Cat 3516 Seattle Low

  • Specs Summary
  • Power Range
    850-1000 mhp, 838-985 bhp, 625-735 bkW
  • Speed Range
    2300 rpm
  • Emissions
    EPA Tier 3, IMO II, EU Stage IIIA
  • Aspiration

Cat C12.9 High Performance Propulsion Engine

The C12.9 marine propulsion engine is ideal for high performance marine applications including yachts, fishing vessels, military vessels, governmental vessels and various other commercial high performance marine applications. The C12.9 is designed to be integrated with both the Cat Three60 Precision Control shaft line maneuvering and engine control solution as well as other marine industry throttle controls. The electronically-controlled C12.9 is offered in two power ratings: 850 mhp at 2300 rpm and 1000 mhp at 2300 rpm. Both ratings meet EPA Tier 3, IMO II, EU Recreational Craft Directive and EU Stage IIIA regulations. In addition to high power density, the C12.9 offers high torque at low engine speeds and fast acceleration throughout the entire engine speed range due to its air system design of integrated series turbochargers and a supercharger.


  • Power Range 850-1000 mhp, 838-985 bhp, 625-735 bkW


  • Speed Range 2300 rpm
  • Emissions EPA Tier 3, IMO II, EU Stage IIIA
  • Aspiration TA
  • Bore 5.31 in (135 mm)
  • Stroke 5.9 in (150 mm)
  • Displacement 787 in3 (12.9 L)
  • Rotation (from flywheel end) Counterclockwise
  • Configuration In-line 6, 4-Stroke-Cycle Diesel

Dimensions & Weights

  • Minimum Length 57.6 in (1463 mm)
  • Minimum Height 42.7 in (1085 mm)
  • Maximum Width 43.7 in (1110 mm)

Standard Equipment

Electronically controlled supercharger

Series turbochargers with heat shield

Watercooled exhaust manifold

Dual aftercoolers

Closed crankcase ventilation system

Thermostats and housing

Gear-driven sea water pump with bronze impeller

Common rail fuel system

Plate-type heat exchanger

Engine oil cooler

Engine-mounted fuel cooler

Vibration damper and guard

Grid heater

Electric fuel priming pump

Seawater pump outlet pressure sensor

Water-in-fuel detection switch

Exhaust gas stack temperature sensor

Coolant level sensor

Optional Equipment


  • 24V 120 amp
  • 24V 160 amp
  • 12V 200 amp

Transmission gear oil cooler

Transmission sensor packages for on- or-off-vessel monitoring

Instrument panel – MECP I

Electric starting motor

  • 12V
  • 24V