Pressure Washer Gun Repair: Fix Leaks, Sticking Triggers, Low Pressure, and Broken Safety Locks

Safety First (Guns Fail Under High Pressure)

The gun is a high-pressure component. A failure here can spray water unexpectedly or produce a sharp jet from a tiny leak. Treat repairs seriously.

• Shut the washer off and squeeze the trigger to relieve pressure.
• Unplug electric units or shut off fuel/engine switch on gas units.
• Never point the gun at people or pets—even during testing.
• If the gun body is cracked, replace it (do not attempt to glue or patch).

Step 0: Confirm It’s the Gun (Not the Hose, Wand, or Pump)

Water can travel along fittings and make the gun look like the problem. Before you open anything:

• Leak at the hose ends or along the hose? Use: Repair Pressure Washer Hose
• Leak at the wand/lance or quick-connect near the tip? Use: Pressure Washer Wand Repair
• Leak at the pump/manifold area? Use: Leaking Water From Pump

If water is forming at the trigger area, swivel, quick-connect, or safety lock area, you’re in the right place.

Common Pressure Washer Gun Problems (Pick Your Symptom)

• Gun leaking at trigger (drips from the handle or trigger pin area)
• Gun leaking at the swivel (leaks where the hose connects and rotates)
• Trigger is stiff or sticking
• Low pressure at the gun (but pump seems to run normally)
• Gun won’t shut off fully (water still flows or pressure won’t build)
• Safety lock broken or doesn’t hold

Fast Diagnostic: Does the Problem Change With the Wand or Nozzle?

Before you disassemble anything, do a simple isolation test:

1. Remove the nozzle tip and test briefly (carefully) to see if behavior changes.
2. Swap wands/extensions if you have another.
3. Inspect quick-connects for O-ring damage.

If your washer pulses or surges only while spraying, use the hub guide: Pressure Washer Pulsating. If the washer shuts off when you pull the trigger, use: Shuts Off When Trigger Is Pulled. This article stays focused on the gun itself to keep your content unique.

Repair #1: Fix a Leak at the Swivel (Where the Hose Connects)

Many guns have a rotating swivel inlet. This is a common leak point because the swivel uses O-rings that wear over time. The leak will appear right at the hose connection and may drip down the handle.

Likely Causes

• Worn or flattened swivel O-rings
• Debris in the swivel seat
• Cracked inlet fitting

Fix Steps

1. Shut off, relieve pressure, disconnect hose.
2. Inspect the swivel area for damaged O-rings.
3. Clean the seat and reinstall.
4. Replace O-rings if flattened, cracked, or missing.

If the leak is actually from the hose end fitting, fix the hose instead: Repair Pressure Washer Hose.

Repair #2: Fix a Leak at the Trigger (Internal Valve or Seal)

A trigger leak usually shows up as water dripping from inside the handle near the trigger pin or spring area. This is often caused by a worn internal seal on the trigger valve.

What This Usually Means

• The internal trigger valve O-rings are worn
• Debris is preventing the valve from sealing
• The gun has internal corrosion (common after storage with water inside)

Repair Options

Some guns are designed to be serviced with rebuild kits (O-rings, springs, valve stem). Others are effectively “sealed” and not worth opening. Here’s the practical approach:

1. Check for a rebuild kit for your specific gun model (often printed on the handle).
2. If a kit is available, replace the valve seals/O-rings and clean the valve seat.
3. If no kit exists or the body is corroded/cracked, replacement is usually safer and faster.

Safety note: if you’re not comfortable disassembling a high-pressure gun, replacement is often the best choice and can be surprisingly affordable.

Repair #3: Fix a Sticking or Stiff Trigger

A trigger that’s hard to pull or sticks halfway is more than annoying—it can cause surging, cycling, and control problems because flow becomes inconsistent.

Common Causes

• Debris in the trigger valve
• Corrosion from water left inside the gun
• Damaged trigger spring
• Gun used with harsh chemicals that degrade seals

Fix Steps (Non-Destructive First)

1. Flush the gun with clean water (water supply on, washer off, trigger held open).
2. Inspect the quick-connect and wand connection for binding O-rings.
3. Check the safety lock—sometimes a damaged lock rubs and causes friction.
4. If still sticking, the internal valve may need service or the gun should be replaced.

If the trigger sticking causes an electric washer to cycle on/off while spraying, see: Electric Pressure Washer Surging. A sticky trigger valve can confuse auto-stop systems.

Repair #4: Low Pressure at the Gun (But Pump Seems OK)

If your pressure washer runs, but the spray at the gun is weak, the gun may be restricting flow or leaking internally. Before blaming the pump, run these checks:

Quick Checks

• Nozzle tip: a clogged tip is the #1 cause of “low pressure.” Clean or replace it.
• Wand blockage: debris can partially block the lance. Use: Wand Repair
• Gun valve not opening fully: sticking trigger valve can reduce flow.

If the unit pulses or surges while spraying, start with: Pressure Washer Pulsating. Low pressure + pulsation often indicates restrictions or air in the line, not a bad gun.

Repair #5: Gun Won’t Shut Off Fully (Pressure Won’t Build)

If water keeps flowing even when you release the trigger—or pressure won’t build—the trigger valve may not be sealing. That can prevent the pump from reaching normal operating pressure and can cause surging behavior.

Fix Path

1. Flush the gun thoroughly to remove debris.
2. Inspect the trigger mechanism for damage or misalignment.
3. If the valve still won’t seal, replace internal seals (if serviceable) or replace the gun.

If your washer surges at idle with the trigger released, the unloader/bypass system may also be reacting to the gun not sealing: Pressure Washer Surging at Idle.

When to Replace the Gun (The “Don’t Risk It” List)

Repair is great—until it isn’t. Replace the gun if:

• The body is cracked or visibly damaged
• The trigger pin area is worn and loose
• Corrosion is severe inside the handle
• Leaks persist after O-ring replacement
• No rebuild kit exists and parts are not serviceable

A new gun can prevent bigger problems, like uncontrolled pressure spikes or unloader hunting caused by erratic flow.

Prevent Future Gun Problems (Simple Habits That Work)

• Relieve pressure after use: shut off and squeeze trigger to release stored pressure.
• Don’t store it wet: drain water to reduce corrosion and sticking valves.
• Keep O-rings fresh: replace early when flattened.
• Avoid harsh chemical exposure: rinse after detergents.
• Don’t overtighten: most seals are O-rings, not thread-based.

FAQ

Why is my pressure washer gun leaking from the bottom?

If it’s leaking at the hose connection, it’s usually a swivel O-ring. If it’s leaking from the trigger area, internal valve seals are likely worn. Start by identifying the exact leak point with a dry-and-test method.

Can a bad gun cause surging or pulsing?

Yes. If the trigger valve sticks or doesn’t open smoothly, flow becomes unstable and can cause pulsation or cycling. Use: Pressure Washer Pulsating and Electric Surging for related symptoms.

Is it worth rebuilding a pressure washer gun?

If a rebuild kit exists and the body is in good shape, yes. If the gun is sealed, cracked, or heavily corroded, replacement is usually the safer, faster option.

What if my leak is actually from the wand or quick-connect tip?

That’s a wand/lance issue. Use: Pressure Washer Wand Repair.