Can I use PTFE tape on a propane reg?

[Country Joe]

Hi there,

I got a new 47kg propane cylinder earlier today, and it leaks!
When you open the tap thing, you can feel a tiny puff of gas coming from where the reg screws in.

The big puff that you can feel only lasts a moment, but when I spray leak detector onto it, it bubbles.

I've tightened it up quite a bit too, on it's left-handed thread, but don't really want to over-tighten it, or strip the thread.

Can I just wrap PTFE tape round the reg threads, or is that as dodgy as using oil on an oxygen reg?

All the Best,
CJ

 

[Paul.]

The seal isnt in the threads, the brass bullnose is where the gas seal is made.
Have a look and see if its dented, sometimes you can polish out minor damage with scotchbrite, another trick that may work is to twist the reg a few degrees as you finally tighten the nut, to rub the mating faces together under the pressure of the nut.

 

[brightspark]

if the above doesnt cure it u can use gas spec ptfe tape on the bullnose joint . boc bottles used to be famous for having leaky taps and seals . i used to spit in the neck of bottle when i exchanged them see if they leaked also inspected the seal

 

[rikrobson]

If its the bottle's connector take it back or get another delivered.
If it's your reg just get a new one, they're not that expensive and it'll be cheaper than being blown up

 

[Hitch]

As Paul has already suggested, do it up finger tight, then rotate the regulator a few times back and forth then tighten up with the palm of your hand giving the spanner a smack or two. Never failed yet!

 

[Country Joe]

Hi there,
Thanks TIG Paul, brightpark, & rik.
The reg is quite new, only seen about 5 cylinders in it's life.
Began to think I wouldn't be able to get it off again! But I did.
I've rubbed it hard around the inside of the fitting, until my arm started to ache. It's even left a bit of a line around the bull nose part of the reg. The threads aren't looking so new now, either!
Anyway, I've graunched it up as tight as I dare, and it seems ok now.
Strange thing is, I used that leak detector spray when I first stuck the reg into the cylinder at about 3 o'clock this afternoon, and it seemed fine. Maybe I was being stingy with the spray!
Brightspark, I know what you mean about the leaky BOC cylinders. I used to use 20-30 oxy cylinders per week, some were leaky, and sometimes you'd get empty ones too, but with a new seal on.
I'll just be paranoid now, and give it a spray every time I use it - but that's not such a bad thing, at least for the duration of this particular cylinder, I suppose.
Thanks again guys,
All the Best,
CJ

 

[Country Joe]

As Paul has already suggested, do it up finger tight, then rotate the regulator a few times back and forth then tighten up with the palm of your hand giving the spanner a smack or two. Never failed yet!

Hi Hitch,
I think that's what made the seal, the rotating bit.
Might find I have to give it back with the space heater still attached, when it's empty. It was hard to get off last time, and now it must be twice as tight!
Ah well, not dead yet!
All the Best,
CJ

 

[mike os]

longer spanner needed then