Leaky Mash Tun

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Apr 18, 2012
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Been homebrewing roughly 25 years. Usually brew extract due to time constraints. Decided to get back to all grain to spice things up. Figured I'd upgrade some pre-existing equipment. I've got an orange 10 gallon Igloo and purchased the Great Fermentations 10 Gallon False Bottom for Igloo Cooler kit (https://shop.greatfermentations.com...ooler-false-bottom-kit/homebrew-false-bottoms)

Of course it leaks.

Plan to silicone the hell out of it and Teflon tape it.

Any other suggestions to remedy?
Did that come with installation instructions? Can you take a good couple of pictures of the bulkhead installation?
Looking at the images on the page you linked, the order of the pieces shown on the bulkhead may not be correct.
I still have my 10 gallon Rubbermaid cooler (which I should sell or give away one of these days) and the bulkhead I used never leaked, but it was important to put the parts in the right order...

No installation instructions included. I followed a similar design assembly process I found on YT (brass fittings vs ss)


Ball valve on exterior and then o ring to washer to nut on interior. I tried an extra o ring on exterior with same leaky results.

Will post pics.

Thanks for the response day__trippr.
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Ok, the order that the video instructs would be correct, with the non-removable "nut" outside, then on the inside the O-ring, then washer, then locking nut.

But pinching the O-ring under a washer followed by the flat locknut is sub-optimal and likely the root cause of the leaking. My bulkhead has a locknut with a well carved into one side to nest a thicker silicone O-ring than what's shown in the pics, and without a washer in the middle, which helps that O-ring seal the threads, locknut and cooler liner.

You might see if you can find a thicker O-ring. That might turn the trick...

I'm a little confused with the way that thing is designed. I got a little chuckle out of how boastful the gent on the video was about how great the design was and how it won't leak. I think the assumption with the bulkhead as designed is that the unthreaded shoulder portion will insert into the cooler just far enough that the oring will crush up against it rather than just the threads. Maybe. But to be so proud of that bulkhead? Eh..
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I use a rectangular cooler for mash tun, and also ran into small leaks around the bulkhead.

I had already inserted a short piece of plastic conduit inside the hole to be able to tighten the bulkhead better, but there were still little drips at times.

Apparently the (large) rubber washer underneath the large stainless washer, on the inside, didn't make a 100% seal with the cooler wall. I resorted to using some RTV silicone to seal the inside. I think it has to do with the (inner) cooler surfaces not being regular (or smooth) enough.
If you end up using Silicone, I think you have to make sure it is food grade. When I was going to do mine that is what I was told. I ended up using a piece of 3/8 ID tubing that fit thru the hole of the cooler and did not leak. Added a simple nylon valve I found on Amazon and pulled the rubber out of a piece of water line I had laying around and used the metal wrapping as my screen. I got the idea from a user on another board, Denny Conn. It works great and cost me less than 50 bucks.
I hate these kinds of connections. If it were a pot, it'd go:

Non removable nut part of the bulkhead
cooler wall
washer (so that the next nut can tighten without scraping

The o-ring in this spot lets some liquid escape from the cooler but immediately be stopped form going anywhere else afterwards. Fingers crossed you dont' have a leak between the 2 walls of the cooler, the inner white and outer orange or yellow, or liquid will get in between those 2 layers.

The problem with the o-ring on the inside of it, is that while the o-ring will prevent leaks from outside of the o-ring, it won't prevent what comes through under it, closer tot he actual pipe, under the washer and such. Or the threads for the nut that goes next.

My solution was to open up the outer layer of the cooler, the colored portion, being sure that the inner white part stayed intact and untouched. Then the order described above. No more leaks. If your washer is oversized it can then lend some strength to the whole thing so you aren't relying on a flimsy thin wall.

Hope that made sense. Hard to describe. In the first picture, if your wall goes between the O-ring and washer, you won't have any external leaks. Good luck with leaks in between walls though. And assuming that funny ledge isn't so wide that the o-ring can't actually get compressed to start with.
Lol! Don't panic, worse comes to worst you use thread tape under Bobby's fancy lock nut...

It's true that putting teflon tape between the nipple and the locknut will stop the leak where the liquid spirals through the threads and under the oring. As long as the oring seals between the locknut and the cooler wall, AND there's tape packed in the threads, no leaks..
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