WATERAX MARK-3 Watson Edition Fire Pump with Integrated Fuel Tank

The MK3-WW is purpose-built to deliver exceptional portability and endurance for wildland firefighting operations. Its integrated 1 US gal. (3.8 l.) fuel tank provides up to ~45 minutes of uninterrupted runtime at full throttle - 100% and ~65 minutes at 75% throttle, allowing crews to stay focused on suppression efforts instead of refueling.

When operations extend beyond the initial attack, a three-way fuel valve enables quick, seamless connection to an external fuel source-ensuring continuous power exactly where and when it’s needed. Designed for demanding field conditions, the MK3-WW combines rugged protection, lightweight mobility, and reliable performance to support both rapid deployment and sustained operations in remote terrain.

Flow Rate at Specified Pressure

• Maximum Pressure: 380 PSI (26.2 BAR)
• Maximum Flow: 100 US gals./min. (379 l./min.)
• Maximum Head: 877 ft. (267 m.)

Performance

• 80 US GPM (303 l./min.) @ 100 PSI (6.9 BAR)
• 70 US GPM (265 l./min.) @ 150 PSI (10.3 BAR)
• 40 US GPM (151 l./min.) @ 250 PSI (17.2 BAR)

Engine

• Model & Type: WATERAX W140, 2-cycle, air-cooled, Nikasil cylinder
• Maximum Power: 10.7 HP (8 kW) @ 8000 RPM
• Maximum Torque: 7.6 lbf-ft. (10 N-m.) @ 7050 RPM
• Starting System: Recoil starter with backup manual rope starter

Pump End

• Type: Detachable, 4-stage, Centrifugal Pump
• Intake: 2 in. Male NPSH
• Discharge: 1-1/2 in. Male NPSH

Weight

• Dry: 53.2 lbs. (24.1 kg.)
• Wet: 59.6 lbs. (27 kg.)

Other Specifications

• Frame: Wrap-around (Standard)
• Drive Unit: Direct Drive
• Thread Protector Suction: Suction - 2 in. NPSH (Standard)
• Thread Protector Discharge: Discharge - 1/4-Turn Forged w/ Cap (Standard)
• Fuel Connector: SAE 45 (Standard) & Mercury