B&J Big Mouth Rebuild Kit

SMichalczyk

I have 4 B&J Big Mouth main steam vents. They’ve been great, however last year I accidentally left my water feed valve slightly open on my single pipe steam system and this caused water to run up the mains and come out of the big mouths. I drained everything and things have been mostly fine. 

My issue is that the big mouths don’t seem to fully close any longer when hot and they allow steam to escape as pressure builds even slightly. 

A knowledgeable member of the forum suggested I post and see about getting some rebuild kits. 

Can anyone let me know where I can get them and how much they should cost me?

Thanks in advance for the help. 

ethicalpaul

Just disassembling and cleaning them might help you. The water shouldn't have destroyed anything, but if it carried some rust particles into the vents the seals might be fouled.

Are you sure this steam leaking behavior you are seeing is new? They might have been doing that before your flood.

SMichalczyk

ethicalpaul said:

Just disassembling and cleaning them might help you. The water shouldn't have destroyed anything, but if it carried some rust particles into the vents the seals might be fouled. Are you sure this steam leaking behavior you are seeing is new? They might have been doing that before your flood.

Thanks for the response. I’m pretty confident they were not allowing steam to escape prior to flooding them. 3 out of 4 are doing this post-flood. 

Any recommendations on how to clean them?

ethicalpaul

They can be disassembled IIRC and are not complex...give most of your attention to the sealing discs and their mating surfaces

dko

I googled B&J Big Mouth and then selected videos.

Not something you want to do at work

SMichalczyk

dko said:

I googled B&J Big Mouth and then selected videos. Not something you want to do at work

Hahaha, I’m dying!

SMichalczyk

ethicalpaul said:

They can be disassembled IIRC and are not complex...give most of your attention to thsealing discs and their mating surfaces

Thanks, I will give it a try!

Neild5

The o-ring seal inside the big mouth is a -909, I replaced them with McMaster Carr part # 1173N684 and it stopped the steam leakage.

SMichalczyk

Neild5 said:

The o-ring seal inside the big mouth is a -909, I replaced them with McMaster Carr part # 1173N684 and it stopped the steam leakage.

Following back up on this. I took this advice and replaced the o-ring seal with the exact part mentioned. Worked like a charm. No more steam leakage from the big mouths. Thanks very much for this!