Prevent threaded connectors from leaking

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#1: Post by movnmik »

As I'm taking about my Rocket R60V there have been several water path connections that have almost like an epoxy to stop leaks.

After a imperceptible leak causing the premature death of my motor I want to know if that is something I should be using as I make these connections. Has anyone used these and if so what was used? Did it help? My new motor arrives next Monday and want to be prepared when it arrives.



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#2: Post by BaristaBoy E61 »

The source of the leak(s) have to be traced and properly repaired or replaced. It might be something as simple as replacing a gasket or an "O" ring. If your machine is direct plumbed what is now an imperceptible leak might become a kitchen disaster should it get worse while unattended.

Direct plumbed machines should have Leak Detection with automatic cutoff as the cheapest form of kitchen disaster insurance. I speak from experience as my wife directed my attention from what was nothing to watching what almost became like watching a person hemorrhage. Fortunately ¼-turn cutoff valves were within arm's reach. Had we not been home it would have been an expensive insurance claim.
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#3: Post by Jeff »


Can you post a photo?

There are at least two common "straight" threaded connector styles and then tapers, all of which should be sealed differently.


#4: Post by JRising »

The semi-tranlucent thread sealant that Rocket uses between elbows and valves that hardens into that epoxy like substance can be cleaned off with a wire brush and replaced with any thread sealant, or even teflon tape.

Don't confuse thread sealant used on the threads that seal inside other threads with the grease used to lubricate the threaded nuts of compression fittings. You obviously don't need and shouldn't use thread sealant on a compression fitting, it doesn't seal at the threads and anything other than an assembly grease on the threaded nut will simply interfere with your ability to feel its resistance to torque when you tighten it.

An R60V has the pump motor under the steam boiler. The steam boiler has no fittings on the bottom, one elbow and the element on the side, and everything else going through the top. Can you see where the leak was coming from on yours? It should have left a trail of water-stain.

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#5: Post by civ »

Jeff wrote: Can you post a photo?
It is important to see what type of fitting your machine is using (in this case) to be able define if it is a compression fitting or a metal/metal fitting and advise accordingly.



movnmik (original poster)

#6: Post by movnmik (original poster) »

Thanks for all that replied. It's truly appreciated!

The source of the leak was the steam boiler heating element. I took most of the hydraulic circuit out and will need to reassemble. The thread sealer that was on elbow connecter made to the brew boiler were threaded and not compression. I cleaned off two connectors of that harden thread sealer.

So I can use any thread sealant that is water potable and can resist high temp. I think I have some of the white sealant with teflon bits. I believe that would work. I also have rectorseal No5 which is also temp limit of 400f. I probably should go with simple white teflon tape.

Thanks for the note of thread vs taper. the two connectors going to the brew head are compression as with most other connectors. Again, I believe the only two pure threaded connectors are the two angle fittings attached to the brew boiler.




#7: Post by OrganicOctane »

Rocket uses Loctite 542. Unless they changed it to something else. 8)

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#8: Post by Jeff »

There are connectors that look to be "ordinary" threaded, but rely on face-to-face contact. I don't remember the trade name. Using sealant on them is something of a hack. Cleanliness and flat mating surfaces are key with that style.

Some connectors with straight threads need a gasket. I have seen copper, PTFE, and even paper.

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#9: Post by civ »

Jeff wrote: ... connectors that look to be "ordinary" threaded, but rely on face-to-face contact.
... don't remember the trade name.
If the OP could bring himself to post a photo, we could actually see what we're talking about.
Otherwise we're all guessing.

That said, it is most probably a Serto connector which relies on metal to metal/face to face contact.
Jeff wrote: Using sealant on them ...
Is not needed.
At most, the proper lubrication of the threads so that proper torque can be applied.
Jeff wrote: Cleanliness and flat mating surfaces are key ...


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#10: Post by NicoNYC »

OrganicOctane wrote:Rocket uses Loctite 542. Unless they changed it to something else. 8)
Hopefully they use 565 or 567 which are safe for contact with food (although for the miniscule amount of water contact in the threads it's probably a moot point). I think those ones should be good to seal threads off a boiler.