Repair drip in PCV pipe

[Challenged]

I am looking online (youtube) and they cut out the section and put in a new one. Is there a way to fix a leaking PCV joint without cutting it out? It is leaking in the large tank drain pipe.

[pjhansman]

Are you sure it's PVC? Possibly PEX line?

[Blueswede]

Is the leak in the drain line? A picture would be helpful.....

[allmi01]

Drain lines on RV's are ABS not PVC, You should not try to mix the 2 (and yes, you can, but its not recommended as the glues used are different between these 2 type of pipe and don;t bond properly).

You can try one of the epoxy putty pipe and tank repair products, Depending on what the underlying issue is, it may correct your problem. Its worth a try for a few dollars. If its doesn't cure your issue, then you have no choice but to cut out and replace the bad pipe / fittings.

Mike

[hankpage]

Challenged, Mike is 100% correct on the use of the proper cement. They do make a product that will work on all three and combinations of them but it will not give as strong a bond as the individual glue made just for ABS.
Your description is vague but I assume you are talking about the three inch drain from your black tank. A leak at one of the fittings (since there is no pressure) can sometimes be repaired with a good drying and cleaning (acetone) and a liberal application of the ABS cement around the joint or an epoxy compound made for pipe repairs. If your leak is from the point where the pipe enters the tank, I think you may want to consider getting a professional to do it. JM2¢, Hank

[bsmith0404]

as others have said, the correct glue should do the trick. you could also add a cut piece of rubber over the glue spot after it dries and secure with a hose clamp for a little extra security/piece of mind. similar to a radiator hose repair patch.

[Quiroule]

The best way is to mix a good amount of ABS shaving with acetone until you get a manageable paste. Then apply it to the leak right away, it melt to the ABS and makes a very good bound. Try it first on a piece of scrap.

Good luck.

[Challenged]

The leak was under the shower in the ABS elbow where it was threaded. I made a newbie mistake and didn't dump soon enough, and the elbow filled with water. It soaked the whole compartment the elbow was in. The carpet got soaked and it was leaking under the trailer. I ended up putting in a rubber gasket and then leaving the door to the compartment open in the sun for 2 days. It still leaks a little but if I don't fill up the pipe I think it will be okay.

[Wes Tausend]

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I note someone recommended mixing ABS shavings with acetone to produce a thick paste. That is no longer necessary since Menards carries three low cost variations of ABS cement: thin, medium and thick. All ABS cement has some ABS dissolved within it and becomes solid ABS plastic when the solvent evaporates. The solvent also partially dissolves the tank surface and all dries as one piece.

My blackwater tank cracked under where the outlet was cemented to the tank because I left a campground in a hurry, with a nearly full tank, to attend an emergency surgery for my son who was in an accident (he's doing fine). The tanks on my vintage 2004 TT are secured only by their top edge with no support straps underneath. Imagine a tote being held by two lengths of iron channel along the top edge perimeter of each side. These tanks are economically made like this with a glued on cover similar to the flat cover snapped on a tote.

This method is normally adequate to support the loaded tank at low speeds until it can be dumped, but having skipped dumping, I later hit a rather rough bridge apron at high speed which over stressed the 32 gallon assembly. Since water weighs about 8+ pounds per gallon, a considerable amount of inertial weight tends to distort and bulge the tank during high G impacts. This is especially true of the deep drain end since the sloped tanks have more liquid near the drain.

The drain assembly includes an ABS wye-pipe, and both tank slide valves, which together allow the greywater to drain out the same single outlet. My wye-pipe was self-supported, and close to the greywater tank, but about a foot away from the blackwater tank. This extra length-leverage allowed the blackwater drain pipe attachment to flex the tank during high bump impacts. That in turn, cracked the tank just below the pipe attachment, just where the ABS plastic is stretched the thinnest during hot vacuum forming (The correct way to vacuum form is to momentarily inflate the plastic sheet to stretch it evenly and then draw the more evenly stretched film down with vacuum to fit the mold. Many plastic vendors do not do this extra step).

I used the medium ABS cement and think it is quite possible the thick stuff may be too thick. The reasoning is that it is necessary to force the ABS cement into saturating some sort of reinforcing fiber (I used fiberglass tape used for drywall or plaster veneer joints). I didn't try the thick stuff but I would definately have the medium on hand if I did. I used three layers of fiberglass tape cut at different sizes to taper the lump of layers. I applied them consecutively without pause since the cement dries very fast anyway. Wear rubber gloves and old clothes as it is hard to get goop to drip upward.

While I was down there in the mess, I ran pipe hanger strapping around the bottom of the tank to give further support in case I ever have to skedaddle without dumping again. I cushioned the strap with surplus pieces of nylon seatbelt, since I could no longer find the old cotton belt webbing that used to cushion the gas tanks on old cars. The cotton webbing was once popular to repair canvas conveyer belts on farm machinery.

One other problem was noted. The angle iron braces used for fastening the final belly enclosure plastic were touching both the black and grey tank bottoms. They are welded to the frame presenting a flat panel mounting bottom and the angle straight up. The upward sharp angle edges had nearly worn through the tanks. I added a pair of split 1/2inch PVC sections, covered with split auto heater hose, spread and slid over the edge of the iron. It pinches on to the angle iron and holds its place well. This blunted the sharp edge that was cutting a slot in the bottom of my tanks. I used plastic PVC because it was what I had on hand, but I would have used steel conduit if I had it handy. The heater hose was just some surplus that I had, that gave the tank a softer rest to delay wear-through since the tanks bounce against it.

Wes
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