Ballast Tank Crack

[Josh22]

I had a eval done on my boat last week and my starboard ballast tank (hard tank) has a crack in it. Do you guys know of any repairs kits to fix it? I hate to pull it and replace with new tank. 

Edited October 19, 2023 by Josh22
Tried to add photos

[CaptainMorgan]

How big? Where/can you see and access it?  Before Iwent thru pain of pulling/replacing it I'd definitely try to plug the leak.

Anybody know the tank material so we can guide to the right goo?

[wdr]

Polypropylene is pretty much the industry standard. Unless it was stepped on and cracked, I am betting that the inlet hole might be cracked from a freeze. For anything other than a catastrophic blow out  I bet some good prep and 5200 would fix the problem. At least I would try that before I sunk $400 into a replacement. Looks be da_ned so long as it works.

[justgary]

You can buy HDPE welding rods.  Use a hot air pencil to heat the local area near the crack until it becomes translucent, then apply the rod along the crack.  It is a lot like gas welding where you hold a torch in one hand and the rod in the other.  I have done several items, including a gas tank from a riding mower (fill it mostly with water except for the cracked area).  Lightly sand the area first to make sure it is clean.

A small hot air orifice works best, but you might be able to neck down a regular heat gun.  I have done that by making a cone out of aluminum flashing and hooking it to the end of the heat gun.  The small end was about 1/4", and it worked OK.

[Murphys]

3 hours ago, justgary said:

You can buy HDPE welding rods.  Use a hot air pencil to heat the local area near the crack until it becomes translucent, then apply the rod along the crack.  It is a lot like gas welding where you hold a torch in one hand and the rod in the other.  I have done several items, including a gas tank from a riding mower (fill it mostly with water except for the cracked area).  Lightly sand the area first to make sure it is clean.

A small hot air orifice works best, but you might be able to neck down a regular heat gun.  I have done that by making a cone out of aluminum flashing and hooking it to the end of the heat gun.  The small end was about 1/4", and it worked OK.

I had no idea there was such a thing as HDPE welding rods. Wishing that I had known about them when I repaired our tanks in 2012.

I used epoxy glue to repair cracks on the tanks, and thankfully the repairs are still holding.