Need to understand what’s wrong with your Subaru pressure washer? Then you’ve come to the right place. Below, you’ll discover troubleshooting tips for a variety of Subaru pressure washers. Next to each symptom, there’s an explanation of what you need to do to resolve the problem. Make sure you refer to the right table (for your model).
| TROUBLE | CAUSE | REMEDY |
|---|---|---|
| Knocking sound | Piston, cylinder or piston ring is worn excessively. | Replace the worn parts |
| Piston pin and piston pin hole are worn excessively. | Replace piston or piston pin | |
| Connecting rod small head is worn excessively. | Replace tie rod | |
| Bearing for crankshaft main shaft is worn. | Replace roller bearing | |
| Abnormal combustion | Engine is too hot | Better ventilation |
| Too much carbon deposit in combustion chamber | Clear away | |
| Improper gasoline brand or low gasoline quality | Replace with qualified gasoline | |
| Spark lacking | There is water in float chamber | Clean |
| improper spark plug electrodes clearance | Adjust | |
| Something wrong with ignition coil, and so on | Check and replace damaged parts |
| TROUBLE | CAUSE | REMEDY |
|---|---|---|
| Unable igniting | Fuel is finished | Refill fuel |
| Carburetor is clogged | Check fuel line and dredge | |
| Float is leaking | Repair | |
| Needle valve is sticked | Dismantle float chamber and clean or replace needle valve. | |
| Spark plug is punctured, or short-circuited by carbon deposit | Replace spark plug | |
| Side electrode of spark plug is dropped out | Replace spark plug | |
| High-tension wire is dropped out | Weld on | |
| Ignition coil is punctured or short-circuited | Replace ignition coil | |
| Stop wire is located on engine body | Find out meeting and insulate | |
| Cylinder is seriously scored and valve dropped out | Repair or replace damaged parts | |
| Abnormal oil volume or inferior oil | Check the oil level and quality | |
| Exhaust pipe blocked up | Clean exhaust pipe | |
| Shroud leaking | Repair damaged part | |
| Cooling fins blocked by foreign matter | Clear cooling fins | |
| Gasoline engine overheat | Cooling fan is loosen and misfunctioned | Reinstall well |
| Connection rod deformation to make piston and cylinder bushing side wear | Replace connection rod | |
| Cylinder or piston or piston ring is worn | Replace the worn parts | |
| Improper adjustment of engine governor to cause high speed. | Readjust engine governor | |
| Crankshaft main bearing burnt out | Replace main bearing | |
| Beating sound | Piston, piston ring or cylinder is worn | Replace the worn part |
| Connection rod or piston pin and piston pin hole are worn | ||
| Crankshaft main neck is worn | Replace bearing | |
| Piston ring is broken | Replace piston ring | |
| Metal beating sound when abnormal combustion occurs | Too much carbon deposit in combusting chamber | Clear away carbon deposit |
| Too small electrode clearance of spark plug | Adjust electrode clearance properly | |
| Engine fuel is too much | Check relative parts such as carburetor | |
| The other | Improper fuel brand | Replace fuel |
| Engine is overheat | Find a cause and eliminate it | |
| Improper valve clearance | Readjust valve clearance properly | |
| Fly wheel is not connected with crankshaft tightly | Connect tightly |
| Problem | Solution |
|---|---|
| Is the engine running at full speed? | Move the throttle control to the FAST. |
| Is the low pressure nozzle connected to the wand? | Switch to a high pressure nozzle. |
| Is the water inlet or filter screen blocked, clogged or damaged? | Disconnect the garden hose from the water inlet; clean the water inlet and filter screen. If screen is damaged, remove damaged screen, insert new screen. |
| Is the high-pressure hose leaking? | Check the O-rings. If damaged, remove old O-ring with a small flathead screwdriver, and replace with new one. |
| Is the spray gun leaking? | Replace the pressure washer spray gun with a new one. |
| Could the nozzle orifice be obstructed? | Shut off the engine; purge air from the pump; remove the orifice from the adjustable nozzle or remove the spray tip from the nozzle extension; clean the orifice or spray tip using the wire tool from the maintenance kit. |
| Is the supply water temperature over 100° F? | Provide a cooler water supply. |
| Is the supply water pressure and flow rate adequate? | Test the supply water using a pressure/flow-rate gauge. If the supply water does not produce a minimum of 20 PSI and 4 GPM (25 PSI and 7 GPM for POWER flow+ models), look for an alternative source that can provide adequate pressure and flow. |
| Is the pump oil level low? | Add oil to the pressure washer pump. |
| Is the pump faulty? | With the high pressure hose removed from the pump, attach the garden hose and turn on water. Water will flow through the pump, now turn on the engine; the water flow should increase in pressure and length from where it exits the pump. If this does not happen there is an internal pump issue. If this does happen then there is likely a clog in one of the attachments; high pressure hose, gun, wand, or nozzle. |
| PROBLEM | CAUSE | SOLUTION |
|---|---|---|
| Engine fails to start | No fuel in tank | Fill tank |
| Water pressure in hose | Squeeze trigger to relieve water pressure Replace spark plug Replace spark plug | |
| Spark plug shorted or fouled | Replace lead wire or attach to spark plug Contact a qualified service center | |
| Spark plug is broken (cracked porcelain or electrodes broken) | ||
| Ignition lead wire shorted, broken, or disconnected from spark plug Ignition inoperative | ||
| Engine hard to start | Water in gasoline Weak spark at spark plug | Drain entire system and refill with fresh fuel Contact a qualified service center |
| Engine lacks power | Dirty air filter | Clean or replace air filter |
| Electric Start feature not working | Battery is not charged Battery wires disconnected | Charge the battery using the battery maintainer charger Connect the battery wires. |
| Detergent fails to mix with spray | Soap tank is empty | Add detergent to soap tank |
| High pressure nozzle attached | Use blue soap nozzle to apply detergent | |
| Pump doesn’t produce pressure | Low pressure nozzle installed Inadequate water supply Trigger handle or spray wand leaks | Replace with high pressure nozzle Provide adequate water flow Check connections and / or replace trigger handle or spray wand Clean nozzle |
| Nozzle is clogged Air in line | Pull trigger on trigger handle to remove air from line | |
| Hose is leaking Kink in hose | Replace hose | |
| Choke in START position Pump is faulty | Eliminate kinks in hose | |
| Push choke in to the RUN position. | ||
| Contact a qualified service center | ||
| Machine doesn’t reach high pressure | Diameter of garden hose is too small Water supply is restricted | Replace with 3/4 in. garden hose |
| Not enough inlet water Wrong nozzle is attached | Check garden hose for kinks, leaks, and blockages | |
| Open water source full force Attach the high pressure nozzle |