On Sun, 8 Jun 2014 15:28:40 -0700 (PDT), wrote:

Sometimes cyanoacrylate in a plastic crack works - to my surprise. I
cant see it coping here but might help support the repair patch a bit
more.

Guess it depends on the size of the crack/hole. If it's a really tiny
pinhole, emptying letting dry, warming the area, and appling liquid
cyanoacrylate might work as it'll get drawn in by capillary action.
Might be enough to bung up the hole but I doubt it will take much
movement, cured cyanoacrylate is fairly brittle.

Wonder if Captain Tolly's Creeping Crack Cure would be better than
cyanacrylate? http://www.captaintolley.com/

Other possible methods:

Drill small hole at point of leak. Fit nut and bolt through hole with
and penny washers each side liberally smeared with a sealant.
Stainless or brass nut & bolt and washers though if well covered in
sealant ordinary plated steel parts might last reasonably well.

Use hot air gun and some extra plastic the same as the butt and try
to thermo-weld over the crack.

--
Cheers
Dave.