Briggs & Stratton Gas pressure washer Parts — Browse All Models

What causes a Briggs & Stratton gas pressure washer to spray too hard

A failed unloader valve can cause high pressure at the nozzle. The unloader valve recirculates water to the pump inlet when the pump is running but the spray wand isn't in use. If the unloader valve sticks shut, outlet water pressure builds up until you trigger the spray wand or the pressure relief valve trips to release excess pressure. Replace the unloader valve if excessive pressure builds when the spray wand isn't in use.

Some pressure washers have a pressure regulator that limits the water pressure. A defective pressure regulator can cause high pressure at the nozzle. Replace the pressure regulator if it doesn't regulate outlet water pressure properly.

How to fix your Briggs & Stratton gas pressure washer when the engine loses power

The engine requires an adequate supply of clean air to run properly, so replace the air filter if it's dirty. The engine also needs clean, fresh gasoline, so replace the fuel in the gas tank if the fuel is older than 3 months. If the carburetor is gummed up, the engine loses power, so check the carburetor and rebuild it if necessary. Replace the carburetor if it's too dirty to clean.

If the engine starts and run fine for several minutes but then loses power, the unloader valve may have failed. A failed unloader valve won't recirculate water back to the pump inlet, so pump outlet pressure builds up, making it harder for the engine to run the pump. The engine bogs down when it struggles to run the pump.

Try this test to see if a bad unloader is causing the engine to lose power. Stop the engine and remove the nozzle from the tip of the wand. Start the engine and hold the wand trigger down so water flows freely out of the wand. If the engine continues to run smoothly instead of bogging down after several minutes, then you'll likely need to replace the unloader valve.