John Deere 4276D Specifications
| Engine Model: John Deere 4276D |
| Engine Type: 4-stroke in-line 4-cylinder liquid-cooled diesel |
| Total Displacement: 276 cu.in (4.5 L) |
| Rated Engine Power: 74-80 Hp (55-60 kW) at 2500 rpm |
| Fuel System Type: Direct Injection |
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The John Deere 4276D is a naturally aspirated,
4-cylinder diesel engine from the John Deere 400 Series engine family.
Designed for agricultural, construction, and industrial applications,
this power unit is recognized for its durable wet-sleeve cylinder design
and mechanical fuel system. The engine operates without electronic
controls, offering straightforward serviceability in remote locations.
Produced primarily during the 1980s and 1990s, the 4276D powers utility
tractors, backhoes, and crawler dozers. Its long stroke configuration
generates peak torque at low engine speeds, a characteristic suited for
variable load operations. The engine incorporates a Stanadyne rotary
distributor pump, a gear-driven balancer system, and a 5-main bearing
crankshaft. This model preceded the electronically managed 4000 Series
engines, maintaining a reputation for mechanical reliability.
Engine Type: 4-cycle, In-line, 4-cylinder diesel, naturally aspirated
Displacement: 276 cu.in (4.5 L)
Bore x Stroke: 4.19 in x 5.00 in (106.5 mm x 127 mm)
Compression Ratio: 16.8:1
Firing Order: 1-3-4-2
Rotation (facing flywheel): Counterclockwise
Rated Power: 55-60 kW (74-80 hp) at 2500 rpm
Peak Torque: 285 Nm (210 lb-ft) at 1300-1500 rpm
Rated Speed: 2500 rpm
Low Idle Speed: 800-950 rpm
Aspiration: Natural (no turbocharger or supercharger)
Emission Standard: Pre-Euro / Tier 0
The cylinder block is constructed from high-grade cast iron with a
deep-skirt design to support the crankshaft. This engine employs
replaceable wet-sleeve cylinder liners. Each liner is sealed at the
bottom by O-rings and at the top by a fire ring integrated into the
cylinder head gasket. The wet-sleeve design permits coolant to contact
the external liner surface directly, delivering superior heat transfer
from the combustion zone to the cooling system.
The block incorporates five main bearing bulkheads, machined in a single
setup to maintain bore alignment. The crankcase is reinforced with
transverse ribs to reduce vibration under sustained low-speed operation.
Cast-in ports supply oil to the main bearings, connecting rods, and the
optional balancer shaft assembly.
The cylinder head is a single-piece cast iron component with a
cross-flow intake and exhaust port arrangement. It houses the overhead
valve (OHV) system. The valve train includes hydraulic or mechanical
lash adjusters, depending on production year. Each cylinder receives two
valves: one intake and one exhaust. Valve seat inserts are hardened for
wear resistance under high-temperature exposure.
The intake ports are designed to induce swirl, promoting air-fuel mixing
during the compression stroke. Valve stems are chrome-plated to reduce
friction and wear. The rocker arm shaft is mounted on pedestals cast
into the head. Cylinder head bolts thread directly into the block
without using studs. Pre-combustion chambers are absent; combustion
occurs directly in the bowl-in-piston design.
The fuel system is a mechanical direct injection design operating
without electronic control. A Stanadyne (Roosa Master) DB2 or DB4 series
rotary distributor pump meters and delivers fuel. This pump uses a
hydraulic head with a single pumping plunger that rotates and
reciprocates to distribute fuel to each cylinder in firing order
sequence.
A mechanical governor within the pump maintains engine speed against
load variations. Injection lines of equal length deliver fuel to
pencil-type nozzles. The injection nozzles open at a pressure of 180-200
bar (2610-2900 psi). A manual fuel feed pump, mounted on the injection
pump body, primes the system after filter changes. A fuel return line
redirects excess fuel and entrained air to the fuel tank.
The lubrication system uses a gear-type oil pump driven directly from
the crankshaft. Oil is drawn through a suction strainer located in the
oil pan. A full-flow spin-on oil filter removes particulates before oil
enters the main gallery. The system feeds the main bearings, connecting
rod bearings, camshaft bearings, and rocker arm assembly. An oil
pressure relief valve, set at 4.1-4.8 bar (60-70 psi), prevents
over-pressurization during cold starts.
Oil pan capacity ranges from 8.5 to 13.0 L (9.0-13.7 qt), with the
variation determined by oil pan depth and vehicle configuration. Oil
pressure at rated speed is 2.4-3.4 bar (35-50 psi). Low oil pressure at
idle (below 0.7 bar / 10 psi) indicates worn bearings or a failing pump.
The cooling system is pressurized and thermosiphon-assisted, driven by a
belt-mounted centrifugal water pump. Coolant flows from the radiator
into the block, through the water jacket around the wet-sleeve liners,
then upward into the cylinder head, and finally returns to the radiator.
A wax-pellet thermostat, located at the coolant outlet, begins opening
at 82°C (180°F) and is fully open by 95°C (203°F).
Coolant capacity for the engine alone is 8.5 L (9.0 qt). Total system
capacity, including radiator and hoses, ranges from 12.0 to 16.0 L
(12.7-16.9 qt). A removable expansion tank cap permits pressure relief
at 0.7 bar (10 psi). The water pump uses a sealed bearing and a
carbon-ceramic seal. Coolant specification requires low-silicate
ethylene glycol antifreeze at a 50/50 concentration.
Aspiration: Natural aspiration without turbocharger. Air passes through
a dry-type, two-stage paper filter element equipped with a dust
evacuation valve.
Exhaust System: A single exhaust manifold, cast from high-silicon iron,
collects gases from cylinder ports. The manifold mates directly to a
vertical exhaust pipe on most vehicle applications.
Balancer System: A gear-driven balancer shaft, optional on certain
industrial variants, reduces secondary vibration inherent to the
4-cylinder inline configuration. The shaft rotates at twice crankshaft
speed in the opposite direction.
Electrical System: 12-volt (standard) or 24-volt (optional) negative
ground. The starter motor power rating is 2.7 kW (12V) or 3.5 kW (24V).
A 55-amp alternator provides charging capacity. Glow plugs (12V or 24V)
are installed in the intake manifold pre-heater or in each cylinder,
depending on the intake heater configuration.
Length (flywheel to fan pulley): 885 mm (34.8 in)
Width (overall, exhaust manifold to fuel pump): 520 mm (20.5 in)
Height (oil pan rail to rocker cover): 810 mm (31.9 in)
Dry Engine Weight (without starter, alternator, flywheel): 390 kg (860
lb)
Dry Weight (fully dressed): 440 kg (970 lb)
Engine Oil Change Interval: 250 hours or 12 months, whichever occurs
first.
Engine Oil Capacity (standard pan): 8.5 L (9.0 qt).
Engine Oil Capacity (deep pan): 13.0 L (13.7 qt).
Engine Oil Grade: SAE 15W-40, SAE 10W-30 (API CC, CD, or CE).
Engine Oil Pressure at Rated Speed: 2.4-3.4 bar (35-50 psi).
Engine Oil Pressure at Low Idle: 0.7 bar (10 psi) minimum.
Coolant Capacity (engine only): 8.5 L (9.0 qt).
Coolant Capacity (system total): 12.0-16.0 L (12.7-16.9 qt).
Coolant Specification: Ethylene glycol base with low-silicate.
Thermostat Opening Temperature: 82°C (180°F).
Fuel Filter Replacement Interval: 500 hours. Primary and secondary
filters.
Air Filter Service Interval: Check restriction gauge every 100 hours.
Air Filter Service Interval: Replace when gauge indicates blockage or
after 500 hours.
Valve Lash (Intake): 0.30 mm (0.012 in) cold.
Valve Lash (Exhaust): 0.50 mm (0.020 in) cold.
Valve Lash Inspection Interval: 1000 hours.
Injector Nozzle Replacement Interval: 2000 hours.
Injection Pump Timing: 14 deg before top dead center at No. 1 cylinder.
Cylinder Liner Protrusion: 0.03-0.13 mm (0.001-0.005 in) above block
surface.
Idle Speed Adjustment: Low idle 800-950 rpm.
Idle Speed Adjustment: High idle governed at 2650-2700 rpm no-load.
Cylinder Head Bolts (final step): 150 Nm (110 lb-ft).
Connecting Rod Cap Bolts: 90 Nm (65 lb-ft)
Main Bearing Cap Bolts: 115 Nm (85 lb-ft)
Crankshaft Main Bearing Cap Bolts (side bolts): 70 Nm (52 lb-ft)
Flywheel Bolts (to crankshaft flange): 115 Nm (85 lb-ft)
Flywheel Housing Bolts (to block): 80 Nm (59 lb-ft)
Camshaft Thrust Plate Bolts: 25 Nm (18 lb-ft)
Rocker Arm Shaft Pedestal Bolts: 35 Nm (26 lb-ft)
Valve Cover Nuts: 10 Nm (7 lb-ft)
Injection Pump Drive Gear Nut: 100 Nm (74 lb-ft)
Injection Line Fittings (at pump and nozzle): 30 Nm (22 lb-ft)
Crankshaft Pulley Bolts: 45 Nm (33 lb-ft)
Oil Pan Bolts (M8): 20 Nm (15 lb-ft)
Oil Pan Drain Plug: 45 Nm (33 lb-ft)
Water Pump Mounting Bolts: 25 Nm (18 lb-ft)
Thermostat Housing Bolts: 15 Nm (11 lb-ft)
Starter Motor Mounting Bolts: 50 Nm (37 lb-ft)
Glow Plug (in-cylinder type): 20 Nm (15 lb-ft)
Tractors: John Deere 2550, 2750, 2355, 2555, 2755 utility tractors.
These models used the 4276D from 1983 to 1992.
Construction: JD 410B, 410C, 510B backhoe loaders. JD 450E, 450G crawler
dozers. JD 444, 544B wheel loaders.
Industrial: Power units for irrigation pumps (John Deere 4276D PU
series). Stationary generator sets rated at 40-55 kW continuous.
Industrial compressors and wood chippers.
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