Stapler losing air around trigger is this a o ring problem?

https://www.menards.com/main/tools/power-tools/pneumatic-tools/air-nailers-staplers/masterforce-reg-pneumatic-coil-roofing-nailer/2085011/p-1444421094008.htm

http://www.fixya.com/support/t12846029-mastercraft_framing_nailer


also need to know the specific model number of nailer

Check for jammed staple, you have to remove the screws that retain the head of the stapler. If air is leaking then there is a bad seal at the trigger.

you need to replace rubber o ring on the trigger shaft pretty easy fix o ring is real small to deal with but doable automotive part stores usuly have assorted size in trays you can take old one out match its size .

you need a new trigger assembly, there is a split o ring on the valve assembly.

must dissemble the trigger mechanism and replace the broken or worn o ring that directs the air to the firing chamber.

you need a new trigger valve assembly, there is an o ring that has split. Contact Bostitch for a replacement part.

Trigger Valve needs replacing. Part Number is FA205BA1. The valve comes with instructions, its a pretty easy fix. Any BBostitch dealer should be able to get you one.

your problem is you have blown a seal. On some of the cheap chinese guns, it might be a flat gasket instead of an o ring.

May need cleaned and lubed. Check for bad o-ring.

I would agree with rowdy that the make and model number are essential to getting the right parts - If you have that information, just find a dealer that supports your brand. That being said, air leaking out the trigger area is likely to be an O-Ring or Seal problem. Pneumatic staplers have O-rings and Seals that need to be replaced periodically. Most have rebuild kits available that contain all the O-Rings and Seals that need to be replaced. Many staplers have O-rings and/or Seals on or near the trigger shaft that can wear and allow air to leak out