Bulkhead Leaking

[nicky1200]

So i think i have installed my bulkheads the wrong way i have the nut on the inside of the tank and then the black seal unde the nut on the inside and then the white seal on the out side of the tank. The black seal in side is bigger than the white seal. Im guessign the nut and black seal needs to be on the out side ? and the hwite seal on the in side ??
 
Here is a pic of the bulkhead

 
 
I think i put the bulkhead on the wrong way and that is why it leaked and now i just had to saw it off because it some how locked it self.

 

[DrRob]

Yeah, you want the nut on the outside, that way the weight of the water presses down on the bulkhead and improves the seal. Personally I bed them in with a bead of silicone rather than any rubber.

 

[nicky1200]

And what about the black and white seals ?? Im guessing it goes on how it is in the photo ? Just the nut on the outside instead of inside.

 

[Maehlice]

DrRob is correct in that the nut should go on the outside.  Tightening the nut causes friction on the gasket, which can damage it (such as crumpling).  Being on the outside also makes it easier to remove later, if/when necessary.
 
I've put them on every which way and have so far never experienced leakage.
 
Many bulkheads only include one gasket, which goes on the inside.  If there are two, put the softer one on the inside.  The harder one is a washer which protects the tank by absorbing friction during tightening and distributing the pressure more evenly on the tank wall.
 
if both gaskets are soft but of different sizes, I have no idea which goes where.  I'd put the larger one on the outside with the nut.
 
Remember that bulkheads are reverse-threaded.  If you forget and try to turn it left to loosen it (I do that all the time), you're actually tightening it and could either really get it stuck or just think you got it stuck.