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Plumbing problems

PostPosted: Thu Aug 07, 2008 9:03 pm
by dreadcptflint
Well, I took my Mobi out for a quick excursion and sprung a serious leak in the plumbing. It sprayed all over my electrical every time I turned on my sink and I am not very happy about it. They used a heck of a lot of pipe clamps to secure all the tubing together and well that just didn't get the job done. Does anyone have any pictures of their plumbing or any suggestions on how to fix the system to take more than a couple of bumps?

:shock: :x :shock:

PostPosted: Thu Aug 07, 2008 10:40 pm
by Juneaudave
How much pressure is the pump putting out? Most of the RV water pumps I've seen aren't that high of a pressure that a clamped fitting wouldn't work...
:thinking: :thinking: :thinking:

PostPosted: Fri Aug 08, 2008 6:54 am
by Lgboro
Clamps even work on car radiators that operate under very high pressure and temperature so I would think clamps should easily hold under the requirements of teardrop plumbing. You could use two clamps if you are still unsure after checking them to see that they are tight. I would use the automotive clamps that screw to tighten instead of a spring type clamp.

PostPosted: Fri Aug 08, 2008 7:45 am
by mechmagcn
Lgboro wrote:Clamps even work on car radiators that operate under very high pressure

Uh, I think you need to rethink this one. The highest pressure cap that I know of for an automotive radiator is 16 PSI. RV water pumps are generally set for 45 PSI.
What sort of tubing is used for the plumbing in question? If it is Pex tubing, no amount of tightening of a screw type clamp is going to hold it. This type requires a copper ring and crimping tool. If it is the clear, reinforced tubing, then hose clamps should be sufficient.

Re: Plumbing problems

PostPosted: Fri Aug 08, 2008 9:44 am
by Dale M.
dreadcptflint wrote:They used a heck of a lot of pipe clamps to secure all the tubing together and well that just didn't get the job done.
:shock: :x :shock:



Umm..... Why a "heck of a lot of clamps"..... Seems to me for most application(s) rigid/threaded connection for plumbing would be better.... For water connections (pressure) either soft copper tubing with flared connections or rigid steel piping with flex connectors just like under kitchen/bathroom sink's at home...

http://www.rensup.com/Sink-Supply-Lines/13871.htm
http://www.doityourself.com/invt/2540011

Lots of variation of connectors on ends of "sink supply lines" something should fit your applications...

Dale

Quick picture

PostPosted: Fri Aug 08, 2008 10:50 am
by dreadcptflint
Image

Right now the primary culprate is the small clear tube gowing from the bottom to the top. It runs from the pump to the facet. I already tightened a couple before I went out and checked for leaks when I sanatized the line. (There was only one that I tightened up).

As you can see every hose has a clamp at both ends. Should I go to a more plumbing type model or just tighten down the offending tube and hope that it doesn't loosen up again?

PostPosted: Fri Aug 08, 2008 12:37 pm
by madjack
I would try tightening the offending tube before getting on with a drastic rebuild.................................... 8)

PostPosted: Fri Aug 08, 2008 1:40 pm
by alffink
From your photo, I can not see what type of a barbed fitting the clear tube is connected to. it is also difficult to see, but it does appear that the
clear tube is deforming over the fitting, making it appear that the fitting may be too small for the tubing, which in turn as you tighten the hose clamp the tubing actually tries to wrinkle as the clamp tightens forming a small but efficient leak path. lossen your hose clamps and make sure that you have to work the tubing off the fitting, if it just falls off the fitting is too small. :thumbdown:

PostPosted: Fri Aug 08, 2008 1:54 pm
by bobhenry
I agree with Al most barbed fittings will seal on the poly tube without excessive clamp pressure the only reason to spray is a hole in the tube or the tube is simply to large of a inside diameter for that size barbed fitting the easy fix is to just install a larger barbed fitting 2-3 $ at a good plumbing supply place.

PostPosted: Fri Aug 08, 2008 5:20 pm
by mechmagcn
Actually if it was mine, I would do away with the poly tube and use a piece of the reinforced tube (of the correct size) like was used for the vent line beside the tank fill. While the poly will hold the pressure of an RV pump, it is easily deformed with a hose clamp, it really works better with compression fittings.

PostPosted: Sun Aug 10, 2008 3:22 am
by ARKPAT
Yes and I have had problems with application of clear tubing like shown expanding when warm or ALOT when it get HOT ( Not neccessarly the water but heat in an enclosure ). No matter how tight you get the clamps the tubing will expand and loosen at the fittings. I'm with Jeff on this one. :thumbsup:

Pat

PostPosted: Mon Aug 11, 2008 11:19 pm
by mobile camper
We went through the same problem with our Mobi but with other fittings. that is when we decided to elimate the pump and sink and install a manual foot pump with a hose that takes suction from the fitting on the side of the tear. we have had outstanding results. :thumbsup: we have pics in our album.

Steve G

Update

PostPosted: Wed Aug 13, 2008 5:20 pm
by dreadcptflint
I got a little time today. (After chugging some soap thanks to my little dude). I replaced the clear tubing with some reinforced. It was a whole $.60 a foot at the hardware store. It should hold now. If not then I will spend the couple of bucks to get some better fittings. (I prefer brass over plastic every time). I gave it a quick tester and it appears to be working with no drips. The real test will be when I take it out and hit a few more bumps.

PostPosted: Sat Aug 23, 2008 12:32 am
by NW_Subie
In my discussions with Justin I let him know about the problems you've had. He indicated that they had not had problems in their testing but appreciated the information. He said he would recommend changes to the tubing. The company seems receptive to finding solutions.