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Comet EWD4042G – Fully Plumbed Pressure Washer Pump


Available for Purchase!

SKU: C-6311010020 Categories: ,


Comet EWD4042G – Fully Plumbed Pressure Washer Pump with External Unloader

Same in Performance to Simpson / AAA 90034 Pressure Washer Pump – 4200 PSI @ 4.0 GPM.

Comet EWD4042G pressure washer pump 4200 PSI @ 4 GPM triplex pump comes complete with Built-In Pressure Regulator & Easy Start Valve and Oil. Just mount the pump, attach a plumbing set, set the pressure and your ready to go! Also known as 6311.0100.20

Comes with 1/2 in. FPT Inlet & 3/8 in. MPT Outlet.

Manufacturer Specs:
1 in. Hollow Shaft with SAE J609B Flange.
15mm Piston
RPM: 3400
Max. GPM: 4
Max. PSI: 4200

Pump Features:

  • -K Model includes built in unloader
  • Efficient Stainless Steel Check Valves with removable plugs for easy inspection.
  • Valves with double O-Ring to reduce overpressure risks.
  • Solid ceramic plungers to be high corrosion and abrasion proof.
  • 1/2 in. FPT Inlet – 3/8 in. Outlet (see pump sections for M or F)
  • Direct Drive Mounting Flange
  • Stainless Steel hardened piston guides.
  • Wide Oil Viewer
  • Thermal Relief Valve
  • Unloader valve knob with anti-unscrewing device.
  • Oversized conical roller bearings ensure long durability.
  • High-strength brass pump manifold with integrated unloader valve & pre-arranged for:
    • Detergent Suction (Chemical Injector)
    • Pressure Gauge
    • Thermostat Valve
    • Pressure Booster


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Customer Questions & Answers

  1. Answered by the admin

    The Simpson 4240 should have a Honda GX390 engine. The Honda GX390 has a 1 inch engine shaft. This pump has a 1 inch hollow shaft which matches the engine so it will fit.

    Other popular options are a Comet ZWD pump (search for: ZWD4040G-SUB4)  or the General EZ4040 Pump (search for: EZ4040G-SUB2)

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Prop 65 Warning!

This product can expose you to chemicals which are known to the State of California to cause cancer.