________________________________________________________________________________

Caterpillar 3116TA Engine

The Caterpillar 3116TA (Turbocharged-Aftercooled) is a heavy-duty, inline 6-cylinder, 4-stroke diesel engine engineered for marine propulsion, medium-duty trucks, and industrial equipment. It is highly regarded for its rugged cast-iron block design, structural rigidity, and high power-to-weight ratio. Utilizing a purely mechanical overhead cam and governor configuration, it functions reliably without complex electronic controls, though it requires precise mechanical synchronization and tooling during field service adjustments.

The 3116TA incorporates a Mechanical Unit Injection (MUI) system that completely eliminates external high-pressure fuel lines. A mechanical fuel transfer pump draws fuel from the storage tank, routing it through a primary water separator, fuel filter element, and a specialized check valve/pressure relief assembly to achieve a standard operating gallery pressure of 15-20 psi. Low-pressure fuel enters fuel galleries cast directly into the cylinder head structure to supply individual unit injectors. Each unit injector combines the pumping mechanism and spray nozzle into a single assembly, driven mechanically by a specialized third lobe on the engine camshaft via a rocker arm assembly. Injection timing and metered fuel volume are controlled across all cylinders through a unified mechanical governor linked directly to individual injector control racks

The lubrication system operates via a wet-sump configuration utilizing a gear-driven oil pump. The oil pump draws lubricant from the engine oil pan through a suction screen and directs it through a water-cooled engine oil cooler block and a spin-on full-flow filtration element. Regulated oil channels supply the forged crankshaft main bearings, connecting rod journals, camshaft lobes, and overhead valvetrain components. Dedicated external lines deliver high-pressure oil supply and gravity-assisted return drainage directly to the turbocharger cartridge bearings.

The cooling architecture relies on forced liquid circulation driven by a gear-driven centrifugal water pump. Coolant flows through the internal water jackets surrounding the engine block cylinders and cylinder head to maintain stable thermal profiles. Depending on the application, heat dissipation occurs via an industrial radiator or a marine heat exchanger integration equipped with an auxiliary raw sea-water pump. System regulation is managed by a mechanical thermostat assembly that modulates flow between the bypass channel and the core heat exchanger based on operational temperatures.

General Technical Data

Engine Specifications

Engine Model ............... Caterpillar 3116TA
Engine Type ............... 4-cycle inline 6-cylinder turbocharged liquid-cooled diesel
Number of Cylinders ............... 6
Cylinder Arrangement ............... In-line
Engine Bore, in (mm) ............... 4.13 (105.0)
Engine Stroke, in (mm) ............... 5.00 (127.0)
Displacement, cu.in (L) ............... 402 (6.6)
Rated Engine Power (Industrial), hp (kW) ............... 140-215 (104-160)
Rated Engine Power (Marine), hp (kW) ............... 150-300 (112-224)
Rated Engine Speed, rpm ............... 2200-2600
Peak Torque ............... 700-950 Nm (516-701 lb-ft) at 1400-1600 rpm
Aspiration Type ............... Turbocharged and aftercooled
Operating Speed ............... 2000-2600 rpm
Idle Speed ............... 600-700 rpm
Compression Ratio ............... 16.0:1-17.0:1
Firing Order ............... 1-5-3-6-2-4
Crankshaft Type ............... Forged steel
Piston Type ............... Cast-aluminum alloy
Con Rod Type ............... Forged steel
Cylinder Block Type ............... Cast iron
Cylinder Head Type ............... Cast iron
Lubrication System ............... Full-pressure
Oil Pump Type ............... Gear-driven
Oil Filter Type ............... Full-flow, spin-on
Cooling System ............... Liquid-cooled
Water Pump Type ............... Belt-driven, centrifugal
Air Cleaner Type ............... Dry two-stage
Starting System ............... Electric Starter
Electrical System ............... 12V or 24V
Alternator Rating, Amps ............... 55-120

Fuel System

Fuel System ............... Mechanical Unit Injectors (MUI)
Fuel Pump Type ............... Gear-type, transfer
Governor Type ............... Mechanical
Injection Pressure, bar ............... 1000
Fuel Type ............... Diesel Fuel

Dimensions and Weight

Overall Length, in (mm) ............... 41-45 (1050-1150)
Overall Width, in (mm) ............... 31-35 (780-880)
Overall Height, in (mm) ............... 33.5-35.5 (850-900)
Dry Weight, lbs (kg) ............... 1500 (680)

Maintenance Data

Service Information

Thermostat begins opening ............... 82C (180F)
Thermostat fully open ............... 95C (203F)
Cooling system pressure ............... 70-90 kPa (10-13 psi)
Operating oil pressure ............... 300-450 kPa (44-65 psi)
Idle oil pressure ............... 100-150 kPa (15-22 psi)
Intake Valve Clearance, in (mm) ............... 0.015-0.017 (0.38-0.43)
Exhaust Valve Clearance, in (mm) ............... 0.025-0.027 (0.64-0.69)

Engine Oil and Coolant

Engine Oil Type .................. SAE 10W-30, 15W-40
API Service Classifications ......................... CF-4, CG-4, CI-4, or higher
Engine Oil Capacity, qts (L) .................. 27.3-35.7 (25.0-34.0)
Coolant Capacity, qts (L) ............... 29.4 (28.0)

Service Intervals

Change oil and filter ............... Every 250 hours
Replace fuel filters ............... Every 500 hours
Inspect air filter ............... Every 50 hours
Change coolant ............... Every 2 years
Valve-lash adjustment ............... Every 1000 hours
Injector inspection ............... Every 1000-1500 hours
Compression test ............... Every 2000 hours
Drain water separator ............... As required
Belt inspection ............... As required

Service Specifications

Cylinder Bore Inside Diameter, in (mm) ................ 4.1348-4.1364 (105.025-105.065)
Crankshaft Journal Outside Diameter, in (mm) ................ 3.4996-3.5004 (88.890-88.910)
Crank Pin Outside Diameter, in (mm) ................ 2.7555-2.7563 (69.990-70.010)
Crankshaft End Play, in (mm) ................ 0.0030-0.0100 (0.076-0.254)
Intake Valve Stem Outside Diameter, in (mm) ................ 0.3130-0.3138 (7.950-7.970)
Exhaust Valve Stem Outside Diameter, in (mm) ................ 0.3122-0.3130 (7.930-7.950)
Intake Valve Guide Inside Diameter (Installed), in (mm) ................ 0.3155-0.3167 (8.013-8.043)
Exhaust Valve Guide Inside Diameter (Installed), in (mm) ................ 0.3155-0.3167 (8.013-8.043)
Intake Valve Stem to Guide Clearance, in (mm) ................ 0.0017-0.0037 (0.043-0.093)
Exhaust Valve Stem to Guide Clearance, in (mm) ................ 0.0025-0.0045 (0.063-0.113)
Intake Valve Spring Free Length, in (mm) ................ 2.463 (62.56)
Exhaust Valve Spring Free Length, in (mm) ................ 2.463 (62.56)
Intake Cam Height, in (mm) ................ 2.6457 (67.200)
Exhaust Cam Height, in (mm) ................ 2.5694 (65.263)
Piston Pin Outside Diameter, in (mm) ................ 1.5746-1.5748 (39.995-40.000)
Piston Pin to Piston Bore Clearance, in (mm) ................ 0.0003-0.0011 (0.008-0.028)
Top Ring Side Clearance, in (mm) ................ 0.0031-0.0047 (0.080-0.120)
Second Ring Side Clearance, in (mm) ................ 0.0024-0.0040 (0.060-0.100)
Oil Ring Side Clearance, in (mm) ................ 0.0016-0.0032 (0.040-0.080)
Top Ring End Gap, in (mm) ................ 0.0157-0.0256 (0.400-0.650)
Second Ring End Gap, in (mm) ................ 0.0098-0.0197 (0.250-0.500)
Oil Ring End Gap, in (mm) ................ 0.0098-0.0197 (0.250-0.500)

Tightening Torque Specs

Cylinder Head Bolts ............... 170-190 Nm (125-140 lb-ft)
Main Bearing Bolts ............... 200-230 Nm (148-170 lb-ft)
Connecting Rod Bolts ............... 110-130 Nm (81-96 lb-ft)
Flywheel Bolts ............... 180-210 Nm (133-155 lb-ft)
Crankshaft Pulley Bolts ............... 350-400 Nm (258-295 lb-ft)
Oil Drain Plug ............... 40-55 Nm (30-41 lb-ft)
Injector Hold-Downs ............... 25-30 Nm (18-22 lb-ft)

________________________________________________________________________________________

• Caterpillar Engines Specs
  
• Cat 3064 Specs
  
• Cat 3064T Specs
  
• Cat 3066 Specs
  
• Cat 3114 Specs
  
• Cat 3116 Specs
  
• Cat 3116T Specs
  

________________________________________________________________________________

________________________________________________________________________________________

_______________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________

________________________________________________________________________________________