Common Pressure-Washer Parts To Fix "Engine Will Not Idle"
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Common Pressure-Washer Parts To Fix "Engine Will Not Idle"

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If your engine sputters out soon after starting and will not idle, the carburetor may need adjusting or be clogged and in need of cleaning. The carburetor mixes fuel from the gas tank with air before injecting it into the combustion chamber. If there are any blockages in the carburetor (usually caused by stale gasoline being left to sit in the engine and carburetor for too long), the engine will not receive sufficient fuel. This can cause the engine to sputter out, especially when idling. Gasoline that is older than 30 days should not be used to run an engine. If gasoline has been left in the engine for longer than 30 days and this problem occurs, the gas tank should be drained and the carburetor should be removed and cleaned. If you adjust the carburetor and the engine still will not idle, it is likely that the carburetor will have to be cleaned thoroughly or replaced, depending on its condition. Most carburetors have screws on them that allow you to adjust the amount of fuel and air being delivered. EPA law now requires all carburetors to be adjusted by a trained professional.

Unloader Valve

The power washers’ unloader valve is the mechanism that diverts the flow of water in the pump system into a loop when the user lets go of the washers’ trigger. This valve allows water to remain under pressure while it is not flowing out of the nozzle, without the pressure building too high in the pump. The unloader valves’ design allows water to keep moving within the pump system, so that it can be sprayed readily with consistent pressure the next time the trigger is pulled. This is accomplished with a piston head inside of the unloader valve that shifts to divert the flow of water if a spike of pressure is detected within the pump system (the type of spike that is created when the user lets go of the trigger). If water pressure inside of the pump is allowed to become too high, it could explode. The stalling of an engine due to a bad unloader valve is caused by the pressure in the pump becoming greater than the engines power to rotate the pump. If your engine will not idle and is continuously stalling, a bad unloader valve may be the cause. The unloader valve is located on the top of the power washers pump system, and occasionally has a black handle on its top. If the piston inside of the unloader valve fails to shift to divert the flow of water when it is not coming out of the nozzle, pressure inside of the pump system will be allowed to build to the point where it is unsafe and the engine will stall. If you are experiencing this problem with your power washer, the unloader valve should be inspected and possibly replaced.

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