Procedure for when your Water Jetter Breaks Down

Q&A When trying to find the cause of a problem with a high pressure water jetter several questions must be answered before a correct diagnosis can be found. Fuel and water levels should be checked all the time and oil levels should be checked every 10 hours.

The Engine takes normal SAE 20-30 motor oil and the Gearbox/Pump takes 80-90 gear oil. (Always check the manufactures recommendation.)

COMMON PUMP PROBLEMS

Problem 1: There is no water coming from the jet hose.

Questions to ask operator

Is the water header tank full? (Low water cut off switch will prevent the engine from being started.)

Is the inlet valve to tank blocked? (Lizards live inside garden taps and can get jammed inside valve preventing full flow.)

Is the water pump inlet filter blocked? (Remove filter and clean.)

Are the jet nozzles blocked? (Clean with Mustang tip cleaner.)

Is the unloader valve jammed? (Should be replaced every 12-24 months depending on water hardness.)

Is the isolation valve working properly? (Check free movement in valve - on and off.)

(These can get stiff over time and not shut down the water correctly causing the unloader valve to play up.)

Is the hose kinked? (Unreel both hoses to examine for kinks.)

Problem 2: There is water coming from the jet hose but at low pressure.

Is the water pump inlet filter blocked? (Remove filter and clean.)

Has the machine been run dry for more than 30 seconds? (Pump may need new valves.)

(A dry pump causes the valve seats to heat up and pit/warp preventing the pressure from building up properly.)

Is the unloader valve jammed? (May have to be replaced - Take to pump specialist for valve inspection.)

Has the o'ring inside the quick coupler blown out? (Inspect and replace.)

Is the engine operating properly? (Go to common engine problems.)

If pump is still not operating after going through this check list above, take the jetter to your nearest pump specialist.

COMMON ENGINE PROBLEMS

Problem 1: The engine will not start.

Questions to ask the operator

Is the battery flat? (Check for loose leads. Pull start or jump start engine.)

(Make sure ignition key is left in the off position when not in use as this will drain the battery.)

Engine still won't turn over? (Check fuse located behind ignition key.)

Is the fuel tap turned on?

Is the fuel tank empty?

Is there water in the fuel? (Look into tank with torch to see water lying on the bottom of the tank.)

(Put a cup full of metho into the fuel next time tank is full and it will draw out the water over the next few hours or drain and replace with fresh fuel.)

Have you checked the engine to make sure there are no leads or plugs or wires hanging off?

Problem 2: The engine starts but stops again or runs rough.

Is the engine sitting level when running? (The engine has to be level or the low oil cut out switch will activate and shut down engine.)

Is there enough oil in the engine? (Check dip stick and refill. Do not overfill or cylinders will jam.)

Are both plugs firing? (Replace plugs. One dirty plug or a faulty coil will cause engine to run rough and drop water pressure by 50%.)

If pump is still not operating after going through this check list above, take the jetter to your nearest small engine specialist.