Help seal return Bulkhead 26mm in a 45mm hole.....

[Dukereefnz]

Drilled the hole 45mm, a large ABS bulkhead fitting fits but I can not get a 90deg fitting behind the tank unless I put a hole in the wall so I have changed to a smaller bulk head fitting which is 26mm.
Everything fits ok except the hole is to big and the bulkhead will not seal as it is.

The inside rubber washer is the same size as the hole.
The outside nut is smaller than the hole.

What are my option here...

Make a larger rubber gasket for inside.
Make a glass insert for the hole ... phot shows a wooden trial piece to see if this could work.
Make a larger ridged wash out of acrylic the covers the outside hole
Use silicon on both sides of the rubber gasket and thread sealant.

Anyone have any ideas that could work?

Here is one though with the ABS bulkhead that fits the hole, push the elbow in to the bulk head and try and glue it... but its not a tight fit.
ABS to PVC glue is not to be used under pressure....

I like this option but the hole in the tank is miles to big... look ok from the outside and fits against the wall.

Look OK this side tooo but wait...how do I seal this?

Here is the problem...

 

[blaxsun]

Honestly, I like your first option the best (top image). You could always try a "small scale" version hooked up to your pump to see if it's a tight enough fit after you glue the 90° elbow to the bulkhead. Do you have this issue on both sides or just the one?

 

[N1tew0lf1212]

You could probably use an acrylic piece like a washer but seal it to the tank. Creating like a stepdown size on the back side. Use silicon bead on the face squish to tank not all the way flush but close allow to cure and then silicone bead around exterior 90 degree edge.

 

[Hypan]

I’m assuming you have already tried a street 90 instead of a regular 90 with the original bulkhead?

 

[Dukereefnz]

Yes both sides....
I like the idea of a patch that could work well.
Also a Street 90.... did not try that... thanks

 

[Nonya]

Cap the bulkhead. Drill a new hole the proper size.

 

[Lbrdsoxfan]

I like the street 90 idea with a low profile bulkhead.

 

[Dukereefnz]

Made from acrylic.... silicon in from the front inside the tank.
Great idea

Not redrilling... it will spoil the tank...

 

[Dukereefnz]

What about installing the bulkhead backwards?
Will it still seal with a rubber washer both sides?

Not the most sexy option but it maybe the best?

Easy to notice now but it will disappear when running

 

[N1tew0lf1212]

Possibly my only concern would be pressure from inside to outpushing on the exterior seat over time it could leak. Could you seal around exterior fitting? What about a custome acrylic spacer with a rubber seal almost like a 26mm id to 45mm od. You can order online from custom plumbing shops.

 

[Nonya]

Do you have the piece you drilled out? Put it back in place as fill the gap with Weldon 16 a little at a time.

 

[Nonya]

Why can't you pull the entire stand and tank out from the wall a bit?

 

[Hairyteeth]

Why can't you pull the entire stand and tank out from the wall a bit?

This is the best option imo

 

[Nonya]

This is the best option imo

Right?

 

[KStatefan]

What about installing the bulkhead backwards?
Will it still seal with a rubber washer both sides?

Not the most sexy option but it maybe the best?

Easy to notice now but it will disappear when running

Just one gasket on the flange side

 

[Dukereefnz]

Stand and Cabnet are all built…
The return was left until last…
Bit of an over site … so no can do on moving out the tank from the wall.

 

[Nonya]

Just one gasket on the flange side

Only the inner gasket is ever necessary.

 

[Hypan]

Yep, if installing reverse. Gasket on the flange side (either exterior or interior whichever way the bulkhead is installed.)
I worked with a guy who always put silicone in the gap between the threads and glass before he put the nuts on his bulkheads. He was super worried about leaks all the time.

 

[Dukereefnz]

Thanks sounds like a plan!