The No-Leak MLT bulkhead design

I know silicone caulk won't adhere to the wall of the cooler, but it should serve as a custom gasket, right? In that it will conform to the contours/cracks/crevices available prior to curing. I was thinking of putting some around the nipple on either side of the inner cooler wall, then adding silicone washer on both sides, then ss washers behind those, locknut behind inner assembly, PVC behind exterior, then locknut and ball valve on outside. Should work well, right?

Bought two pack of small baby bottle nipples. Cut just after widest point. Placed this against inner cooler wall, followed by ss washer, locknut. PVC union between cooler walls, ss washer, ball valve. No leak so far with 3 gallons of water and some beer bottles for extra displacement. Also: triple wrapped threads, even though the locknut is probably bottomed out and the new "gasket/washer" is very tight on the nipple. From earlier leaks using o-ring, I feel the water was NOT travelling the threads, rather coming in from the sides. This new washer seems to easily solve that, and being food grade silicone that is normally boiled to sanitize, I know it can withstand the temps.

I was hoping somebody here could offer some advice. After fiddling with this design for a few hours I am pretty frustrated. The point of weakness for me in building this design appears to be between the locknut and the ball valve. Water travels down through the spigot, hits the closed ball valve and looks for somewhere to go. This is the only spot that does not have a oring on it. So it just seeps between the cracks and out over the lock nut. After a lot of testing I am fairly convinced the actual seal between the cooler walls is sound.

Has anybody else run into this?

My current configuration is as follows.

ball valve ------ lock nut -------oring -------cooler wall-------oring------igloo washer-----stainless washer-----barb

I am using this kit from Ritebrew.

Other than constantly reapplying teflon tape what can i do?

So you think water is leaking out of the back of the ball valve? If so, I'm not sure what else would fix that, other than teflon tape. Give the nipple 6-7 good layers of teflon tape before you screw anything onto it. That's always fixed whatever problems I've had.

I'm no plumber, though, so maybe someone else will have a better idea,

All you need is teflon tape on the threads under the locknut.

Just finished mine up. Great plans. I just modified it slightly due to some part availability and ended up with a fantastic seal using some grommets and O-rings. Thanks for the post.

Edit: Did my second all grain batch today. Efficiencies are right in the ballpark, so the braided SS hose is doing a bang-up job. I always hit it and beat it up a little stirring the mash and it is holding up just fine with no internal wire or other support.
Love the new system. Can't thank you enough for posting such a great conversion. Awesome.

JB

thanks so much. works great!

Thanks Bobby M, Im going to need this, building a mash tun soon.

Cheers :cross:

Hoping for some advice on widening the existing spigot hole in the cooler wall. I'm building this from a coleman xtreme 72qt cooler (so I can make 10 gallon batches of bigger beers and still have a reasonable water:grain ratio).

The cooler wall is exactly 1 inch thick. The existing hole with the spigot removed is 24.5 mm in diameter by my digital caliper. I'm going to need to widen the outside plastic wall to 1 1/8" (28.6 mm) to accommodate the nipple and PVC sleeve.

Since there's already a hole there, I don't know how I would center a spade bit or hole saw. Would I use a step bit for this? Or do you think I could get away with incrementally grinding away the outer wall plastic with a dremel tool until it is wide enough? How about the insulation - just do it rough and dirty with an Xacto knife?

Thanks for any tips!

Very coarse round file rasp, or An aggressive dremmel bit would work as well...I don't think a knife would cut it..

A step bit should work easily enough. It's what they're made to do, after all...

Cheers!

Thanks all for your help. I built my CPVC manifold today and ordered the bulkhead and fittings from bargainfittings.com. Once I have that pipe nipple I can find a piece of PVC to fit over it and know exactly what size hole to drill.. I'm going to go with the step bit. Excited to try it out on a big beer.

I just installed a modified version of this bulkhead fitting, (thanks Bobby M). I really liked the idea of the PVC ring to stabilize O-ring; but once I got the original Rubbermaid cooler valve out I realized how thin and non-parallel the spigot area is. I also didn't want to drill out the outer shell if I didn't have to.

My final fit-up put a second O-ring inside the cooler wall space, sandwiched between both the inner and outer ply's of the plastic. I used dash 315 O-rings that are a little thicker than the 314 rings. Because the O-rings are flexible I was able to persuade it into place with some gentle pushing and prying without over-sizing the outer hole.

I was also able to get away with only a single washer inside and out, possibly because of the extra thickness with the O-ring(s). But I did have to grind the OD profile of the outer washer to fit the outer spigot area. The molded orange plastic recess was interfering with it sitting flat.

I tested both boiling water and ice water for 24+ hours and have no leaks. Thanks for the input everyone!

The other trick, as an alternative to inserting a support ring, is to carve out some of the insulation and then pack the recessed area with two part epoxy putty.

Old thread but Bobby.. do you happen to have the pic still? Its not showing anymore

frettfreak said:

Old thread but Bobby.. do you happen to have the pic still? Its not showing anymore

Click to expand...

I found it archived elsewhere and re-uploaded it.

Resurrecting this thread because I need some advice for my new setup. I just got a Coleman 52 quart cooler and a ball valve cooler kit from bargain fittings http://www.bargainfittings.com/index.php?route=product/product&path=47&product_id=251

The nipple is threaded all the way and I got an extra silicone washer and locknut. I think I will get a cpvc spacer as well. Would the best way to seal this from the inside of the cooler to outside be locknut>silicone washer>inside wall>silicone washer>lock nut>cpvc to outside wall>washer>ball valve? I should I include the stock rubber gasket in there at all since it is stepped and goes inside the inside wall?
The way I'm thinking about trying it first is to reuse the stock gasket instead of a silicone one on the inside of the cooler since Coleman made it and from the factory it doesn't leak. The I'll slightly widen a silicone gasket to fit over the stock gasket part that goes inside the wall and use it on the outside of the inner wall and a cpvc spacer against it to apply pressure.
Thanks a lot for any help and insight

The critical elements to a bulkhead of this type is an interior gasket, AND wrapping the threads of the nipple with Teflon tape to prevent leaks at the threading b/w the nipple and the lock nut.

An exterior gasket should not be needed.