I don't see the benefit in pushing people away from burst disks, but when servicing if you don't know the last time it was changed, you should change it. If you change it to something else like the stainless disk, because you are comfortable with that choice, then good for you.
In the US I'd say don't even bother servicing if it's a hassle, just buy a new valve from a shop like Dive Gear Express who usually has some for $25, but I don't know about the metric threading. A new seat is probably $5-$10 then orings are pennies, but getting it done at a shop will probably double your cost and then you could buy the $25 special from DGE and have a nice new valve, use the old ones as paper weights.
You just need a flathead to take off the knob, then a wrench to take off the nut holding the guts in, then you can unscrew the seat all the way--with drained tanks of course, don't try with a full tank. I imagine you could take the seat to a hardware shop to compare to bolts to confirm thread size and pitch and use that to match it up, but there's no shame in taking it to a dive shop and asking them to service the valves now, and you can take over in later years. The seat does not need to be replaced often, most servicing is just replacing the oring that is on the spindle and it's probably a #10, and every hydro replacing burst disk (if it's not stainless steel) and the neck oring.
In the US I'd say don't even bother servicing if it's a hassle, just buy a new valve from a shop like Dive Gear Express who usually has some for $25, but I don't know about the metric threading. A new seat is probably $5-$10 then orings are pennies, but getting it done at a shop will probably double your cost and then you could buy the $25 special from DGE and have a nice new valve, use the old ones as paper weights.
You just need a flathead to take off the knob, then a wrench to take off the nut holding the guts in, then you can unscrew the seat all the way--with drained tanks of course, don't try with a full tank. I imagine you could take the seat to a hardware shop to compare to bolts to confirm thread size and pitch and use that to match it up, but there's no shame in taking it to a dive shop and asking them to service the valves now, and you can take over in later years. The seat does not need to be replaced often, most servicing is just replacing the oring that is on the spindle and it's probably a #10, and every hydro replacing burst disk (if it's not stainless steel) and the neck oring.
