nv83a nailer

[smbvb]

will a broken piston bumber cause the piston to not retract or is it just the piston o-ring

[Tinkerdave]

Hi Smbvb,
If the bottom bumper is broken or fragmented you will need to remove the upper head valve assembly and cylinder from the housing and thoroughly clean it to get every bit of broken bumper out.If you don't,little pieces of the bumper will float around and clog the air port to the feed piston causing the tool to skip nails and/or the pieces will get jammed in the head valve and between the piston and cylinder causing the driver to drag and not retract all the way up.
When you shoot an air nail gun and the air exits out the exhaust it creates low pressure in the top of the cylinder causing the driver and piston to be sucked up to the top of the cylinder.if this is not happening then something is dragging or bleeding off low pressure to the top of the piston.
Clean it thoroughly replace your upper and lower o-rings and bumper and that should do the trick.Hope that helps.Good luck.
Tinker