How to Clear Nail Gun Jams and Maintain a Roofing Nailer
Disconnect the air before you touch anything. Then open the nose, pull the bent nail, clean the channel and find out why it jammed.
- Intermediate
- 10 to 20 minutes
- Updated
The short answer
To clear a roofing nailer jam, disconnect the air hose first, then open the nose or magazine latch, remove the bent nail and any debris with pliers, check the driver blade and feed channel, and reassemble. Prevent repeat jams by using the right nails, keeping the tool clean and lightly oiled, checking o-rings, and setting correct air pressure.
Every roofing nailer jams sooner or later. A nail bends in the nose, the driver blade catches, or a collated strip feeds crooked, and the tool stops firing. The temptation on a busy roof is to pull the nail out with the air on, bang the tool on the deck, or keep pulling the trigger. Those habits cause most nail gun injuries.
Clearing a jam is a simple job if you do it in the right order, and most repeat jams have a simple cause: the wrong nails, too little lubrication, a dirty feed channel, or a worn part. This guide covers the clearing procedure, the regular cleaning and oiling that stops most jams, and the signs that it is time to send the tool for service. For normal use, see how to use a roofing coil nailer, and for the air supply, how to set up an air compressor.
Tools
- Needle nose pliers
- Hex keys or the wrench supplied with the tool
- Small brush and clean rags
- Safety glasses
- Air tool oil
- O-ring kit matched to the model
Materials
- Replacement nails of the correct size and collation
- Replacement o-rings and driver blade if worn
- Degreaser safe for rubber seals
- Tool case
Safety first
- Always disconnect the air hose from the nailer before opening the nose, pulling a nail or making any adjustment. A nailer that is still connected can fire when the nose is pressed or the trigger is touched.
- Never put your fingers or face in front of the nose, and never try to clear a jam with the tool against your body.
- Wear safety glasses. Bent nails, springs and latches can fly out when the nose is opened.
- If a nailer fires twice on one pull, fires without the trigger or leaks air from the trigger valve, stop using it. It is damaged and dangerous.
Step by Step
Step 1: Stop, release the trigger and disconnect the air
Make disconnecting the air a reflex. Release the coupler and let the hose drop. Then fire the tool once, pointed at scrap wood, to release any residual air in the tool. If the tool is jammed it may not fire, but disconnecting the hose still removes the pressure source.
Set the tool down where it cannot fall off the roof, and do not work on it while balanced on a slope. Move to a flat spot or the ground if needed.
Watch out: Never clear a jam with the air connected, with the tool against your body, or with the tool pointed at anyone.
Step 2: Open the nose and the magazine
Most coil nailers have a quick-release latch on the nose. Others need a hex key to open them. Hold the tool steady with the nose pointed away, and open the latch slowly, because a spring may be under tension. Some tools have a safety contact that needs to be held back to open the nose. Follow the tool's manual.
Step 3: Remove the jammed nail and debris
Look straight into the channel, not at an angle. The bent nail is usually wedged between the driver blade and the nose. Pull it out in the direction it entered if you can. If the driver blade is stuck in the down position, do not force it. Push it back up with a screwdriver or a punch if the manual allows, with the air still disconnected.
Pick out pieces of wire, collation, and shingle granules. Even a small piece of grit can jam the tool again.
Step 4: Check the driver blade, nose and feed pawl
A bent or chipped driver blade causes repeated jams and needs replacing. A worn nose lets nails wander. The feed pawl advances each nail into place, and if it sticks or is weak the next nail will not line up. Clean the parts with a brush and a rag, and push the pawl by hand to check that the spring returns it.
Step 5: Reload, close the nose and test on scrap
Make sure the nails are straight, the coil is the correct angle, and the collation is undamaged. Discard any bent or rusty nails. Check the depth of the first few nails and adjust as needed, see how to use a roofing coil nailer. If the jam repeats immediately, stop and look for the cause.
Step 6: Find the cause so it does not happen again
Common causes include nails of the wrong size or angle, damaged or wet coils, air pressure that is too low, too little oil, holding the tool at an angle so the nail hits a knot or an edge, and firing into a nail already driven. Note what happened just before the jam, since it often shows the cause.
Step 7: Clean and oil the tool regularly
Shingle grit and sealant build up in the nose and magazine. A weekly wipe and brush keeps them clear. Put two or three drops of air tool oil in the air inlet, if the manual says the tool is oiled, then run the tool once or twice into scrap to spread it. Do not over-oil, which stains shingles. Do not use degreasers that swell rubber seals.
Drain the compressor and keep an inline water trap fitted, because water in the air line corrodes the tool from inside.
Step 8: Replace o-rings and worn parts, or send it for service
Air leaking from the exhaust or the trigger valve usually points to worn o-rings. O-ring kits are sold for each model, and replacement is a matter of following the exploded diagram in the manual. If you do not have the tools, a service centre can do it. A nailer that double fires, fires without a trigger pull or has a cracked housing should not be used until it has been repaired.
Common Jam Causes
- Wrong nail length or collation angle for the tool.
- Bent or wet nails, or a coil that was crushed in the truck.
- Air pressure too low to drive the nail fully.
- Dirty or dry tool that needs cleaning and oil.
- Nailing on an angle into a knot, an old nail or a joint in the deck.
- A worn driver blade, nose or feed pawl.
A Simple Maintenance Schedule
Daily: check the nails, disconnect and wipe, oil if needed. Weekly: clean the nose and magazine, check the screws and latches, test for air leaks. Monthly or when performance drops: check the o-rings, driver blade and pawl. Keep a spare o-ring kit and a few spare nose parts in the tool case. A tool that is kept clean and lubricated will run reliably for years.
Common Mistakes
- Clearing a jam with the air connected. This is the leading cause of nail gun injuries during maintenance.
- Hammering the tool on the deck to free a nail. It damages the tool and can fire it.
- Bending the nail back and forth with the driver still down, which damages the blade.
- Using the wrong nails or crushed and rusty coils.
- Over-oiling. Oil drips onto the shingles and stains them.
- Ignoring air leaks. A leaking tool loses power and will jam more.
When to Call a Professional
If the tool fires twice on one pull, fires without a trigger pull, leaks air from the trigger valve, or the driver blade sticks, send it to a service centre. These faults are safety issues and are not field repairs.
If you are not comfortable opening the nose and handling the parts, have someone experienced show you first. A mistake when clearing a jam is one of the most common ways roofers are injured by nailers.
Fraser Roofing does free roof inspections across the Fraser Valley, from Hope to Abbotsford. See our Roof Replacement service or the towns we cover.
How to Clear Nail Gun Jams and Maintain a Roofing Nailer: Questions
How do you clear a jam in a roofing nailer?
Disconnect the air hose first. Then open the nose latch or magazine, pull out the bent nail with needle nose pliers, clear any debris, check the driver blade and feed pawl, close the nose, reconnect the air and test on scrap. If the jam repeats straight away, look for a worn part or the wrong nails.
Why does my roofing nailer keep jamming?
The usual causes are nails of the wrong size or collation angle, bent or damp coils, air pressure too low, a dirty or dry tool, nailing at an angle into a knot or another nail, and a worn driver blade or nose. Check the nails and pressure first, then clean and oil the tool.
Do roofing nail guns need oil?
Many pneumatic nailers do, and a few drops of air tool oil in the air inlet each day keep the o-rings supple. Some models are oil-free and must not be oiled. Check the manual. Too much oil leaves stains on shingles, and the wrong oil can damage seals.
How do you replace o-rings on a nail gun?
Disconnect the air, remove the cap or housing screws as shown in the manual's exploded diagram, pull the old o-rings and lightly oil the new ones before fitting. Use an o-ring kit made for the model, reassemble in the same order and test on scrap. If you are not sure, a service centre can do it.
Is it safe to clear a nail gun jam yourself?
Yes, if you disconnect the air hose first, keep the tool pointed away from you and wear safety glasses. Most injuries happen when people try to clear a jam with air connected. If the tool fires twice, leaks from the trigger valve or the driver will not retract, stop and send it for service.
Related Guides
All Roofing Tools guides|The full How-To Library
This guide is general education. Always follow the product manufacturer's installation instructions, the BC Building Code and WorkSafeBC requirements, which take priority over anything written here.
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