Internal Fiberglass potable water tank repair

External Since: Jul 14, 2005 Posts: 123

I've got a tiny hairline crack in an integral fiberglass water tank
that I need to repair. So far, folks have suggested epoxy, JB weld,
polyester resin, etc., but no concensus has appeared. Any suggestions?
Any reason not to use aquarium type silicone caulk? Anything else I
haven't thought of? TIA.

External Since: Jun 22, 2003 Posts: 434

On 14 Jul 2005 14:44:34 -0700, "Keith" <keith77720032003 RemoveThis @yahoo.com>
wrote:

>I've got a tiny hairline crack in an integral fiberglass water tank
>that I need to repair. So far, folks have suggested epoxy, JB weld,
>polyester resin, etc., but no concensus has appeared. Any suggestions?
>Any reason not to use aquarium type silicone caulk? Anything else I
>haven't thought of? TIA.

With zero experience at this repair application,
here is my considered (!) view:

1) Drain water tank.
2) Paint seeping crack with alcohol.
3) Dry
4) Repeat alcohol application.
5) Ensure exterior tank near crack is keyed with emery etc.
6) Blow warm dry air into tank 1 hour before dark.
7) Paint crack with fluid grade epoxy.
Cool

Next day, apply epoxy tape at site of crack.
9) Pressure test tank (at low, low pressure)

Enjoy....

Brian Whatcott Altus OK