Burner won't shut down

SOURCE: burner will not fire

Dear muttandjeff,
I do not know if you machine is single or three phase. But whatever, one simple thing is to check that you have the right rotation. If the rotation is good, then fuel can be pumped. Now there must be a sensor that switches on with water flow. No water....no fire. If there is water passing, then the sensor is stuck and showing that there is no flow. The thermostat also opens a solinoid valve in most machines of this type. If solinoid valve is faulty....fuel will not come out. If this is a diesel boiler...check gap of electrodes and condotion of fuel nozzel. One last thing, is something I found in a machine of a friend of mine. I found everything correct....but then I found that the fuel was totaly mixed with water. So, that you have correct fuel, is also important.
fulltech.

SOURCE: Had the Northstar 3000 psi Pressure Washer for 2

It is easy to check if your hose and quick connects are supplying enough water to the pump. Your pressure washer gallon per minuite requirements are printed on the machine and also on the pressure tips in GPM. Your post indicates 2.5 gpm but check your documentation of GPM. Next remove the tip from the wand and connect your hose with current quick connects to the machine. Start engine and direct the pressure wand into a bucket for exactly one minute. Measure the amount of water in the bucket, it should be very close to stated gallons. Do the same test with tip installed and compare measurement. If pump is starving for water you will not get proper amount of water in the bucket and the water hose will collapse. Two to four gallons of water per minute is not very demanding and should be delivered even with very small opening. You can even just direct the hose into the bucket for one minute and check how much water your hose is capable of delivering. I believe that you will find no problem with water delivery to pump. I would certainly enlighten Northern with your findings and question their evaluation. When you start using your pressure washer again try using it at lowest pressure to get the job done. Lowering the pressure to about 75% of max will increase the life of the pump and engine. Good luck with you pump

SOURCE: Pressure Washer Pump and Engine Stops Suddenly

The pump might be binding against the motor, causing the pump to overheat and temporarilly "seize up" and shut the engine off.
After cooling down for a brief period (5~10 mins) the engine can usually be re-started, but the overheating problem will keep coming back.

This happens when the pump either wasn't seated against the engine properly during it's initial instalation, or the pump housing wasn't machined properly and the PTO shaft is trying to drive the pump at a slight angle = excessive friction = overheating.

Try this:
1) Loosen the bolts that mount the pump to the engine just enough so that the pump can be wiggled slightly.
2) With the engine power switch in the "OFF" position, slowly pull the recoil starter rope so that the engine / pump completes about two revolutions. This helps to align the pump surface with the engine.
3) Lightly snug the pump mounting bolts in a criss-cross pattern, then slowly pull the recoil starter rope again to ensure that the pump isn't binding.
4) Finish tightening the pump mounting bolts in the criss-cross pattern (approx. 21 foot pounds torque).

The entire process should take you roughly about 10 mins from start to finish.

If this doesn't remedy your problem, then try running the engine for 20 mins with the pump COMPLETELY removed so as to isolate the components.

SOURCE: my electric stea pressure washer wont ignite

There can be multiple problems with the burner.


Here is a link to a page for troubleshooting burners.

link

SOURCE: Northstar PW shuts off hot if washer is moved. Honda engine

Being petrol driven, it may have a mercury kill switch which puts a ground on the ignition circuit stopping the engine if you move it. Perhaps for safety in case you overturn the unit somehow.