Stanley finsish nailer and air is leaking through the trigger as.

Air leaking from trigger when attempting to fire the gun is normal and should cause nailer to fire, however if the trigger pin is not depressed all the way in,the gun may not respond. Easy test. Remove the nails and remove the trigger. Connect the gun to air and quickly depress the valve pin all the way in with finger. If the gun fires, adjust the safety foot so that the trigger pin is depressed all the way in. If the gun still does not fire, then remove the head cap and pull out the headvalve. Apply plenty of white grease to orings and retest. If the gun fires, then replace the headvalve orings. When the headvalve orings are worn, air will leak from bulkhead chamber to the headvalve chamber causing the gun to not respond to the trigger. The addition of grease to worn orings will make them temporarily seal. Good luck

Most likely problem is the head valve orings not making perfect seal. Remove the head and pull out the headvalve piston. Apply plenty of white grease to orings and test fire. If gun fires, will need oring kit soon. Good luck

Most likely the orings or seals in the headvalve are not making perfect seal. Remove the head and pull out the headvalve. Apply plenty of white grease to orings and test again. If the gun fires, then will need oring kit soon, or just keep using plenty of grease. If the gun still does not fire, check that the safety foot is depressing the trigger valve all the way in. Good luck

Sounds like your gun needs servicing. normally strip, clean and usually fit new O rings to head valve assy, piston & usually sleeve.

Worn orings in the gun and the trigger valve will cause the gun to fire upon connecting the air. It is a good practice to remove the nails when you remove the airline until you can replace the trigger valve. I believe that you gun uses a TVA6 valve. It should be replaced when it begins to leak or if the trigger pin seems loose and rocks from side to side. Factory valve costs about 25 dollars and aftermarket sells for about 12 to 18 dollars. Good luck

Remove the nails and take off the trigger to expose the trigger valve (usually part # tva6). Connect air and spray soapy water on the valve to determine if the air is leaking from the center of the valve or around the outer edge between the body and valve. If leaking from the center, could be defective valve or debris under oring. Pop out the valve and examine internal parts for cut oring or defect. If leaking from between body, you could have cut orings installing the valve. Make sure that there are no rough edges in the body of the gun. Bump fire or single fire happens with the trigger type not the valve. Bump fire trigger is usually black metal and single fire trigger is light color plastic. Good luck

If the new trigger valve leaks air when you connect the air supply, most likely defective valve or air is leaking past outer trigger valve orings due to debris in the slot or new orings were cut when the valve was pushed in. If air leaks when you depress safety to fire gun then most likely problem is in the head valve or safety foot is not pushing the firing pin all the way in. Easy test, remove nails and remove the trigger to expose the firing pin. Connect air and very quickly depress the firing pin all the way in. If the gun fires, adjust the safety foot as needed. If the gun does not fire, remove the head and check headvalve orings for good snug fit against the cylinder within the head. The surface were orings make contact must be very smooth and not too deeply worn. If you notice fine scratches remove with fine sandpaper. Reinstall head using plenty of white grease on all the orings within the head and retest. Good luck

If no air is leaking from the gun, take out the nails, remove trigger by removing 3mm hex head bolt to expose the trigger pin. With air connected and side door open so that you can see the feeder, quickly depress the trigger pin with finger. Gun should fire. If gun does not fire (only makes air sound at trigger) dissconnect airline, remove head and lube headvalve with white grease and reinstall. Test again. If ok replace trigger. If still no joy, replace trigger valve with new factory or generic (part # TVA6). If gun fires but does not activate the feeder claw, remove two 6mm hex bolts from front of gun and split apart upper and lower body and check white oring (part # 149885) Good luck

Remove nails and remove trigger to expose trigger valve pin. Place nose of gun against rubber pad or old coiled up air hose to absorb impact of driver and with very quick and deliberate motion press in trigger pin. If gun fires, then problem is with safety foot not pushing trigger pin all the way in (or worn trigger). Make adjustment as needed or replace faulty parts. If gun still does not fire, then likely problem is with headvalve. If headvalve orings are leaking, gun will not fire. Test for leaking orings as follows. Remove head and remove headvalve, apply silicone paste lube (plenty) to all orings and where orings contact. Assemble and do test above. If gun fires then surface where orings contact is allowing air to leak(smooth with very fine sandpaper if scratched).

Your nailer uses a trigger valve (part # tva6 cost about $20) and is sold at www.bostitch.com or generic valves sold on ebay . If you have a source for orings, you could try to repair the valve. Remove the roll pin that holds the trigger to expose the tva6 valve. There are roll pin/pins that hold the valve in just above the valve in the body. Remove these pins and apply air pressure to gun to pop-out the valve. Use caution when you do this. Remove nails, lower pressure to gun and use glove or rag to catch valve because it could come out with force. With tva6 valve in hand remove two pins that hold valve together and remove inner plunger. The middle oring on plunger is cause of leak. Try using an oring about same size as the broken seat. It must fit pretty tight to work. If you had a small leak it could be that the firing pin orings fit too loose or just too worn. Use silicone lube or oring lube on the orings and the valve port. Good holidays.