20 Most Recent Dewalt DPD3100 Gas Pressure Washer Questions & Answers

Question edited for clarity, full 'make model (what it is)'. Question moved to a better category. This says you don't need it. You just need a 3/8 plug.145'F is the temperature it opens. https://mastertoolrepair.com/portable-gas-pressure-washer-parts-type1-dp3750-p-1687081.html There is one here, aftermarket type I guess https://cvindustrialhardware.com/shop/dewalt/valve-thermal-relief/ More here https://www.google.com/search?q=dp3750+thermal+relief+valve ..

See this diagram:
http://www.mastertoolrepair.com/images/DPD3100_pump.jpg?osCsid=1f3m03ijp5lcht6569kran6rk2

Remove Items 122 (Un;loader) and 138 (Thermail relief). Clean them up as best you can with a nylon brush under some slow running water. Dis-assemble the unloader valve completly to clean (both ends). Then lubrcate them with White Grease and reinstall both parts AFTER placing White grease in the cavity the valves mount into. Very briefly... Test water flow with the engine not running Then start the unit with water off and let run 30 seconds. Turn off engine. Turn ON water supply and test water flow engine OFF. Note you will get a certain amount of white grease initially that passes through the unit. Start unit and rapidly actuate the trigger 1/2 second on 1/2 second off multiple times to force the unloader valve to cycle.

You can get parts here if either of the valves have completly failed:
http://www.mastertoolrepair.com/dewalt-dpd3100-n001194-pump-p-59405.html

The above steps should get your presure washer working properly again.
Thanks for choosing FixYa,
Kelly

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.

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.

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

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

10 w 30 for engine

10 w 30 and specify for [PUMP OIL]

ANY AUTO STORE

THANKS AND PLEASE RATE JJ505

regular unleaded hop that helped you