Crack in front water tan BAVARIA 44 2002

[amikeren]

Sub: Crack in front water tank

On our yacht-Bavaria 44 2002 we found a crack in the front water tank.

The crack is at the top of the right side.

Questions:

1. What type of plastic is the tank  made of?

2. Does anyone in the forum have an attempt to fix this  problem?

[Spirit of Mary]

The only way to repair the tank is welding with hot air and donor material. The Bavaria tanks are made of PE plastic. I reaired my watertank succesfully in this way.

[Yngmar]

Tanks are HDPE - this should also be moulded in them somewhere (top on ours). Get some HDPE welding rod and look up plastic welding. Practice a bit on milk bottles or something before you tackle the tank. It's not that difficult if you can get at it without removing the tank.

[amikeren]

Thank

[Salty]

Do you have any idea why the tank cracked in the first place ?

Does HDPE go brittle after a number of years ?
Was the tank stressed in some way, perhaps by over pressure, putting something very heavy on top, pounding in bad weather with the tank slack allowing the contents to slam against the top of the tank etc. Any thoughts on the matter could be useful for others to avoid this result.

[amikeren]

i have no any idea why the tank cracked in the first place

[Spirit of Mary]

The reason I needed to repair my watertank was not cracking for some reason, but my own fould. I thought I needed to take the watertank out. So I made a bigger opening in the bed floor with a jigsaw. I went too deep and cut into the tank, about 30 cm long and fully through the wall. The repair went well by welding and holds already 10 years now.

[Salty]

i have no any idea why the tank cracked in the first place

Thanks Amikeren, that’s something of a concern if the tank or the way it is installed, is not up to the job.

Also thanks Spirit of Mary, it’s reassuring to know that the tank can be “do it yourself” welded and that the weld has lasted well.

[Spirit of Mary]

When welding the HDPE tank you need a heat source with preferably controllable heat and concentrated so you can melt the tank material in the crack and add at the same time the melted donor HDPE material. Maybe you can rent a plastic welding heat source. I got one from my company.
Ger