled unlike other silicone tubing I've gotten. It feels beefy and would take forever for something to rub through it unlike the thin factory plastic lines.

 

[Got Trq]

So my guns use Polyethylene tubing, I wonder how the different materials would hold up. Doing a little research it looks like Nylon tubing would also be a good option.

 

[natenkiki2004]

As far as I know, silicone has the highest heat and electrical resistance and long life. It's why the stuff is used in cop cars and spark plug wires.

 

[Got Trq]

Yeah, I think nylon would be too hard to use.. It's not the most flexible stuff, but it's supposed to be very resistant to oil and such.

 

[x5050160]

Hey natenkiki2004, I searched the ebay store you linked to earlier and found this http://www.ebay.com/itm/Silicone-Vacuum-Hose-2-3-4-5-6-8-10-12-16-19-22-25mm-High-Performance-/261191598660?&_trksid=p2056016.l4276
Do you know how thick the wall of that tubing you used is? I want to ask the seller the thickness and compare it against what you have. Also do you forsee any issues with the hose collapsing?

 

[natenkiki2004]

That is the same thing, just more colors and sizes available. Scroll down a bit and find the chart, anything between 0.08" and 15/32" has a 3mm wall thickness, as does the stuff I got. I don't think it will collapse. It's very flexible but the wall is thicker than I thought it would be. I would be more concerned with regular rubber hose collapsing over tight bends and with age than I would with silicone.

 

[natenkiki2004]

In the process of going through and updating my more informative posts with images attached directly to the forum, I found this thread again and wanted to report that these lines are still working great. The only "issue" I've had is that I cut a small piece for the evap to throttle body connection and that piece has discolored slightly. It hasn't cracked or split though and it at least tells me that my evap system is working.

Here's some newer pictures after a lot of other work has been done:

 

[Rhett]

your 91 has a different intake tube than my 94. Yours is smooth on top mine is ribbed on top like the sides.

Looks like you have A/C delete? And those look like Motorcraft plug wires?

I have replaced vac lines piecemeal over the years but I need to go in and do what you did. Especially since the silicone is holding up. When my vac modulator was bad it leaked tranny fluid into a couple of them, like the BB hose, and I still haven't replaced them. It's still slimy.

 

[natenkiki2004]

Good catch for the "Differences" thread, the air tube. Ford used a 3-piece early on then moulded the whole thing as a solid unit in later years. I swapped my 1994 tube to the 1991 just to prevent any leaks.

I did do the AC delete, I've got a thread on it somewhere...
http://www.explorerforum.com/forums...lacing-the-blower-box-with-non-ac-box.414311/
Those aren't Motorcraft plug wires, they're Napa/Belden Premium wires.

Honestly, this vacuum hose was one of the better bang for buck upgrades to the Explorer. Up there with new shocks & tires in my opinion.

 

[DENZILH]

Very helpful this post-I also have leaky vacuum lines. Thank you!!

 

[92exp4x4]

I wondered about the blower housing, To my knowledge A/C was standard on the Explorer. None came out of the factory without it. Makes it a lot easier to work on, and a great spot for your add-on coolant filter?

 

[natenkiki2004]

I wondered about the blower housing, To my knowledge A/C was standard on the Explorer. None came out of the factory without it. Makes it a lot easier to work on, and a great spot for your add-on coolant filter?

You know, everybody says that but the previous owner of my Ex never did any AC work (aside from yanking the compressor) and both my AC box and dash sliders are aftermarket. The blower housing was aftermarket with a WYNN sticker on it. I have a hard time believing that the box needed to be replaced if it had the AC system serviced, the OEM ones are very sturdy. If it was serviced, it would have had to have been before 2001 which makes whole system replacement even more unlikely. The dash controls are different too, I have to slide the air control all the way left to turn on AC. It's my understanding that the factory units, you push the fan control button in which is how it works on my 1994. This info leads me to believe that my 1991 didn't come with AC or was an early model that the dealer outfitted in the aftermarket.

 

[92exp4x4]

Very possible. What is the build date of your truck? I wonder if maybe it was a special kit for some special use? Was it owned by the state or a business when new? It would be interesting to find out why.