20 Most Recent Dewalt Pressure Washer. 4200 PSI 4.0 GPM Pro Triplex Pump Gas Questions & Answers

If it's new i would take it back and ask them to check it out or even replace it if needed.

Just pull out the suspect plug and replace with same.

every time it gets corrupted with water , it will turn from golden/clear to gold/milky when its time to replace it an allways ck your oil level in pump and engine an refill if needed when adding gas to tank , its natural to be missing some each time as equipment gets older an older

Check the bottom of the gas tank for dirt/debris and the float bowl for the same, if it has a fuel filter check that also. Sometimes, if there is debris in any of these places it will settle down when the gas flow is stopped. Then, depending on how the machine is being used or moved around while it is running, the debris will slowly be pulled into the gas flow until it creats a blockage and starves the motor of fuel. When the motor dies the debris settles back down in the tank/float bowl and the motor will start again. Clean out anything in the tank and float bowl and replace the fuel filter if it has one.

would it be possible to unscrew the quick connect fitting SLOWLY until water starts to drip out of threads thus allowing the pressure to drop down slowly to the point of being able to release the hose coupler?

That would be your unloader valve used for gun control. Allows system to go into bypass mode while the gun trigger is not depressed. This is already preset by factory specs usually a good idea not to move it unless you have a gauge to recalibrate it.

Try disconnecting the oil level switch.

The after fire solenoid helps prevent backfire when the engine is turned off. You can operate the genset without the solenoid and likely it will shut off without issue.

You can easily test by removing the solenoid plunger or the tip of the plunger and reinstall the solenoid.

page 15 DeWalt DPD3800 Instruction Manual Nozzle Cleaning

There should be a mark on the dipstick min and max. Keep within the 2 marks.