I have had a Mash & Boil with a pump for about five years and for the last couple of years I have had a small, slow leak from the pump fitting into the vessel. I purchased o-rings recommended by Williams Brewing, pulled things apart, put them back together with an o-ring between the fitting and the exterior wall, which didn’t feel right, and now I have a larger, faster leak. I haven’t found a schematic for the Mash & Boil (series 2, not the 2.1), but if you own a M&B, can you advise, is this component supposed to come apart? And is there/should be an o-ring between the interior nut and the brew vessel wall? When I took it apart I didn’t see one. There is a barb fitting that goes into a silicon tubing that is locked down on the fitting with a metal “tie” (not sure what it’s called) and also a zip tie. I felt around and it was dry around the pump and interior fitting, suggesting I had reassembled it ok and pointing to the connection between the pump fitting and the exterior wall. Maybe the o-ring fell out?
I replaced an o-ring on the backnut of the ball valve that was truly gross, and I cleaned/soaked/flushed everything (including the ball valve) and scrubbed and rinsed out the interior with Bar Keeper’s Friend until it shone, so that’s something I guess. I can mash without the pump, but I’d like to fix this if I can. And then have the brew day I’ve been looking forward to for two months!
I find that if I have a stubborn leak at a fitting, using either silicone grease or RTV silicone sealant is fairly effective. The grease is also known as keg lube and is typically food-grade. The problem with the grease is that it might get displaced and resume leaking when there’s hot liquid involved. That’s when the silicone sealant might be better. RTV silicone sealant does give off acetic acid when its curing and it smells like vinegar for a day or so, but it is typically a food-grade product. Use the regular RTV product and not the high-temperature product since the regular product can handle boiling temperatures without problem.
Yes, the RTV silicone sealant is messy and there will be bits and pieces of silicone to clean up if you disassemble the fitting in the future, but the stuff does come off of most parts. Its just a minor pain, but it should fix your leak.
Thanks, Martin! I do have silicon sealant and have used it on a CO2 manifold in a spot where I just didn’t trust the fitting, with good results, so I’ll keep that in my back pocket. In this case I was leak checking what I thought was the “repair” (but probably created another problem, later reversed) when I realized that the leak was actually coming from the TOP of the pump tube. It was very subtle, as the water dripped in a tight line down the back of the tube, making it appear that the leak originated at the bottom. On further investigation, I found a small o-ring wedged in the tube, likely forced down a little bit more during each brew session when I inserted the removable pump piece that discharges into the mash / boil kettle. I pulled out the o-ring, which looked fine, and put it back where it belongs, and the leak stopped. I’m going to spend a little more time tightening other connectors and making sure everything is ship-shape before doing a final pre-brew leak check. I did wrap a little tape around the fitting I originally thought was the issue, just for peace of mind.
I haven’t found a schematic for the Mash & Boil (series 2, not the 2.1), but if you own a M&B, can you advise, is this component supposed to come apart? And is there/should be an o-ring between the interior nut and the brew vessel wall? When I took it apart I didn’t see one. There is a barb fitting that goes into a silicon tubing that is locked down on the fitting with a metal “tie” (not sure what it’s called) and also a zip tie. I felt around and it was dry around the pump and interior fitting, suggesting I had reassembled it ok and pointing to the connection between the pump fitting and the exterior wall. Maybe the o-ring fell out?