Repair bottom bulkhead without draining tank

[Curt2199]

So I have a 2" bulkhead that is a plugged old closed loop so it's on the bottom of my 700g. It's developed a constant drip and I'm wondering what my options are for replacing it without draining the tank and causing a large cycle. Anyone have any ideas? I've thought about using job water weld to put a large diameter Pnc pipe over the bulkhead inside the tank and then pump the water out of the pipe leaving a dry bulkhead that I can remove and fish out of the pipe replacing it with a new one.

Whatever I do needs to be careful and planned because it's in a new finished basement.

 

[dave.m]

Are you saying the leak is in the plug that blocks up the bulkhead (core), or is it leaking around the outer edges of the bulkhead? If it is leaking around the outer edges of the bulkhead then replugging/refilling the core will do nothing to cure the leak.

Sorry. In either case I do not know of a way to fix this without draining the tank.

Dave.M

 

[Curt2199]

The leak is around the bulkhead threads, not the plug within it. I have some weld-on 16 and am thinking about picking up a pvc cap larger than the bulkhead and sealing it over the bulkhead with the weld-on. I'd think that would work for a while.

 

[dave.m]

If it is just the core that is leaking then, yes, that might work. If you can truly manage to clear the top of the bulkhead as you have described and can get the top of the plug dry, you could then try to seal around the top of the plug as well.

You can only give it a try before having to break down your tank as a last resort.

Dave.M

 

[Reefstarter2]

Try putting an 8 inch pic pipe with a rubber seal of some sort over the bulkhead fitting in the tank . Then remove the bulkhead and replace ? All I can think of