C280-12 Marine Engine Product Description Caterpillar

Product Description
1.1. Engine Service Life
2.1. Engine Specifications
3.1. Engine Design
4.2. C280-12 Engine
5.1. Drives and Gear Trains
6.2. Front Drives
7.2. Engine Front Gear Train
8.2. Engine Rear Gear Train
9.1. Reference Weights
10.1. Aftertreatment system description
11.2. Dosing Cabinet
12.2. DEF Tank
13.2. Mixing Tube
14.2. Reactor Housing
15.2. Selective Catalytic Reduction Substrate Block

C280 Series Engines are intended for use in these applications:

  • Petroleum

  • Marine

  • Marine Auxiliary

The engines are rated from 900 rpm to 1000 rpm.

Engine Service Life

Engine efficiency and maximum utilization of engine performance depend on the adherence to proper operation and maintenance recommendations. This adherence includes use of the recommended lubricants, fuels, and coolant/antifreezes.

For the engine maintenance that is required, see this Operation and Maintenance Manual, "Maintenance Interval Schedule" (Maintenance Section).

Engine Specifications

Table 1
C280-12 Marine Engine Specifications 
Operating RPM  900 to 1000 
Low idle RPM  300 to 500 
Cylinders and arrangement  50 degree v 12 
Bore  280 mm (11 inch) 
Stroke  300 mm (11.8 inch) 
Displacement per cylinder  18.7 L (1127 cubic inches) 
Total displacement  222 L (13530 cubic inch) 
Compression ration  12.5:1 
Aspiration  TA 
Rotation (flywheel end)  Standard rotation is counterclockwise.
Clockwise rotation is optional. 
Fuel Delivery  Electronic Unit Injectors 
Fuel  See this Operation and Maintenance Manual, "Refill Capacities and Recommendations" (Maintenance Section). 
Method of starting  Air starting motors 
Maximum allowable exhaust back pressure  254 mm (10 inch of H2O) 
Maximum allowable inlet air restriction  3.7 kPa (15 inches of H2O) 

Engine Design

C280-12 Engine

Illustration 1g00279793
C280-12 Engine design
(A) Exhaust valves
(B) Inlet valves
(C) Flywheel

Drives and Gear Trains

Front Drives

Illustration 2g02935577
Standard rotation
(A) Standard front drive
(B) Optional front drive
(1) Jacket water pump
(2) Aftercooler and oil cooler pump
(3) Auxiliary water pump
(4) Engine oil pump
(5) Optional scavenge oil pump
(6) Fuel transfer pump
(7) Scavenge oil pump

Table 2
Front Drives For C280 Series Engines 
Component  Speed (1) 
Jacket water pump  2522 
Aftercooler and oil cooler pump  2522 
Scavenge oil pump  1627 
Engine oil pump  1524 
Fuel transfer pump  1995 
Auxiliary water pump  2230 
Optional scavenge oil pump  1524 
(1) The speed of the component is listed for an engine that is operating at 1000 rpm. For an engine that is operating at 900 rpm, multiply the speed of the component by .9.

Illustration 3g02935580
(1) Water outlet
(2) Water inlet
(3) Oil outlet
(4) Oil inlet

Engine Front Gear Train

Illustration 4g00268306
C280 Series Engine front gear train
(1) Crankshaft
(2) Idler
(3) Idler
(4) Jacket water pump
(5) Aftercooler and oil cooler pump
(6) Scavenge oil pump or auxiliary pump
(7) Engine oil pump

Table 3
Front Gear Train For C280 Series Engines 
Gear  Number Of Teeth 
(1) Crankshaft  96 
(2) Idler  68 
(3) Idler  67 
(4) Jacket water pump  38 
(5) Aftercooler and oil cooler pump  38 
(6) Scavenge oil pump  59 
(7) Engine oil pump  63 

Engine Rear Gear Train

Illustration 5g00268312
(1) Crankshaft
(2) Large cluster idler
(3) Small cluster idler
(4) Camshaft
(5) Idler

Table 4
Rear Gear Train For C280 Series Engines 
Gear  Number Of Teeth 
(1) Crankshaft  81 
(2) Large Cluster Idler  90 
(3) Small Cluster Idler  45 
(4) Camshaft  81 
(5) Idler  81 

Reference Weights

Table 5
Approximate Engine Weights 
Dry weight of the engine with attachments  C280-12 Engine 
25140 kg (55300 lb)

Table 6
Approximate Weights Of Serviceable Parts 
Component  C280-12 Engine 
Cylinder block  6646 kg (14620 lb) 
Bearing cap   
Crankshaft  2091 kg (4600 lb) 
Flywheel assembly  486 kg (1071 lb) 
Crankshaft vibration damper  269 kg (588 lb) 
Cylinder head assembly  196 kg (433 lb) 
Cylinder liner  100 kg (221 lb) 
Piston assembly   
Piston pin   
Piston rod assembly   
Aftercooler core (1)  73 kg (161 lb) 
Unit injector   
Front housing   
Rear housing  456 kg (1003 lb) 
Used air cleaner element  29 kg (64 lb) 
(1) The weight is listed for a single-stage aftercooler. A two-stage aftercooler and an aftercooler with a deep core are also available.

Table 7
Approximate Weights Of Aftertreatment System Components for C280-12 Engine 
Aftertreatment Components  Weight 
SCR reactor housing (CEM)  2245 kg (4949 lb) 
Single catalyst assembly  21.5 kg (47.3 lb) 
Service/access door  24 kg (53 lb) 
Mixing pipe  153 kg (337 lb) 
DEF injector lance assembly  6.35 kg (14 lb) 
Dosing cabinet  90 kg (198 lb) 

Aftertreatment system description

Illustration 6g03498661
AVSpare supplied aftertreatment components are illustrated with dashed line rectangles.

Selective Catalyst Reduction (SCR) catalyst technology is used to reduce NOx emissions and particulate matter (PM).

The aftertreatment system is comprised of the following components:

  • Diesel Exhaust Fluid (DEF)

  • Dosing cabinet

  • Mixing tube

  • SCR reactor housing

  • SCR catalysts

Engine exhaust flows into the SCR System reactor housing through the exhaust inlet. Once sufficient temperature is achieved, the DEF is injected into the exhaust. Exhaust flows through a mixer assembly in the mixing tube to ensure that exhaust is stratified for uniformity. This mixing will ensure complete disbursement across SCR catalyst section. Precise DEF injection is monitored and controlled by an electronic controller in the dosing cabinet. The following components provide signals to the controller to control DEF injection for emission reduction:

  • Thermocouple located in the reactor housing.

  • Post NOx sensor

  • Pre NOx sensor is located in the mixing tube upstream of reactor housing.

DEF fluid is injected into the exhaust stream before entering the SCR. When injected into the exhaust stream, the DEF is atomized into droplets. The atomized droplets are then sent through the mixer. The mixer disrupts the exhaust flow and allows DEF to be distributed throughout the exhaust gas. Water evaporates due to the high temperature of the exhaust and releases ammonia (NH3) that was bound to the DEF. NH3 is free to react with the NOX and the oxygen present in the exhaust system stream. This reaction occurs on the SCR catalyst. NH3 and NOX are converted into gas particles of nitrogen and water.

Dosing Cabinet

The dosing control cabinet controls the following:

  • Rate of DEF flow to the injector

  • Compressed air pressure

The dosing cabinet houses the following:

  • Pump

  • ECM

  • Sensors

  • Manifold

  • DEF tank

  • Valves

Cat engine ECM and the aftertreatment ECM located in the dosing cabinet are designed to communicate with each other. This communication controls the complete engine/emission system in order to meet emission levels.

DEF Tank

A DEF low-level sensor is located in the main DEF tank. If the DEF level in the main tank drops below the low-level warning point, the sensor will warn the operator. The event will record on the engine ECM.

Mixing Tube

Pre NOx sensor is located in the mixing tube. The sensor communicates values by CAN bus module to the dosing cabinet controller for DEF management.

Reactor Housing

The reactor housing contains a NOx sensor located in the outlet piping. The sensor communicates values by CAN bus module to the dosing cabinet controller for DEF management.

Selective Catalytic Reduction Substrate Block

The Selective Catalytic Reduction (SCR) catalyst modules come in a four block configuration. The catalyst modules are stacked to create catalyst walls in the reactor.

The SCR catalyst modules are responsible for converting the NOx into N2 and H20. The decomposition and hydrolysis processes convert DEF into ammonia in the exhaust gas and at the catalyst face to convert the NOx into N2 and H20. The number of SCR catalyst units designed into the system directly relates to the total exhaust flow (kg/hr).