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mod90 · Veteran Member

Are there any particular maintenance tips for PCP rifles, like for the bottle, bolt, barrel, or internal mechanics? I mean besides cleaning & oiling the outer surfaces?

twalter · Veteran Member

Ive been wondering the same thing. Ive also found conflicting information around the net on leaving a Maruarder charged over 2000PSI for extended periods of time. I dread the though of having to pump it up fresh each time...

mod90 · Veteran Member

I know what u mean. A particular concern to me is how to check the integrity of the tank and valve/hammer system, if it needs to be pressure tested or inspected after a certain amount of fills or years. Also how I to check for corrosion inside the tank? What about guidelines on tuning or repairing these types of rifles? I guess this might turn out to be a DIY hit or miss experience.

AirGunEric · Site Admin

PCP's are really a whole different ball of wax compared to other airguns.

The main issue, of course, is to keep petroleum lubes away from the internals- can ignite and be a major issue. That being said- would adding a bit of silicone oil to the fill probe assist in getting lubricant to the valve? Or, is a completely manual process of disassembling everything to lube with a silicone grease more appropriate?

As for tanks getting old/corroding- I think it is likely going to be the case where seals fail long before this occurs (unless there is an extremely high level of moisture in the air used to fill the reservoir/tank)- and when replacing seals, a visual check at the very least should be performed. A hydrotest could be done on a rifle reservoir much like a diving tank- but it strikes me that this would need to be set-up exclusively for the purpose (i.e. the connection point-fill probe/QD) and I have not heard of anyone doing this.

Interesting, in the respect that as PCP is a relatively recent concept for mass-distributed product- there is no long-term experience to judge these things. However, if we use Co2 guns from days gone by as examples- I can't think of too many Crosman 160s that burst open or such because the tube was weak. I suspect if anything, a tube would not "shatter" when being filled if it had structural issues, but would instead bend/flex and spring a leak in a thin spot- they are, after all, steel tubes, not aluminum.

SMP · Silver Status Member

As for the bottles/tanks they would need a pressure test every ten yrs. the standard test is called a "hydro test" whereby the pressure vessel is filled with water then pressured to 125% of the working pressure.

If the air cylinder is removable (as in a match gun or the hatsans) it would also need a pressure test every ten years and you would be required to show this if you showed up at a sanctioned match. The manufacturer of the cylinder would be able to tell you where and how to get the cylinder tested.

If the tube is permanently affixed to the gun it would become way more problematic. If it was for your own peace of mind then you could do the test yourself by pressurizing to 125% of the working pressure with the gun buried under piles of blankets.

I regularly store mine with partial pressure in the tube(whatever is left after I have shot it down to the minimum pressure. But I also shoot every day or every other day.

As for regular maintenance it's fairly basic. I would put a tiny amount of silicone grease on the breach/bolt seal and I burnish the moving parts with moly when I have the gun apart. Don't lubricate the valve or valve stem simply keep it clean.

moetsch123 · New Member

I own three PCP rifles:

Sam Yan Ind, Sumatra .22
Shin Sung Ind, Samyung Fire 202 9mm (two)

All three have failed to hold any pressure at all. PyramidAir says this is to be expected every several years. Seriously? I've asked if I can fix the problem and the representative basically said 'no, i would need to send the rifle in for repair.' These rifles are heavy and I imagine shipping to be quite expensive not to mention the cost of the repair.

That answer seems unacceptable as it makes long term ownership of these PCP rifles unsustainable for us less fortunate ($$$) folks.

Does anyone have any experience/advice?

SMP · Silver Status Member

Yes your valve stems seals need to be under some load to hold their form.

If they are not leaking out as fast as you put it in then fill the gun several times and shoot it down. This may re seat your seals

moetsch123 · New Member

Thank you for the suggestion. There may have been multiple solutions but one of my major problems for all 3 air rifles was at the fill port where they were leaking. It turns out I they all needed to be tightened significantly. How they got so loose, and on all three rifles, is puzzling.

Once I got some air in them I did as you suggested. Thanks.

I can't tell you how relieved I am to have NOT to have had to send them in for repair for the estimated $150 + (including shipping both ways)! EACH!!!

Relief. Very Happy

Matt