The SIMPSON ALH3425 (part 60768) is a commercial-grade cold-water gas pressure washer built for contractors who need 3600 PSI / 2.5 GPM cleaning power around the jobsite, with the easy-starting Honda GX200 engine, a true AAA industrial triplex pump and a corrosion-resistant aluminum frame. It is the SIMPSON ALH series sweet spot - enough power for concrete and equipment, light enough for one operator to load and reposition.
Best for
- Concrete cleaning - driveways, sidewalks, shop floors and parking decks (pair with a surface cleaner attachment for even faster coverage)
- Equipment, fleet and trailer washing where 3600 PSI cuts brake dust, salt and road film without going to a hot-water unit
- Graffiti, paint prep and masonry cleaning on commercial and industrial structures
- Pressure-washing service businesses needing a daily-use rig that lasts more than one season
Specifications
- Pressure: 3600 PSI
- Flow: 2.5 GPM (9000 cleaning units)
- Engine: Honda GX200 commercial OHV gas engine
- Pump: AAA industrial triplex plunger with PowerBoost, integrated unloader and thermal relief
- Frame: aircraft-grade aluminum extruded tube
- Hose: 35 ft MorFlex 5/16 in non-marring high pressure
- Wheels: 10 in pneumatic
- Dimensions: 21 in L x 24 in W x 34 in H, 78 lbs
- Included: professional gun (safety lock-out), 16 in steel wand, 5 quick-connect nozzles (0, 15, 25, 40, soap)
- 49-state CARB compliance
Frequently asked questions
Is 3600 PSI safe for concrete?
Yes. Concrete tolerates 2500 to 4000 PSI without etching when you keep the wand at a reasonable angle and distance. The 3600 PSI / 2.5 GPM combination is a standard sweet spot for tire marks, oil stains and embedded dirt on concrete slabs.
Can I use this on a wood deck?
Not at full power. Wood decking generally cleans at 500 to 1200 PSI. Use the 40-degree nozzle, hold the wand at least 18 inches off the wood, and consider stepping up to a low-pressure soft-wash setup for sensitive stains and sealers.
How does 3600 PSI / 2.5 GPM compare to lower-pressure units?
Cleaning power is PSI x GPM. At 9000 cleaning units, this rig outperforms most consumer 3000 PSI / 2.0 GPM units by roughly 50 percent. Combined with the Honda GX200 and AAA triplex pump, it is built for daily commercial use rather than weekend driveway work.
What is included in the box?
A 35-ft MorFlex hose, professional spray gun with safety lock-out, 16-inch steel wand, and five quick-connect nozzles - 0, 15, 25, 40 degree and soap - plus the pre-installed engine oil specified by SIMPSON.
Does it need a special outlet or fuel?
No - it runs on standard pump gasoline (per Honda GX200 spec) and connects to a standard garden hose for water supply. There is no electric cord because the engine drives the pump directly.
Discount Cleaning Products is an authorized SIMPSON Cleaning dealer with US-based customer service. Add a 16 in or 20 in surface cleaner to the cart to multiply your concrete cleaning speed.
