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Caterpillar 3126B Marine Engine Propulsion Info


Caterpillar Engine 3126B
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Power produced at the flywheel will be within standard tolerances up to 50°C (122°F) combustion air temperature measured at the air cleaner inlet, and fuel temperature up to 52°C (125°F) measured at the fuel filter base. Power rated in accordance with NMMA procedure as crankshaft power. Reduce crankshaft power by 3% for propeller shaft power.

Performance data is calculated in accordance with tolerances and conditions stated in this specification sheet and is only intended for purposes of comparison with other manufacturers’ engines. Actual engine performance may vary according to the particular application of the engine and operating conditions beyond Caterpillar’s control.

Parts for 3126 Caterpillar Engines

Specifications



I-6, 4-Stroke-Cycle-Diesel

Emissions
IMO compliant
Displacement
7.2 L (442 cu. in.)
Bore
110 mm (4.33 in.)
Stroke
127 mm (5.0 in.)
Aspiration
Turbocharged-Aftercooled
Governor
Electronic
Engine Weight, Net Dry (approx)
822 kg (1812 lb)
Cooling System
39 L (10.3 U.S. gal)
Lube Oil System (refill)
25 L (6.6 U.S. gal)
Oil Change Interval
500 hr
Caterpillar DEO 10W30 or 15W40
 
Rotation (from flywheel end)
Counterclockwise

Standard Equipment



  • Air Inlet
    • Sea water aftercooler, 12-volt air inlet heater, air cleaner with fumes disposal (closed system)
  • Charging System
    • 12-volt 51 amp alternator
  • Cooling System
    • Gear-driven auxiliary sea water pump, belt-driven centrifugal jacket water pump, auxiliary sea water lines, expansion tank, transmission oil cooler, engine-mounted heat exchanger with removable tube bundle and replaceable copper-nickel tubes
  • Exhaust System
    • Watercooled exhaust manifold and turbocharger, fumes disposal routed to turbocharger inlet
  • Flywheel and Flywheel Housing
    • SAE No. 3 (126 teeth)
  • Fuel System
    • Fuel priming pump, fuel filter — RH or LH service
  • Lube System
    • Crankcase breather; oil filter; oil level gauge, oil filler, oil pan drain — RH or LH service; gear-driven engine oil pump
  • Mounting System
    • Front mount is not included (Do not use shipping mounts in permanent installation.)
  • Protection System
    • Electronic overspeed shutoff
  • Starting System
    • Rear-facing 12-volt electric starting motor
  • General
    • Vibration damper and guard, Caterpillar yellow paint, lifting eyes

Accessory Equipment



  • 12V 110 Amp Alternator
  • Coolant Level Sensor
  • Coolant Recovery Tank
  • Crankshaft Pulley
  • Cruise Kit
  • 12V/24V DC Converter
  • Dress-Up Kit
  • Dry Exhaust Elbow
  • Engine Monitoring System
  • Engine-to-Engine Wiring Harness
  • Engine Vision Display System
  • Flexible Fuel Lines
  • Front Engine Support
  • Front-Facing Electric Starting Motor
  • Fuel Cooler
  • Fuel Temperature Sensor
  • GPS Interface Module
  • Manual Sump Pump
  • Marine Power Display System
  • OEM Wiring Harness
  • Pilot House Instrument Panel
  • SAE No. 2 Flywheel and Flywheel Housing
  • Spare Parts Kit
  • Throttle Position Sensor
  • Transmission Alarm Contactor
  • Watercooled Exhaust Elbow
  • Vibration Isolators

Dimensions



 
mm.
in.
Overhall Length
1580.7
62.2
Length from front to rear face of block
1041.4
41.0
Length from rear face of block to back of flywheel housing
136.0
5.4
Overall Height
917.1
36.1
Height from crankshaft centerline to top of engine
629.3
24.8
Height from crankshaft centerline to bottom of oil pan
287.8
11.3
Overall Width
889.9
35.0
Width from crankshaft centerline to port side (left side)
389.1
15.3
Width from crankshaft centerline to starboard side (right side)
500.8
19.7
Customer mounting hole diameter**
27.5
1.1
Width from crankshaft centerline to side**
285.7
11.3
Length from rear face of block to front**
716.3
28.2

**With optional front engine support

Available Configurations for Various Applications



General Engine Performance Parameters

Power
±3%
Specific Fuel Consumption
±3%
Fuel Rate
±5%

Ratings are based on SAE J1228/ISO8665 standard conditions of 100 kPa (29.61 in. Hg), 25°C (77°F), and 30% relative humidity. These ratings also apply at ISO3046/1, DIN6271/3, and BS5514 conditions of 100 kPa (29.61 in. Hg), 27°C (81°F), and 60% relative humidity.

Fuel rates are based on fuel oil of 35° API [16°C (60°F)] gravity having an LHV of 42 780 kJ/kg (18,390 Btu/lb) when used at 29°C (85°F) and weighing 838.9 g/L (7.001 lb/U.S. gal).

Additional ratings may be available for specific customer requirements. Consult your Caterpillar representative for additional information.

A Rating - 186 bkW (250 bhp) 254 mhp @ 2400 rpm

Typical Application . . . For heavy-duty service in vessels such as freighters, tugboats, bottom drag twawlers, and deep river towboats where the engine is operated at rated load and speed up to 100% of the time without interruption or load cycling.

Typical Hours Per Year
5000 to 8000
Time at Rated Speed
Up to 100%
Load Factor
480 to 100%
Typical Time at Full Load
No limit

B Rating - 205 bkW (275 bhp) 279 mhp @ 2400 rpm

Typical Application . . . Vessels such as midwater trawlers, purse seiners, crew and supply boats, ferries, and towboats where locks, sandbars, and curves dictate frequent slowing, and engine load and speed are constant with some cycling.

Typical Hours Per Year
3000 to 5000
Time at Rated Speed
Up to 80%
Load Factor
40 to 80%
Typical Time at Full Load
10 out of 12 hours

C Rating - 235 bkW (315 bhp) 319 mhp @ 2400 rpm

Typical Application . . . Vessels such as ferries, harbor tugs, fishing boats moving at higher speeds out and back (e.g. lobster, crayfish, and tuna), offshore service boats, and displacement hull yachts and short trip coastal freighters where engine load and speed are cyclical.

Typical Hours Per Year
2000 to 4000
Time at Rated Speed
Up to 50%
Load Factor
20 to 80%
Typical Time at Full Load
6 out of 12 hours

D Rating - 276 bkW (370 bhp) 375 mhp @ 2400 rpm

  • % Load Factor: up to 50
  • % Time at Rated RPM: up to 16
  • Typical Time at Full Load: 2 hours out of 12
  • Typical Hour/Year: 1000 to 3000
  • Typical Applications: Planing hull vessels such as off- shore patrol boats, customs, police, and some fire boats. Also used for bow and stern thrusters.

Power at declared engine speed is in accordance with ISO8665. Caterpillar maintains ISO9000 approved engine test facilities to assure accurate calibration of test equipment. Electronically controlled engines are set at the factory at the advertised power corrected to standard ambient conditions. The published fuel consumption rates are in accordance with ISO3046-1.

Fuel rates are based on fuel oil of 35° API [16°C (60°F)] gravity having an LHV of 42 780 kJ/kg (18,390 Btu/lb) when used at 29°C (85°F) and weighing 838.9 g/L (7.001 lb/U.S. gal). Additional ratings may be available for specific customer requirements. Consult your Caterpillar representative for additional information.

E Rating - 313 bkW (420 bhp) 426 mhp @ 2800 rpm

Typical Application . . . Planing hull vessels such as pleasure craft, harbor patrol, harbor master, and some fishing and pilot boats.

Typical Hours Per Year
250 to 1000
Time at Rated Speed
Up to 8%
Load Factor
Up to 30%
Typical Time at Full Load
1/2 out of 6 hours
Rated Speed
2800rpm
Maximum Cruise Speed
2600rpm
Maximum Continuous Cruise Speed
2400rpm

E Rating - 336 bkW (450 bhp) 456 mhp @ 2800 rpm

Planing hull vessels such as pleasure craft, harbor patrol, harbor master, and some fishing and pilot boats.