Scubapro MK10 issue. Bad seat or something else?

[happy-diver]

Resolve is sweet, bloody brilliant

Here's the poor mans build it yourself scubapro tool kit

including a Mk10 hone

 

[tom-153]

That looks great man!

Yea, I decided not to mess with too much DIY stuff in terms of tools, so I bought everything. In the end I prolly just should've bought a deep6 set from DGX for not much more $ since I also had to rebuild the 2nd stages with S wing poppets, upgraded the hoses, got a swivel, IP gauge, etc. hahah.

 

[Ghost95]

Resolve is sweet, bloody brilliant

Here's the poor mans build it yourself scubapro tool kit

View attachment 531253

including a Mk10 hone

You're missing the pipe wrench and Hammer.

 

[happy-diver]

Yeah mate, now you've got the stuff and it's beautiful

Here's my wrench-combined hammer

Fourty years of chiseling tools from stone and then a few months ago this falls in my lap

Never bought a kit in my life and then this, came with instructions ha ha ha ha ha

Thanks again skip cox on Scubaboard, what a gent!

but you can't beat the boys on here with their replace the piston shaft oring wooden chopstick tool

 

[tom-153]

Speaking of that o-ring, I had a tough time getting it into its groove even with Herman’s tool. The opening is really small so the o-ring had to be squeezed and put it n sideways to even get it started and then when I pushed it down where the groove was, it was still all crooked and even got twisted up when I tried to set it the first couple of times. In the end i had to use the plastic pick to get it into a better position before fully setting it with the brass tool. It must be real fun with less conventional methods...

 

[happy-diver]

I don't put any lube until it's installed

Fold it and poke it into the groove with something pokey, knitting needles for me or chopstick, hold it in the groove from below with a straight pick, knitting needle and then poke the rest in from above with a square cut bamboo chopstick with grip, whilst rolling the oring into the groove still from below with the pick or knitting needle
then blow out any wood rubble before lubing

Sometimes it takes thirty seconds sometimes three minutes and sometimes I have to walk away

 

[herman]

With my tool, it works better if the oring is well lubed, otherwise the rubber does what rubber does. It grabs and rolls instead of slides in. The oring needs to be well lubed anyway so that is not an issue. It does take a little practice to get the feel for it.
On the subject of lube, if you do take the reg apart for shims and you haven't already, a thin coat of lube around the area you polished out would be a good idea. The head oring needs to be lubed and any above or below the sealing surface will help prevent corrosion of the bare brass. No need for globs of lube but a shinny coat will help prevent more damage.

 

[Couv]

What is the general consensus on service intervals for mk10s and g250s that see maybe 20-30 dives per year?

Congratulations on your overhaul.

If this is your personal set, my thinking is not to worry about servicing it for a few years unless something is starting to fall out of tolerance. Re lubrication, this goes against SP's current thinking (but then again polishing out the defects in the chamber does too.) For a compromised surface that requires more protection, such as you have in your MK10, I would go back to the days of yesteryear and use a quality silicone lubricant such as Dow Corning Molykote 111. It not only provides more protection, not necessary better lubrication, but certainly good enough; and it's also more tenacious. Additionally, Moly is substantially less expensive than PTFE grease.

If you think that you'll be opening your toy up in the next year or two (you know you will) consider packing the ambient chamber with said inexpensive grease for further protection.

@superstar shows how it's done here: