Nailer: Doesn't Sink Nails Deep Enough

The seals seal in the compressed air and stop it from leaking from the tool. If you hear air leaking from the top cap it could be a bad seal. (All models are different and not all have seals). Remove the top cap and remove the seal. Inspect the seal for wear and damage. Replace the seal if necessary. When installing the top cap, tighten the screws in an alternating pattern a little at a time to seat the gasket properly. Always replace the gasket as they are a one time use.

A weak spring can impact the operation of the nail gun by not sinking the nails in deep enough. To check the spring remove the top cover from the nail gun. Remove the cage and valve from the cap. Separate the inside portion of the valve from the outside portion. Remove the spring from the inner portion and install a new spring. Reassemble the 2 portions of the valve back together and reassemble back into the top cover with the cage. Reinstall to the body of the nail gun and tighten the bolts in an alternating pattern a little at a time to seat the gasket.

The O rings seal the gap between the cylinder with the housing. If the O rings are failing they will allow air to escape impacting the operation of the nailer. This can cause there not to be enough air pressure in the cylinder to driver the nail down deep enough. If you are going to replace an O ring it is a good idea to buy a rebuild kit and replace all the O rings all at the same time since you are taking the nail gun apart. This will save you time by having to fix it again in the near future and you can purchase an O ring kit that has everything you need.

Remove the top cap off of the nailer, the magazine from the nailer and then remove the bottom nose piece from the gun. Pull the cylinder out of the nail gun, you may have to tap on the body with a rubber mallet to free it up. Remove the piston/driver assembly out of the cylinder. Remove the metal ring that supports the cylinder in the gun. There are O rings around the outside of the cylinder, and the metal ring that supports the cylinder. Inspect the O rings for tears, rips, and signs of deterioration or anything else out of the ordinary that is impacting the operation of your nail gun.

Replace any damaged O rings (or all the O rings if you are rebuilding it) by removing them with a small screwdriver by prying under them and lifting up. Install the new O rings and apply a little grease to the O Ring. Remove the cage and valve from inside the head. Separate the inside portion of the valve from the outside portion by pulling them apart. (Some piston head valves are an all in one unit with O rings on the outside). There are O rings on the outside and one on the inside. Replace these O rings and apply a tiny amount of grease to the O ring. Replace the O ring on the nose piece. Do not apply grease to this O ring.

Reassemble the inside portion of the valve into the outside portion and reinstall into the head with the cage. Install the piston/driver assembly back into the cylinder. Install the nose piece back onto the housing and tighten the screws across from each other a little at a time to seat the gasket properly. You should always install new gaskets as they are a one time use. Slide the metal ring over the cylinder assembly. Make sure the piston is all the way down in the cylinder for easier installation into the housing. Install the cylinder assembly back into the housing. Make sure the driver is aligned properly to the opening in the housing and press the assembly into place. Install the top cap with a new gasket and tighten the bolts a little at a time going around to each one to seat the gasket properly.

Make sure your nail gun is lubricated regularly so all the moving parts are free and working correctly. Add a 2 to 3 drops into the air fitting then attach the air and pull the trigger a few times to get the oil all around the moving parts.

The bumper stops the piston from banging into the bottom part of the cylinder causing damage to it and helps return the piston/driver assembly to the top. A broken bumper can cause the nails from the nail gun not to sink deep enough. To inspect the bumper you will need to access it. Remove the top cap off of the nailer, the magazine from the nailer and then remove the bottom nose piece from the nail gun. Remove the cylinder from the nail gun, tap on the body with a rubber mallet to free it up. The cylinder will pop right out. Remove the piston/driver assembly out of the cylinder. Remove the bumper from the driver and install a new bumper. Reassemble the piston/driver assembly back into the cylinder. Install the cylinder back into the nail gun by pressing it into the housing. Install a new gasket then attach the nose piece and tighten the screws in an alternating pattern a little at a time to seat the gasket. Reinstall the magazine, and the top piece. Install a new gasket between the top piece and the body. Tighten the top piece as well in an alternating pattern a little at a time to seat the gasket.

A leaky piston ring will need to be replaced as it will allow air to escape. This will result in the nail not sinking down deep enough in the material. To replace the piston ring, remove the top cap from the nail gun. Push up on the driver to remove the piston out of the nail gun. The cylinder may come out with it. Separate the piston from the cylinder. Inspect the piston ring for wear and damage that will allow air to escape. Replace the piston ring by using a small screw driver to pry under and up then walk it off the piston. Apply a small amount of lube or Vaseline around the piston ring and the piston then walk the new piston ring on by hand. Reassemble the piston/driver assembly back into the cylinder and reinstall into the nail gun. Install a new gasket between the top cap and the housing and tighten the screws a little at a time in an alternating pattern to seat the gasket.

When you pull the trigger it releases air driving the piston and driver down on the nail. If the trigger is leaking air it will impact its performance on driving the nails down. They may not go in deep enough because of a loss of air pressure. (On some models it might be easier to make this repair by removing the magazine first). To replace the trigger remove the O ring on the side and drive the pin out. The trigger will come out. There are different ways the valve is installed on different models. Some are threaded into the housing and some are held in place by roll pins. Unthread the valve or remove the roll pins and pull the valve out. Replace with a new valve or replace the O rings on the valve and reinstall back into the housing. Reinstall the trigger switch by positioning it in place and inserting the pin and O ring. Reinstall the magazine if you removed it.

The driver in most nail guns is a one piece unit with a piston on top of it. The piston/driver assembly is placed inside a cylinder. When the trigger is pulled it releases air and pushes the piston/driver assembly down on the next nail in line and drives it in to the material. To examine the driver lift the quick release and examine the driver. On some models you will have to take apart the nail gun to examine. If the driver is damaged such as a broken tip or it is bent this will impact how far the nails will go in. To replace the piston/driver assembly remove the cap on top of the nail gun and remove the cylinder assembly. (On some models you can just remove the piston/driver assembly). Remove the driver from the cylinder. Remove the piston ring from the piston by using a small screw driver. Place the small screw driver under and pry up gently and walk the ring off. Install it onto the new piston if it did not come with a piston ring then add a small amount of lube or Vaseline to the piston ring and reinstall the piston/driver assembly into the cylinder. Install the cylinder assembly back into the air nailer and reinstall the cap