SPLIT WATER TANK

Aug 11, 2011
881
O'day 30 313 Georgetown MD
Hi guys, need some help. My Starboard side water tank seems to have developed a split in one of the two dips. Anyone out there have knowledge how to fix. My guess its a polyethylene tank, but I have no knowledge about how to tell. Sorry, didn't think to get any pictures. I know I'll have to empty the tank, sand and clean the areas, but I have no idea what sealant to use. Would like to make it a permanent fix. Any help is appreciated, thanks guys.
 
Jan 7, 2011
4,789
Oday 322 East Chicago, IN
What year is you O30 ? I have a 1988 O’Day 322.

I removed my water tanks, painted under them, added clean outs, and then only installed one (30 gal each).
I was surprised at how robust the appear. Not at all brittle.


There may be a way to “weld” the crack, but beyond my knowledge to advise you.

Hopefully someone with some plastics knowledge can provide some guidance.


Greg
 
Aug 17, 2013
818
Pearson P30 202 Ottawa/Gatineau
Look for a plastic welder near you, I just had mine done, he put 3 3x3 patches and only charged me 80$ cdn
 
Aug 11, 2011
881
O'day 30 313 Georgetown MD
I removed my water tanks,
Looking at your video, it seems to be the removal is straight forward. How ever my boat does not have a removable access panel to get to the tanks, one with lips around to then lay in the cover board. I believe the tanks are put in place before the inner liner is dropped in during build. To remove the tank I would need to cut away the gel coated fiber glass top. Maybe a project for next winter.
 
Jan 7, 2011
4,789
Oday 322 East Chicago, IN
Looking at your video, it seems to be the removal is straight forward. How ever my boat does not have a removable access panel to get to the tanks, one with lips around to then lay in the cover board. I believe the tanks are put in place before the inner liner is dropped in during build. To remove the tank I would need to cut away the gel coated fiber glass top. Maybe a project for next winter.
The tanks on my O’Day 322 are in the settees, so they are pretty easy to remove. There is one brace that has to be removed in the middle of each settee, but not too difficult.

Sounds like yours will be much more involved.

Is the split visible (could someone weld it in situ)?

If not, then it sounds like a good winter project.

Good luck,


Greg
 
Jan 11, 2014
11,440
Sabre 362 113 Fair Haven, NY
Look for a plastic welder near you, I just had mine done, he put 3 3x3 patches and only charged me 80$ cdn
This is the answer. For a small job like yours it won't be cost effective to have a plastic welder come out to the boat. Pull the tank and take it to plastic welder or fabricator. There are no glues or sealants that will stick to the plastic.

The process requires cleaning the area, heating it with a flame, and then melting new plastic in the flamed section.
 
Dec 2, 1997
8,729
- - LIttle Rock
Repair is definitely worth trying--and heat welding is the only thing that'll work, and then only if done by someone who's skilled in doing it. But it MAY make more sense to replace the tank...it depends on the tank's wall thickness 'cuz the same stresses--flexing, bulging-- that caused the split can do it again if the tank has only 1/4" walls that aren't fully supported on all sides and that's the usual OEM tank wall thickness.

--Peggie
 
Aug 11, 2011
881
O'day 30 313 Georgetown MD
After watching a few videos on how to fix my tank, I got the gumption to try. I also have created a back up plan, should my repair not hold.
1) I twitched welded with my soldering gun, the split. I added plastic by using zip ties, melting it in on top of my stitches.
2) After sanding and cleaning the area involved, I dropped a large amount of Caulk Sealant over everything. Now it may not look pretty, but as it cures, it will level out and become clear.
IMG_0775.jpeg



IMG_0778.jpeg


IMG_0779.jpeg



It will take a good week to cure. Then I will test my repair.

3) My back up plan is to cut away the dimple and use a 12x12 sheet of 1/4" lexan, some sikaflex and make a gasket, basically making an inspection window.
 
Jan 11, 2014
11,440
Sabre 362 113 Fair Haven, NY
The dimple is a baffle to slow the movement of a lot weight fore and aft in the tank.