3/16-32 Tri Cocks?

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DianneB
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3/16-32 Tri Cocks?

Post by DianneB »

My LE American uses 3/16-32 tri cocks that are in bad shape and I was looking for three new ones. 3/16-32 was a ME "standard" back in the day but can't find them now.

Has anybody seen 3/16-32 test cocks?
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cbrew
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Re: 3/16-32 Tri Cocks?

Post by cbrew »

sounds like a 10/32 screw should fit. any idea if that was a straight or a tapered thread?
If it is not live steam. its not worth it.
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DianneB
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Re: 3/16-32 Tri Cocks?

Post by DianneB »

cbrew wrote: Tue Mar 05, 2019 1:05 pm sounds like a 10/32 screw should fit. any idea if that was a straight or a tapered thread?
Can't tell but I think it is taper.

A 10-32 nut fits on the valve like a charm.
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cbrew
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Re: 3/16-32 Tri Cocks?

Post by cbrew »

see if you can run a screw into the boiler. if it is tapered, i would expect drag as it screws in.
this does not change the fact you can not find a tricock with this thread, but one could be made to fit.

Copper or steel boiler?
If it is not live steam. its not worth it.
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cbrew
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Re: 3/16-32 Tri Cocks?

Post by cbrew »

if copper, does the boss have enough surface to open up to a 1/4-40 mtp?
If it is not live steam. its not worth it.
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DianneB
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Re: 3/16-32 Tri Cocks?

Post by DianneB »

cbrew wrote: Tue Mar 05, 2019 1:20 pm if copper, does the boss have enough surface to open up to a 1/4-40 mtp?
No boss - threaded directly into the copper boiler sheet. I'd hate to open out the holes to 1/4-40
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cbrew
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Re: 3/16-32 Tri Cocks?

Post by cbrew »

yeah, i agree with that, so the only option i see is plug the holes, or make up close nipples that have 10/32 one end and 3/6 -40 on the other and use a off the shell globe valve.
do you use the tricocks?
If it is not live steam. its not worth it.
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DianneB
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Re: 3/16-32 Tri Cocks?

Post by DianneB »

cbrew wrote: Tue Mar 05, 2019 1:34 pmdo you use the tricocks?
Honestly? No, not even on full-sized :wink: I can't tell the difference between steam and water LOL!
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cbrew
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Re: 3/16-32 Tri Cocks?

Post by cbrew »

see that is my take on them also, so maybe just drill them out and make up a solid plug that will connect them to the back head
If it is not live steam. its not worth it.
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DianneB
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Re: 3/16-32 Tri Cocks?

Post by DianneB »

PROBLEM SOLVED!

I was able to free up two of the three tri cocks by soaking in vinegar for a few hours and carefully working the handles back and forth a little at a time and working some oil in until they had full travel back.

The third one would not budge! :( I boiled it in vinegar for a couple of hours and it slowly started to free up the same way and ended up fine.

I never tried boiling in vinegar before. I am surprised it was more effective than room temperature!

(Nothing pleases the Scottish side of me more than saving an original part rather than replacing it1 :mrgreen: 0
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NP317
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Re: 3/16-32 Tri Cocks?

Post by NP317 »

Now you understand why full-sized boiler rules specify annual servicing of those try cocks.
'Keeps them from seizing up.

I have functioning try cocks on my Ten Wheeler, but have never used them.
My Mikado has fake try cocks, Visual jewelry only.
~RN
daves1459
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Re: 3/16-32 Tri Cocks?

Post by daves1459 »

I've enjoyed reading your "conversation". I've always had trouble with tapered plug cocks seizing up. I've had them in injector water lines, sight glass drains, and boiler water try cocks. Last year I experimented with plumbers silicon grease. It is supposed to be good up to 500F and not wash out. I found it to work very well at keeping the cock plugs free. But, does wash out in steam applications and so has to be replaced once a season where steam flow is involved.

Dave
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