New MK25 Leaking

[TightLines]

Was recently given a brand new mk25 / s600 (luck guy eh?) and setup the new rig with my old octo, spg, etc. Tested it a few days ago and everything was completely normal. Set out to dive the new rig yesterday and low and behold the 1st stage has a big leak (can't even pressurize reg set) where the yoke connection attaches to the first stage. Since it was tested it sat in my reg bag untouched for a few days before the problem started. No dropping, fiddling, nothing. The whole thing is absolutely bizarre.

Disappointing start to what's heralded as such a fantastic reg. Worst case I'll have to go back to the person who gave it to me and implicate them in this whole process since they bought it online (LP) but wanted to avoid getting them tied up in the whole thing.

I do know that it was purchased brand new from LP so that eliminates anything shady. Any ideas?

 

[TightLines]

I've attached a photo to illustrate where the air seems to be coming from.

 

[redacted]

This is going to be a job for your local tech. Thankfully, it should be an easy job. Two candidates are a loose yoke retainer or a defective o-ring between the retainer and the body. You might try turning the yoke retainer. If you can turn it, it will need to be correctly tightened (best done with a special socket).

 

[NAM001]

iS THAT NUT LIKE ASSY HOLDING THE YOLK on tight. I had 2 of them leaking from that. I did not have the proper wrench so i put a screw driver in side teh yolk and along side of the nut like assy and turned the yolk. it turned perhaps a 1/4 turn and no more leak for me.

 

[tstormdiver]

I have seen the yoke nut come loose causing a leak & even seen the internal O-ring fall out &/ or get distorted when screwing it into the regulator body causing it to become shredded & cause leaking. There is a special ratchet attachment you can use to tighten the nut or I have even used a 12" crescent wrench in a pinch.

 

[halocline]

If you're absolutely sure that the leak is not in fact coming from the tank valve o-ring, then you probably have to remove the yoke retainer, replace the o-ring that seals the retainer, and re-install. If it was holding pressure and then suddenly didn't, chances are that o-ring got pinched or extruded and pushed out of it's journal. Just tightening it might not do the job.

This is a very easy thing to fix that would take a competent tech less than 5 minutes. Hopefully you won't get any BS from the shop about working on a reg that you did not buy from them.

 

[Fishpie]

The others are almost certainly right that it's the yoke nut or tank o ring but it might just be worth checking the HP hose is tight as a leak from its o ring can seem like a leak from around the yoke nut.