Thread sealant/plumber's dope on fittings

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#1: Post by smkymtns »

Whoohoo, first post! I bought a used Brasilia Portofino 1 gr. this summer and it had been poorly taken care of. I had pulled everything apart, cleaned and descaled it a while back but I am finally ready to start reassembling. Some of the fittings looked like they had used some sort of liquid thread sealant under the copper sealing ring. Would it have come from the factory that way or could the sealant be the result of sloppy repairs. I don't see why you would use two types of sealing techniques here. But if that is the preferred method, should I be looking for something special in a sealant?



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#2: Post by mhoy replying to smkymtns »

Brush out the old stuff with a stiff wire brush (way better than using a dental pick). Ensure you don't have any in the boiler or any of the lines during re-assembly or you'll be taking things apart again.

The copper washers should be replaced as they deform on each use. You may be lucky and find some in the parts department at a car repair place. If you can't find any, you may be able to re-anneal them. This isn't recommended, but it's what I ended up doing for my Elektra T1 Heat the washer(s) until cherry red and let cool. Press flat when cooled, smooth with emery paper, be careful as they are now very soft.

For the other threads I used a little bit of Teflon tape, with no tape on the very end part of the threads. That way no Teflon tape would end up inside the machine clogging it up anywhere. BTW: Don't over tighten the copper/brass fittings, you can tighten them more if required, but twisting one off will leave you in a world of hurt.

Tighten up fittings, cycle the boiler a couple of times checking for leaks. Repeat.
The heat/cold cycle can also show up problems and/or loosen up joints, so do this on a work bench a couple of times so that leaks don't run all over.


smkymtns (original poster)

#3: Post by smkymtns (original poster) »

Thanks Mark! Just want to confirm something. You are saying you wouldn't use any sealant, correct? That would be my inclination as well. I have all new copper sealing rings, o-rings, gaskets, etc. so I am ready to go.

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#4: Post by cannonfodder »

You should not need thread sealer. If the crush washers are good, everything will seal up when tightened. Most of the pipes will have little bullet ends and use BSP fittings. The bullet ends seat against the pipe ends and the BSP fittings seal against each other. The fittings are tapered and will seal up when tightened. Do not over tighten your fittings. The rule of thumb, finger tighten then give them a half turn more. If they leak give them another quarter of a turn.
Dave Stephens

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#5: Post by mhoy »

Pat: I think you are well on your way. Post pictures of your work as it will be of use to the next guy doing the same thing. You may even have things pointed out to you that are really useful! I didn't know the previous owner had removed the thermal safety switch on my Elektra. :evil: Thank goodness someone asked me about it and I put a new one in.



#6: Post by djmonkeyhater »

I've had to use pipe sealant/dope on the odd fitting. Usually, it is attached to something or shaped such that you can't rotate it less that 359 degrees to adjust the "tightness".

I find it can be easier to apply than the Teflon tape in some situations.