John Guest Leak

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Budron

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Hey guys,

What's the trick with the John Guest tail piece fittings?
Tap-adaptor.JPG

Every time I connect up I have a leak.
I know that the hose has to be cut without burrs etc, but I just cant get it. Not small leaks either.
Any ideas on what i'm missing?

Cheers
 
Where's it leaking from?

If from the thread you may be missing the seal, if from where the line enters you may have a brocken leaf - look through the end & see if it all looks intact.
To fit, push in firmly & then give a gentle tug to set. Also make sure you are using the correct diameter line.

cheers Ross
 
Yeah using 8mm OD line. I need to put it in hot water to get it on so it's pretty snug.
It's leaking from where the line enters.
Are you able to get a decent cut with just a pair of scissors or do you need hose cutters?
 
wheres it leaking?

Ignore that just read your post

I've always used secatares (spelling?), like garden sheers. I think i read some where to use them...
 
Are you pushing the line all the way in to the point where you can't pull it back out again without pushing in the grey bit?

Are you using the right line?
 
Yeah using 8mm OD line. I need to put it in hot water to get it on so it's pretty snug.
It's leaking from where the line enters.
Are you able to get a decent cut with just a pair of scissors or do you need hose cutters?

Okay my line just slots right in, definitely no hot water needed.

I cut with scissors and just be careful to make sure it's reasonably straight and free of burs. Never had any issues.
 
Are you pushing the line all the way in to the point where you can't pull it back out again without pushing in the grey bit?

Yeah it doesnt come out when I pull it
 
As suggested, make sure it goes all the way in. It should feel like there are two "grabs" on the tube, one as it passes through the lock collet, and another as it passes through the o-ring. If you don't get the oring onto the line it will definitely leak.

BTW - checking that it won't pull out isn't enough, because the locking collet will close on the line even if the line hasn't passed through the o-ring...

Regards,

Andy
 
Could I also say from my point of view, cut your tubing with a sharp razor blade and make the cut as nice and straight as you can... Im sure this helps seal it better aswell in the fitting.... ;)

:icon_cheers: CB
 
Are you using the clear vinyl type line or the opaque type?

I had leaks with the clear type as it was too soft and deformed over time. When it gets cold it stop being flexible also and leaked every time it was bumped.

After switching to the opaque type (much harder/stiffer) the leaks stopped. :)
 
+1 for Shmick's advice - The line recommended by JG is stiffer and has a shiny white outer coating...
 
Stanley knife to cut your line.... That's what I use.
 
+1 for Shmick's advice - The line recommended by JG is stiffer and has a shiny white outer coating...

+2 ,other types will work temporarily.but you need JG for a long lasting seal.
 
you shouldnt have to heat the hose to get it to fit JG fittings, if you go to craft brewers website- beer line-select a 8mm hose then click "more" you will find a good description of how to fit hose to JG fitting-are you sure its 8mm hose not imperial,I coped this once when buying 8mm from a dodgy hbs
 
After much trying and many, many hose cuts, I think I've come to the conclusion that the hose must be the wrong size.
I got it from the local hardware place and am sure it was 6mm ID 8mm OD, but it definitely doesnt go into the JG fittings easily.
It worked fine on my old barbed fittings so who knows?

I guess i'll just buy more from craftbrewer, and that way i can get the 5mm ID line.

Thanks for all the replies guys

Cheers
 
Yeah using 8mm OD line. I need to put it in hot water to get it on so it's pretty snug.
It's leaking from where the line enters.
Are you able to get a decent cut with just a pair of scissors or do you need hose cutters?

If you are heating your hose then the O-ring seal will be deforming the tubing permanently which it should not do, it should just seal around the tube. What does the end of the tube look like when you release the fitting and pull it back out? if there is a definite ring where the O-ring was that is a good indicator that it has been deformed too much, if you have trouble getting the tube into the fitting try wetting the end of the tubing before you insert it.
 
Sounds like you have the issue sorted, however just have a good look at the dark grey inner clip of the fitting.
I had a cracked one in my system recently, leading to an undetected gas leak!
 
The Valpar Flexmaster II works a treat. I use it for everything. Now just need to find some nice black trunking for when it is used as a beer line in a portable set up.
 
I use Armacell to trunk my lines - just remember to talc up your lines before you try to feed them through (and two people makrs life significantly easier!)

Andy
 
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