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Cubey · 08-29-2012, 11:14 AM

My 1978 Dodge Xplorer appears to have black pex tubing in it. Was pex around in the late 70s? A short piece near the pump reads vanguard plastic(s) (it's cut off before the word plastic(s) finishes).

Or is that some make-shift setup similar to pex that someone did? The hose coming from the water pump to the tank looked like it was poorly redone by someone about 15-20 years ago (the hose was badly hardened) and was installed with a bad kink in it. I doubt Xplorer would have installed it that way.

I've attached a photo to show what it has.

I was considering redoing it with new but I'm better off just sanitizing it if nothing is leaking... why fix what isn't broken? So much of the tubing is hidden... it would be murder to try to replace a leaking section in this van.. so I am hoping the plumbing is all ok. I (partly) winterized it (drained the hot water heater, blew air into the lines from the city water hookup).. except the dang fresh water tank, i forgot... due to the plastic drain valve breaking but.. it had water in it still today (very nasty.. but still) so it didn't burst.. there wasn't much water in it. Plus we had a mild winter.

Aside from around the water tank where I am having to replace the drain valve and hose, replace the air vent hose, clean large corrugated the gravity fill hose, replace the line between the tank and pump (will use pex).

I just bought this van earlier this year and haven't used it any so I am in the process of getting it ready for use.

Dogpatch · 08-29-2012, 11:32 AM

I think it was all Poly B back then. Although, the photo looks more like irrigation pipe.

Cubey · 08-29-2012, 11:44 AM

That is what is throughout the van so it's most likely not a hack job someone did.

I guess I will leave it be if it's not leaking. It's a somewhat flexible like pex is.

Hmm.. I just thought to check wikipedia:

"The first PEX material was prepared in the 1930s, by irradiating the extruded tube with an electron beam. The electron beam processing method was made feasible in 1970s but was still expensive. In the 1960s, Engel cross-linking was developed. In this method, a peroxide is mixed with the HDPE before extruding, the cross-linking taking place during the passage of the melted polymer through a long heated die. In 1968, the Sioplas process using silane was patented, followed by another silane-based process, Monosil, in 1974. A process using vinylsilane followed in 1986."

So it seems pex did exist in the 70s. But it may be Poly B like you said... but I best leave it alone if it's not leaking I guess.

Cubey · 08-29-2012, 03:05 PM

Hmm.. it wouldn't as bad to replace all the lines as I thought, if comes down to it.

I had to just trace how the lines run. It would be somewhat hard but not impossible.

And I found a pop rivet tool stashed under a drawer I pulled out to look at how the plumbing ran and to vacuum out the area. *lol*

Senior Chief · 08-29-2012, 03:11 PM

AFAIK, it was all poly butyl back then (through into the '90s, in fact). I thought it was all gray, but maybe they made it in black as well.

Seems unlikely your manufacturer would depart from industry standard in that way- pretty much every RV made in a given era uses identical materials.

Cubey · 08-29-2012, 03:15 PM

Quote:

Originally Posted by Senior Chief

AFAIK, it was all poly butyl back then (through into the '90s, in fact). I thought it was all gray, but maybe they made it in black as well.

Seems unlikely your manufacturer would depart from industry standard in that way- pretty much every RV made in a given era uses identical materials.

So now the question is.. what was the standard in the late 70s?

I had a 1967 Shasta trailer but that was made back when they still used all copper lines for the water.

RedneckExpress · 08-29-2012, 07:30 PM

60s-70s, Copper and Galvanized steel, with some odd instances of polyethelyene. 80s - early 90s, Polybutylene, mid 90s and on, PEX.

Looks like Polyethylene pipe

, it too clamps in the same fashion as polybutylene did.

Cubey · 08-29-2012, 08:10 PM

If only I knew for sure.

I think I am going to just replace it all anyway with new red and blue color coded pex. It will cost about $125-150 including the crimp tool and a day's work.

In my opinion, it's a small price to pay for piece of mind that the system doesn't have any splits from lack of winterization. And too... I'll know for sure if it's Pex or not.

PeterS · 08-31-2012, 05:12 AM

I'm replacing all my grey plastic, pressure-clamped pipe with flexible boat hose. All straight runs, very few joints. I'm putting all the connections where I can get to them. While I was ripping out the old pipe, one had a screw through-it from the original construction, 22 yrs ago! Once you pull out that nasty carpet all kinds of sins appear.

RapTaz · 09-04-2012, 10:02 PM

Quote:

Originally Posted by Cubey

I think I am going to just replace it all anyway with new red and blue color coded pex. It will cost about $125-150 including the crimp tool and a day's work.

In my opinion, it's a small price to pay for piece of mind that the system doesn't have any splits from lack of winterization. And too... I'll know for sure if it's Pex or not.

A friend and I had a conversation about me replacing some of the tubing in my RV with PEX. He has a decent amount of experience replacing plumbing lines with PEX. His suggestion was to use Flair-It fittings rather than purchasing a tool and doing the crimps. His reasoning makes sense to me. For one, emergency repairs are much easier, no need to have the crimp tool. Also using a PEX crimp tool requires room-it is not easy to open one in the tight quarters of an RV-the Flair-It fittings will work in tight quarters.

Just thought I'd throw this out for consideration.

Glenn

Mike Thomas · 09-05-2012, 05:09 AM

Many would argue that the polybutylene was a better pipe than the pex. I have installed miles of both. The poly was much more flexible than the pex. The only reason you don't see it any more is a lawsuit over leaking fittings, and the only manufacturer of the resin, who got caught up in the lawsuit, decided they were going to just quit making the resin available for pipe production.

You can still find it in the plumbing section. It is still used to make the risers, short pieces of pipe that connect sinks and bathroom stools from the shut off valve to the actual appliance. They still use it there because it is very flexible and works better than pex.

I wouldn't waste my time replacing all of my polybutylene piping with pex, as you would be replacing a superior product with one that was of a lower quality. If it isn't leaking, there is nothing wrong with it.

As side note, I have seen homes freeze up at minus 40 degrees for two weeks. We would replace a few valves, but never had to replace any pipe, it just expands a little with the ice, but never broke. That holds true for polybuteylene or pex.

Cubey · 09-05-2012, 07:37 AM

@RapTaz - If I can't fit a pex tool into the area, then there won't be space for a gatorbite fitting which I assume is what you are referring to. Those fittings are very large vs normal ones. But they might be useful in some places.

@Mike Thomas - If the Poly B fittings are prone to leaking for no good reason, then I'm not sure how it can be considered superior? And how do you find it in the plumbing section if the company doesn't make it for pipes anymore? I'm badly confused on that one. *lol*

I guess I may at least try it with water pressure and see if it's leaking any right now. If it is in any place at all, I will replace it all with pex.

Mike Thomas · 09-05-2012, 04:00 PM

The reason for the lawsuit was not faulty pipe. As in many legal situations, the attorneys drew everyone even remotely associated with the product in to the lawsuit, to get as much money as possible. The fault was with the plastic fittings that were used to connect the pipe together. The brass fittings caused no problems at all. A FEW of the plastic fittings failed because of high pressures, a FEW failed because of instances where they were used for constant recirculation applications, SOME failed because of faulty installation techniques, and most of those were in moble homes, and they failed in the first few years.

If you have this product in a motorhome: a)your probably don't have high pressure on a daily basis, b) no constant recirculation situations in a motorhome, c) if it hasn't failed by now, it was installed correctly.

You can fix it with "shark bite" fittings, or any other of the "universal" ones. It is a better product than pex, in my opinion, and in the opinion of many others in the plumbing field.

Take this information and apply it as you see fit for your situation.

Cubey · 09-05-2012, 04:43 PM

Thanks for the explanation. Mine seems to have all copper(?)/brass fittings from what I have seen.

Who knows what kind of pressure past owners put on it. I will be using a brass RV water regulator on it.

I don't know if the water system has any burst places (more likely from lack of winterizing, than it being Poly B from the sound of it) so I will just have to see how it holds up when I hook a hose to it.

I do at least need to replace the city water hookup itself. It is partly broken somehow and loose. But that just threads on to a brass fitting on the end so that won't be a big deal to replace if all of the rest of the system is sound.