Table of Contents
O-ring kit + seal LB3500 + BB0059
All the O-rings in the tool, Plus the seal LB3500 Plus the top piston bumper BB0059 which stops the bolt in the center of the driver from damaging the upper valve assembly BA0103.
O-ring kit + seal LB3500 + BB0059 + Bumper BB0018
This kit includes everything above Plus the lower bumper BB0018, this bumper is located at the bottom of the cylinder directly below the driver, looking down inside your gun it looks like a donut. You must remove the driver to see it.
Firing Valve Washer LB3500
Located on the valve BA0103 located in the cap on top of the gun. These get brittle with age due to dry rot. When installed the beveled edge goes up towards the top of the gun. The seal is available from below.
Other parts available
Front nose springs, Senco part # BF0008 Lock Spring and BF0023 Upper Lock Spring, sold as a pair, they are used but in very good condition. These 2 spring latches hold the nose together.
New Driver Pin. This is the square rod the drives the nails. So far I only have one available, with no bolt or washer to go with it. Senco part # EB0171.
Lower Bumper BB0018. Brand New polyurethane bumper. Goes at the bottom of the cylinder below the piston and driver. Every time the gun fires, the driver goes down at full force and strikes this bumper. It’s what keeps the driver from bottoming out, the driver hits it and rebounds back to the top.
O-ring kit only, All the O-rings in the tool, No other parts or seals.
Installing LB3500 Video on Youtube
Installing LB3500
SNIV and SN70 Identification
SNIV on the left, and SN70 on the right. Both use the same nails and share all the parts and kits available on this page.
Senco SN4 Schematic Diagram Download
https://www.rebuild-kits.com/wp-content/uploads/SEN-SN4-NFD017.-7-99.pdf