Black Tank Leak - questions

geotex1 wrote:

Ed9824v wrote:

EMD_DRIVER wrote:
I had a severe black tank leak, on a travel trailer that we used to have. Instead of buying a kit, I went to Lowes and bought a can of ABS cement and a short piece of ABS pipe. I used a reciprocating saw to make several cuts along the piece of pipe. I gathered all the cuttings and put them in an old cup. I poured some of the ABS cement in with the trimmings and stirred it up. I had already cleaned the crack as best as I could and scuffed the area around it with a wire brush. I put a couple pairs of disposable gloves on and spread my weld in and along the crack. That was 5 years ago and that tank has not leaked since.

this maybe the answer if it is ABS tank, I do read that some of the newer tanks may be polyethylene this procedure will not work with this cement mix. my freshwater(polyethylene) tank leaked and I paid someone to fix it with some type of adhesive, it lasted 1 year. then leaked, I took it out again and welded it up, I took an old big solder iron from my dad and silver soldered a stainless steel disc to the bottom and welded up the tank and it has been good for a couple of years now and has about 118 gallon of water in it right now. I now have fixed other plastic items and will melt in metal screen door wire for extra support. I have gotten pretty good at it not so pretty but strong.

Polyethylene tanks are cake to repair! As you found, it is a thermoplastic. Proper welding is to use an extrusion welder with filler rod. You'd be surprised how easy it is to find someone that can do this for you! Your method works, but you are locally thinning and altering the properties of the polymer a bit.

When I checked for a repair shop in los angeles there WAS one and they moved out of state, I do have a hot air electric heat welder that you feed the rod into that I found hard to control, I purchased poly rods as filler and built up the area and what I did not mention, I also added a lot of extra support under the tank.