Leaking inside the casing. No pressure from the

Bad wand, bad wand hose, or clog at wand hose connector.

thats exaclty what a unloader valve does it unloads the pump when the trigger on wand is not depressed , it should however reseat and close off when trigger is pressed giving full presure to wand tip

it sounds like a flow switch that is installed in the inlet of pump can get stuck at times if you have a soap nozzle select it usually more flow moves the flow switch try and clean the flow switch if possible.

The fitting for the trigger is cracked. It happened to mine because I did not make sure the wand and hose was drained before winter came. The water left in the wand expanded and cracked the trigger housing. The problem is that the trigger piece is easily replaceable, but it is not available. Alltrade makes you buy the complete wand.

Hello, W/D here.

Sounds like it may be air locked. Connect the hose to the washer. Connect the wand and hose to the washer. Open the supply water, and hold down the trigger on the spray wand. Be patient, this can take several minutes.
Now crank the washer.
Best regards, --W/D--

THIS POWER WASHERS ARE TRICKY, TO OPERATED YOU NEED TO OPEN THE WATER FAUCET CONECTED BY A HOSE TO THE POWER WASHER , OPEN THE TRIGGER AND THEN START THE POWER WASHER, OTHER WISE YOU WILL RUIN THE POWER WASHER PUMP.

May be it's ice-clogged?

Hello awcockerill:
This sounds like the bypass (unloader) valve is sticking. Here is a diagram of your machine's pump. On page 2.4 see part #1. The top of this assembly is a black plastic cover. Remove all of assembly # 1 carefully. Under that is part #8. This is the bypass valve. You need to pull this out, check that the o-rings are not bent, worn or damaged, then lube it good with a VERY VERY good waterproof grease. Re-assemble it and all should be well. The part numbers are on the diagram but where to get them depends on were you live. Karcher web site may give you a number to call. Good luck.

I am afraid that is how they work even electric ones wont start unless you squeeze the trigger ,once they are running you should be ablr to release the trigger , and then squeeze it again whilst running . if yours dies when you release the trgger while motor is running -----good chance you are working at too high pressure. but to start you have to release all the internal pressure

I have a similar problem and diagnosed it to be a problem with the gun. I spoke to a technician that services this pressure washer and he walked me through all the diagnostic steps. The pump is working because there is pressure being built up and the gun sort of works because you can get water out before the washer is started. The technician said that the mechanism inside the gun is either clogged or broken. I am going to Home Depot or Lowes to purchase a new gun and will try it tonight. Guns are only about $30-40. He said generic is fine as long as the thread matches and PSI is in range. Good luck!