20 Most Recent Dewalt DPD3100 Gas Pressure Washer Questions & Answers

These are the two simplest causes:
crankcase overfill situation . . check oil level and adjust as needed.
air filter blockage causing the engine vacuum to draw from the crankcase breather and the engine oil with it.

Dewalt DPD3100... | Answered on Aug 24, 2014

Common problem across brands. When you spray water the drop in pressure triggers the motor to take the hose pressure ~ 30 psi and boost it to ~ 3000 psi. Water coats these parts with calcium (hard water) or other junk and water contains bacteria which causes slime and scale. Once that pressure switch / valve is sufficiently clogged it doesn't move smoothly so it can fluctuate between sending a yes / no signal about whether you are squeezing the trigger or not. This causes the pulsing.

EZ test: take the the tip off the wand, start the unit, squeeze trigger - should run continously with no problem. If it does for sure you need to watch a video on dissembling and cleaning the valve body. It is not hard but you must work carefully to avoid losing parts especially springs and take digital pictures to record the order for reassembly.

Dewalt DPD3100... | Answered on Jun 04, 2014

Quite often it means that your water supply is too small... not enough gallons / minute.

Dewalt DPD3100... | Answered on Jun 04, 2014

first things first, before replacing I would wrap this valve with teflon tape and then retighten and see if the leak stops, I checked the entire schematic and found no listing for a spring so this is part of a valve assembly of some type. It might be the unloader or the thermal valve so if there is any doubt about getting the right pressure on the cap I would replace the valve to ensure safety. the valves I saw are less than 25.00 so for the price I personally would replace. check the surrounding area for cracks also. Now as where to buy parts, you can go to Dewaltservicenet.com and download a parts breakdown of the pump assembly and also other areas for this washer. You can also buy the parts online from them. Let me know if you need more assistance

Dewalt DPD3100... | Answered on May 03, 2014

10 w 30 for engine

10 w 30 and specify for [PUMP OIL]



Dewalt DPD3100... | Answered on Feb 09, 2014

regular unleaded hop that helped you

Dewalt DPD3100... | Answered on Dec 21, 2012

see if it has a low oil shut off and the oil is just at the level

Dewalt DPD3100... | Answered on Aug 10, 2012

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