International D188 Specifications
| Engine Model: International Harvester D188 |
| Engine Type: 4-cycle inline 4-cylinder naturally aspirated liquid-cooled diesel |
| Total Displacement: 187.5 cu.in (3.07 L) |
| Rated Engine Power: 40-46 Hp (29-34 kW) at 2200 rpm |
| Fuel System Type: Indirect fuel injection |
____________________________________________________________________________________
The International Harvester D188 is a robust
four-cylinder, four-stroke diesel engine engineered for agricultural
utility and light industrial service. As a key powerplant in the
International Harvester compact tractor line, it delivers a reliable
balance of power and torque for its displacement class.
The engine features a wet-sleeve cylinder design, which provides
distinct advantages in serviceability and overhaul longevity. Its
indirect injection fuel system promotes smooth operation and manageable
combustion noise. Built for durability in varied working conditions, the
D188 established a reputation for steadfast performance in mid-sized
farm tractors, where dependable daily power was paramount.
Engine Type: In-line, four-cylinder, four-stroke, liquid-cooled diesel.
Combustion System: Indirect injection, utilizing a pre-combustion
chamber.
Aspiration: Naturally aspirated.
Firing Order: 1-3-4-2.
Rotation (viewed from flywheel): Counter-clockwise.
Displacement: 187.5 cubic inches (3.07 liters).
Bore: 3.69 inches (93.7 mm).
Stroke: 4.39 inches (111.5 mm).
Compression Ratio: 18.7 to 1.
Rated Power Output: In the International 504 tractor application, 46 Hp
at the power-take-off at 2200 rpm. Drawbar power is approximately 40 Hp.
Governed Speed Range: 900 to 2200 rpm.
Weight (dry): 720 lbs (327 kg).
The cylinder block is a high-strength gray iron casting of deep-skirt
design. A defining characteristic is its use of replaceable wet-type
cylinder liners. These precision-machined steel or iron liners are
inserted into the block and sealed at the top by a copper or composite
gasket and at the bottom by synthetic rubber O-rings. This wet-sleeve
construction allows for cylinder refurbishment through liner replacement
without requiring block reboring.
The crankshaft is supported by five main bearings with generous bearing
surface area. Main bearing caps are made from nodular iron and secured
with two vertical bolts per cap. The block integrates internal passages
for oil distribution and coolant flow around each liner.
The cylinder head is a single-piece cast iron component. It is machined
to accommodate the pre-combustion (swirl) chambers necessary for the
indirect injection system. The head employs a crossflow layout.
Valve Arrangement: Overhead valves (OHV), actuated by pushrods and
rocker arms.
Valves per Cylinder: Two (one intake, one exhaust).
Intake Valve Head Diameter: 1.625 inches (41.3 mm).
Exhaust Valve Head Diameter: 1.375 inches (34.9 mm).
Valve Seat Angle: 45 deg.
Valve Stem Diameter: 0.3125 inches (7.94 mm).
Valve Lash (cold): Intake 0.015 inches (0.38 mm), Exhaust 0.017 inches
(0.43 mm).
Adjustment must be performed with the engine cold.
The fuel system is an indirect injection design utilizing in-line
injection pumps.
Injection Pump: An International Harvester/Bosch or CAV in-line jerk
pump.
This is a piston-plunger type pump with individual pumping elements for
each cylinder, governed mechanically.
Injection Nozzles: Pintle-type nozzles designed for pre-combustion
chamber use.
Injection Pressure: 1065 to 1140 psi (73.5 to 78.5 bar).
Fuel Lift Pump: A camshaft-driven, diaphragm-type mechanical transfer
pump.
Fuel Filter: A dual-stage filtration system with a primary sediment bowl
and a secondary spin-on or cartridge-type paper element filter.
Static Injection Timing: Requires precise setting as specified for the
model.
Common setting range is 22 to 24 deg before top dead center.
Timing marks are provided on the flywheel and injection pump drive gear.
The lubrication system is a full-pressure, full-flow design with a
gear-type pump.
Oil Pump: Gear-type, located in the engine oil pan and driven by the
camshaft.
Oil Capacity: 5 quarts (4.7 liters) including filter.
Oil Filter: Full-flow, spin-on type cartridge or canister-style
replaceable element.
Oil Pressure (operating): 40 to 55 psi at rated speed (2.8 to 3.8 bar).
Minimum acceptable pressure at hot idle is 10 psi (0.7 bar).
Pressure Relief Valve: Integral to the oil pump housing.
Oil Cooler: Not standard equipment on base agricultural models.
The cooling system is a pressurized, pump-circulated system with
thermostatic control.
Water Pump: Centrifugal type, belt-driven from the crankshaft pulley.
Thermostat: Wax-pellet type, begins to open at 180 F (82 C).
Radiator Pressure Cap: 7 psi pressure cap (0.48 bar).
Coolant Capacity: 18.6 quarts (17.6 liters).
Coolant Recommendation: A 50/50 mixture of ethylene glycol antifreeze
and clean, soft water.
Electrical System: 12-volt negative ground.
Starting Motor: 12-volt, solenoid-actuated, high-torque gear reduction
type.
Charging Alternator: 12-volt, 40 to 60 ampere output, belt-driven with
internal or external regulator.
Battery Recommendation: A single 12-volt battery, Group 4D or
equivalent, with minimum 650 cold cranking amps.
Air Intake System: Oil-bath air cleaner. This design requires regular
maintenance, especially in dusty environments. Intake Manifold: Cast
iron. Exhaust Manifold: Cast iron.
Length (front of damper to rear of flywheel housing): 31 inches (787
mm).
Width (over valve cover): 23 inches (584 mm).
Height (top of valve cover to base of oil pan): 27 inches (686 mm).
Weight (dry, as described): 720 lbs (327 kg).
Engine Oil Grade: Use a high-quality diesel engine oil meeting API
service classification CC or CD. SAE 30 is suitable for sustained
operation in temperatures above 40 F (4 C). SAE 10W-30 or 15W-40 can be
used for multi-temperature operation. Oil Change Interval: Under normal
agricultural service, change engine oil and filter every 100 operating
hours. For severe service conditions, reduce interval to 50 hours.
Oil Filter Change: Replace the spin-on filter or canister element with
every oil change. Fuel Filter Change: Drain water and sediment from the
primary bowl daily. Replace the primary and secondary fuel filter
elements every 250 operating hours. Coolant Change: Drain, flush, and
refill the cooling system every 2000 operating hours or 24 months. Check
coolant freeze protection level seasonally.
Air Filter Service: Service the oil-bath air cleaner every 10 hours of
operation under normal conditions. This involves cleaning the wire mesh
element and refilling the oil cup to the marked level with fresh engine
oil. Service daily in extremely dusty conditions. Valve Lash Adjustment:
Check and adjust valve clearance every 500 operating hours.
Injection Timing Check: Verify static injection timing every 1000
operating hours or after any fuel system service that disturbs the pump
drive train. Cylinder Liner Protrusion: During overhaul, measure and
verify wet sleeve protrusion above the block deck. Specification is
0.002 to 0.005 inches (0.05 to 0.13 mm).
Cylinder Head Bolts: Torque in the specified three-step sequence to a
final value of 90 to 95 lb-ft (122 to 129 Nm).
Main Bearing Cap Bolts: 80 to 85 lb-ft (108 to 115 Nm).
Connecting Rod Cap Nuts: 45 to 50 lb-ft (61 to 68 Nm).
Flywheel to Crankshaft Bolts: 75 to 80 lb-ft (102 to 108 Nm).
Injector Nozzle Holder (in head): 35 to 40 lb-ft (47 to 54 Nm).
Rocker Arm Shaft Bracket Bolts: 20 to 25 lb-ft (27 to 34 Nm).
Oil Pan Drain Plug: 25 to 30 lb-ft (34 to 41 Nm).
The International Harvester D188 engine was the designated powerplant
for specific mid-range agricultural and industrial tractors. Its primary
and most common application is in the International Harvester 504
row-crop (Farmall) and standard-tread tractors. It also powered the
industrial counterpart, the International 2504 tractor-loader-backhoe.
This engine was integral to these models, providing the necessary power
for three-point hitch implements, belt work, and power-take-off driven
equipment. The engine was not widely used in other machinery lines,
being closely associated with the 504/2504 platform. Confirmation of
engine model should always be made via the engine serial number plate
located on the block.
____________________________________________________________________________________
| Industrial Engines Technical Specifications |
| Car Engines Technical Specifications |
| Small Engines Technical Specifications |
| Outboard Engines Technical Specifications |
