Repairing the Freshwater Tank

5/26/2022 – Good Sam Extended Service Plan

Cracks or holes may appear in the freshwater tank if severe impact or abrasion is encountered. Overfilling the tank may also create stresses that may lead to a rupture (and damage to the surrounding compartment). After many miles of travel, the constant vibration may cause a crack to appear.

Repairing a freshwater tank can be one of the most expensive RV repairs, and that's why it's a good idea to have your RV covered with a Good Sam Extended Service Plan.

How can you repair an RV plastic freshwater tank?

Plastic tanks can be repaired with a special epoxy resin and fiberglass patch following these steps:

Drain the tanks so the area around the crack is dry. If the crack is in an inaccessible area, the tanks must be removed.
A small hole (1/8- in diameter) should be drilled at each end of the crack. This prevents the crack from propagating from under the patch you will apply.
Sand the area around the crack until the tank surface is roughed up to allow a good adhesive bond.
Cut a fiberglass patch about 1 to 2 inches larger than the crack in all directions.
Mix the epoxy resin with its catalyst. After the catalyst is added, there are only about fifteen minutes of working time before the resin “sets up” and starts to harden.
With a small brush, dab a layer of resin over the area that was rough-sanded. Then lay the fiberglass-cloth patch over the resin. Pat the patch with the brush until all the fiberglass is soaked with resin.
Add more resin to the patch area until it takes on a glossy appearance and the cloth fibers are covered.
The resin will become tacky in about fifteen to twenty minutes and will fully harden in a few hours. It's best to wait twenty-four hours before filling the tank with water and inspecting for leaks. (Note: These kits work best on cracks up to 5 inches and holes 1 inch in diameter.)

Some plastics – especially larger repairs – can be welded using a hot-gas procedure and special plastic welding rod. This is a specialized method that is used most often in plastic-tank manufacture. Many RV repair shops are equipped to perform this type of repair.

How do you repair stainless steel or aluminum freshwater tanks?

Metal tanks, stainless steel, or aluminum should not be repaired with fiberglass/epoxy method. The best way is by welding. Since stainless steel and aluminum are difficult to weld, they are best repaired by a professional with gas-tungsten-arc (sometimes known as Heliarc or TIG) welding. The tank should be removed from the RV before welding. Tanks that have been damaged by freezing can be repaired if the damage is not too severe. Permanent bulges, long cracks, or split tank seams warrant tank replacement. Although temporary repairs may be made, this type of damage often will cause the tank to fail in a relatively short period of time. If you need to replace a metal tank, consider making the conversion to a demand system using a polyethylene tank.

If you're in need of an RV repair or maintenance, you can make an appointment today at your nearest Camping World Service Center.

Livingston , B. (2002). RV repair & maintenance manual . (4th ed.). Ripon Printers

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