Black and Grey Water tanks leaking

[Keith Murray]

I have a '78 Winnebago Chieftain and both the tanks have cracks coming from where the bolt anchors are in the tanks. The tanks seem like they are nylon, but was told they are not. Any ideas how to fix the cracks? Plastic weld? Some kind of tape with a covering of sealant? I will remove the old hanging brackets and make something new up, so could cover those bolt holes.

Any info appreciated.

Thanks

[LABikermamma]

try Fiber Fix...new product like wrap on a broken arm....cast material only made out of Fiber glass and hard glue.   You must READ the directions. find it at Home, Lowes, QVC!

It's worth a try....otherwise it's drop the tank and put a new one in.

[John "T" Nordhoff]

 While I've sanded them then used an epoxy like JB Weld, I think its best to buy the regular RV tank solvent weld/epoxy like I only see sold at RV dealers made especially for EITHER the black ABS black water or the white plastic fresh water tanks. Be sure to really clean then sand and rough up the surfaces for best adhesion and seal. Its actually best (my opinion and whats worked best for me)  to use a small side grinder/sander etc (go very very easy now) to make a very tiny valley where the crack was which allows for more surface area and a stronger seal..Before replacing hang straps I think I cut up an old inner tube or something to place a thin piece of rubber between the tank and straps if at all possible. In addition to take some of the weight and stress off the hangers I take a piece of plastic coated 1/4 chain and hang it under the tanks bottom center and use a turnbuckle etc to put just a slight tension under it so once the weight pulls the bottom down it absorbs some of (not all or too much) the weight.

 John T

[Keith Murray]

Thanks John T

I will see what is available locally here in Canada. Both my tanks are attached to each other and replacement is not a viable option, so I will try to repair and support differently than the bolts going into threaded inserts in the ends of the tanks- that is what caused the problems. Cracks are running down from the threaded inserts and they leak at about 2/3 full.