Replacing
Pistons/O-Rings
If you need to replace piston parts in your nailer, you can purchase a piston repair kit from Grizzly.
The Piston Repair Kit part number for Model H7943 is PH7943087. The Piston Repair Kit part number for Model H7944 is PH7944087.
Refer to the parts breakdown during this procedure to identify parts and their loca- tions inside the nailer.
Always disconnect the air supply from the nailer whenever servicing! During maintenance, a nailer con- nected to air may fire accidentally, causing serious personal injury!
To replace a piston and
1.DISCONNECT NAILER FROM THE AIR SUPPLY!
2.Remove all nails from the magazine.
3.Remove the four cap screws on the head of the nailer, near the exhaust port, and remove the cylinder cover.
4.The top of the piston should now be visible inside the cylinder, which is housed in the head of the nailer.
5.Watch the discharge area and push the top of the piston with your finger. You will see the piston shaft slide down the discharge area.
6.With a long flathead screwdriver or similarly shaped tool, push the piston shaft back inside the nailer until you can grip the piston head and remove it from the cylinder. (Be careful not to scratch the discharge area when push- ing the piston shaft with the screw- driver.)
7.Clean all parts with an automotive grade solvent. Make sure all ports are clear and blow the solvent away with compressed air.
8.Inspect for cracks and wear; replace any part that is worrn or shows heavy wear, then relubricate the tool.
9.Place a new
10.Insert the new piston in the cylinder. Make sure that the grooves on the piston shaft align with those on the guide at the bottom of the cylinder.
DO NOT force the piston into the cylinder! If the piston is not easily inserted,
11.Replace the rear cap assembly and tighten the 4 cap screws.
For more assistance with
H7943 /H7944 Framing Nailer
