Caterpillarexcavator
Caterpillar EL300
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar EL300 is a 30-ton class crawler excavator built during the Caterpillar-Mitsubishi joint-venture era (Shin Caterpillar Mitsubishi, Akashi, Japan), with production running roughly 1987 to 1993 under serial prefix 4NF. Operating weight runs approximately 31,615 kg (69,700 lb), varying with undercarriage and boom/stick configuration, with transport dimensions of roughly 10.95 m x 3.40 m x 3.23 m (35 ft 11 in x 11 ft 2 in x 10 ft 7 in). Power comes from a Cat 3306 inline-6, 10.5-liter, direct-injection, turbocharged diesel rated at roughly 140 kW (187 hp) flywheel, mechanically governed with no ECM, so all monitoring is through analog gauges and warning lamps rather than digital fault codes. The EL300 was offered with fixed-gauge and variable-gauge long undercarriage options and standard boom/stick combinations; it followed the earlier E300 in the same Akashi-designed excavator family, while the later EL300B is a distinct, heavier machine on its own serial prefix rather than a running change of the EL300.
Across this generation the core engineering shifted from Mitsubishi-designed excavator platforms toward Caterpillar's own 3306 diesel and hydraulic architecture, part of the broader move that folded the Akashi excavator design center fully into Caterpillar's global product line. The EL300 sits at that transition: a mechanically simple, pre-electronic machine that predates Cat's modern work-tool catalog and PM-tier maintenance system, so class-level 30-ton attachment norms apply rather than a factory EL300-specific tool catalog. In the used and parts market today it holds value for that same simplicity — no ECM to fail, a 3306 engine shared across a wide range of Cat machines and generators that keeps wear parts and rebuild kits available, and a rugged undercarriage that tolerates aftermarket track and roller cross-references even though Caterpillar's own literature for this exact serial range is limited.
Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.
Caterpillar EL300 specifications
Engine
| Engine model | Cat 3306 diesel, inline-6, direct injection, turbocharged |
| Displacement | 10.5 L (638 cu in) |
| Cylinders | 6 |
| Gross/net power | Not confirmed for this exact configuration (prefix 4NF) — published figures belong to the later B-series relaunch; verify with your dealer or the OEM service manual before quoting a number |
| Emissions tier | Mechanical diesel predating emissions-tier regulation; no EPA/EU tier rating applies |
Weights
| Operating weight (standard) | 31,615 kg (69,700 lb) |
| Ground pressure | Not documented for this configuration — verify with your dealer |
| Transport weight | Not documented separately from operating weight in available sources |
Dimensions
| Transport length | 10.95 m (35 ft 11 in) |
| Transport width | 3.40 m (11 ft 2 in) |
| Transport height | 3.23 m (10 ft 7 in) |
| Tail swing radius, track shoe width, ground clearance, undercarriage length | Not documented for this configuration — verify with your dealer or OEM service manual |
Performance
| Max dig depth, max reach, max dump height, max cutting height, swing speed, travel speed, gradeability, drawbar pull | Not documented for this configuration in available sources — verify with your dealer or OEM service/operation manual |
Forces
| Bucket and stick/arm digging force | Not documented for this configuration in available sources — verify with your dealer or OEM service manual |
Service capacities (summary)
| Fuel tank, hydraulic system, engine oil, cooling system | Not documented distinctly for this base configuration; figures found online for the later B-series relaunch are not confirmed to carry over and are not quoted here |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
EL300 fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | Not published in any available source for this serial range. Verify against the machine's own operation and maintenance manual or a dealer before servicing. | Cat Diesel Engine Oil (Cat DEO), multigrade, selected by ambient temperature per the standard Cat engine oil viscosity chart. No EL300-specific viscosity-by-climate table is available in open sources. |
| Cooling system | Not published in any available source for this serial range. Verify against the OMM or a dealer. | Cat coolant/antifreeze meeting Cat's heavy-duty cooling system spec (Cat ELC or an equivalent full-formula, low-silicate coolant). No EL300-specific mix ratio is documented in open sources. |
| Fuel tank | Not published in any available source for this serial range. Verify against the OMM or a dealer. | Diesel fuel meeting Cat's standard distillate fuel specification for the era's mechanical fuel system. |
| Hydraulic system total AND hydraulic tank | Not published in any available source for this serial range. Verify against the OMM or a dealer. | Cat hydraulic oil (Cat HYDO-class or Cat TDTO-class fluid, as specified for this machine class) graded by ambient temperature. No EL300-specific viscosity-by-climate table is available in open sources. |
| Final drive (each) | Not published in any available source for this serial range. Verify against the OMM or a dealer. | Cat TDTO (Transmission/Drivetrain Oil)-class gear oil, per Cat's standard final-drive fill spec for this machine class. |
| Swing drive | Not published in any available source for this serial range. Verify against the OMM or a dealer. | Cat TDTO-class gear oil, per Cat's standard swing-drive fill spec for this machine class. |
| Pilot/other circuits | No separate pilot-circuit fill is documented; pilot oil is typically drawn from the main hydraulic tank on this machine class. | Same hydraulic oil as the main hydraulic system. |
| Grease (spec only) | Not applicable (grease points serviced by count/interval, not a bulk fill). | Cat multipurpose or moly-fortified chassis grease (Cat MPGM-class), applied at pins, bushings, and the swing gear/bearing per standard lube points. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar EL300 maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 50 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
| Every 6,000 h |
|
Servicing the EL300 beyond the schedule
Predictive Maintenance & Fluid Analysis
With no ECM on the 3306, there are no fault codes to trend, so oil, coolant, and hydraulic sampling carry the diagnostic load. Watch engine oil for iron and copper trending up, an early flag for injection pump or turbocharger bearing wear. Sample hydraulic oil for pump and motor wear metals before the main pump loses flow. Check coolant corrosion inhibitor levels regularly since this mechanically-injected DI engine runs hot and is unforgiving of neglected coolant chemistry.
Corrective & Common Repairs
Typical EL300 complaints trace to the mechanical fuel system: worn injectors and injection pump linkage cause hard starting, smoke, and power loss. Turbocharger shaft play and boost leaks show up as sluggish response. Swing bearing and swing gear wear produce play or noise on rotation. On the hydraulic side, main pump and relief valve drift cause slow cycle times. Undercarriage wear (track chain stretch, sprocket and roller wear) is common given the machine's age and duty history.
Overhaul & Rebuild Points
Plan engine top-end work — injector replacement, turbocharger rebuild, valve lash and injection timing reset — as oil consumption or smoke trends worsen, typically well past the 4000-hour mark on a well-maintained unit. Main hydraulic pump and swing motor rebuilds follow flow-loss trends from sampling rather than a fixed hour number. Undercarriage is usually the biggest rebuild line item on a machine this age: track chain, rollers, idlers, and sprockets wear as a set and are best evaluated together.
Seasonal & Environment Servicing
Cold-weather starts on this mechanical DI engine benefit from an ether-assist or block heater and correctly rated winter fuel, since there is no electronic cold-start strategy to compensate. In hot or dusty environments, clean the radiator and oil cooler cores more often and shorten air filter service intervals to protect the turbocharger. In wet or abrasive ground conditions, increase undercarriage cleaning frequency and grease intervals to slow track pin and bushing wear.
EL300 fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Engine Oil Pressure warning lamp (red) | Engine oil pressure at the sending unit has dropped below the safe minimum. | Low oil level, worn oil pump, clogged suction screen, or a failed pressure switch. | Stop the engine immediately, check oil level, and inspect the pressure switch before restart. |
| Coolant Temperature warning lamp (red) | Engine coolant temperature has exceeded the safe operating range. | Low coolant level, blocked radiator core, slipping or broken fan belt, or a failed thermostat. | Idle down, shut off the engine once safe, let it cool, then check coolant level and radiator fins before restart. |
| Alternator/Charging System warning lamp (red) | Battery is not receiving charge from the alternator. | Broken or slipping alternator belt, failed alternator, or a loose or corroded battery connection. | Check belt tension and battery terminals; test alternator output if the lamp stays lit with the engine running. |
| Air Cleaner Restriction indicator | Intake air filter restriction has reached the service limit. | Clogged primary air filter element from dust or debris buildup. | Service or replace the primary air filter element and reset the restriction indicator. |
| Hydraulic Oil Temperature gauge - high reading | Hydraulic system oil temperature is running above normal operating range. | Low hydraulic fluid level, clogged oil cooler fins, or sustained high-load operation in hot ambient conditions. | Reduce load, check hydraulic fluid level, and clean the oil cooler core. |
| Hydraulic Filter Bypass/Restriction indicator | Return hydraulic filter has reached bypass restriction, letting unfiltered oil circulate. | Clogged hydraulic return filter element from normal wear or fluid contamination. | Replace the hydraulic return filter element at the next scheduled service, or immediately if the indicator stays active. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
EL300 attachments & work tools
Buckets
EL300 is a 30-ton class machine (about 31.6 t / 69,700 lb operating weight) built through the 1987-1993 run. General-duty buckets for this class typically run roughly 1.0-1.5 m3 heaped, with heavy-duty/rock buckets narrower at roughly 0.8-1.2 m3 for reinforced wall thickness, in widths from about 900 mm to 1500 mm (36-60 in). All factory mounting on this machine is pin-on; exact bucket pin diameter is not documented for this specific model and should be field-measured before ordering a bucket.
Hydraulic hammers
For a 30-ton class carrier, breaker service weight class runs roughly 1,500-2,500 kg (3,300-5,500 lb), in line with medium-large hammer classes built for 19-32 t carriers. The base machine's factory hydraulic circuit was not pre-plumbed for a breaker; fitting one calls for a dedicated auxiliary line sized to the hammer maker's flow and pressure requirement.
Quick couplers
EL300 predates factory quick-coupler options on Cat excavators, so any coupler is an aftermarket fitment, typically a mechanical pin-grabber (wedge) type sized to the machine's 30-ton class stick and bucket pin centers. Hydraulic (powered) couplers are not confirmed for this model and would need their own dedicated hydraulic circuit not present on the base machine.
Thumbs/grapples
Hydraulic thumbs and grapples for this weight class mount to the stick and share the bucket pin, sized to a 30-ton carrier. No EL300-specific thumb or grapple kit is documented; fitment is aftermarket and depends on field-measured stick width and pin diameter.
Rippers
A single-shank ripper sized for a 30-ton class carrier is a common aftermarket fitment for machines this size, mounting in place of the bucket at the stick pin. No EL300-specific ripper kit or performance rating is documented for this model.
Hydraulic-kit notes
The EL300 runs a variable-flow, pilot-operated hydraulic system typical of its era, rated around 140 kW (187 hp) at the flywheel. Running a hammer, thumb, or other tool that needs continuous auxiliary flow requires adding a dedicated medium-pressure circuit, since this was not standard on the base machine; confirm pump flow and relief pressure against the tool's spec before fitting, and verify locally given the machine's age.
All EL300 assemblies by section
Every catalogued assembly group for the Caterpillar EL300. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Basic Engine
2w7458 Crankshaft As*R
| 2W***58 | Crankshaft As | 1 |
1n4406 Camshaft Gp-Single
| 1N***06 | Camshaft Group-Single; Camshaft Group--Single | 1 |
7n1342 Cover Gp-Cylinder Block
| 7N***42 | Cover Group-Cylinder Block; Cylinder Block Cover Group | 1 |
2p6530 Cover Gp-Cylinder Head
| 2P***30 | Cover Group-Cylinder Head; Cylinder Head Cover Group | 1 |
2p6529 Cover Gp-Front Housing
| 2P***29 | Cover Group-Front Housing; Front Housing Cover Group | 1 |
8n4745 Cover Gp-Valve Mechanism
| 8N***45 | Cover Group-Valve Mechanism; Valve Mechanism Cover Group | 1 |
6n8079 Crankshaft Gp
| 6N***79 | Crankshaft Group; Crankshaft Group | 1 |
7n6550 Cylinder Block As
| 7N***50 | Cylinder Block As | 1 |
8n5286 Cylinder Block Gp*R
| 8N***86 | Cylinder Block Group; Cylinder Block Group | 1 |
1n3576 Cylinder Block Gp
| 1N***76 | Cylinder Block Group | 1 |
7n8876 Cylinder Head Gp*R
| 7N***76 | Cylinder Head Group; Cylinder Head Group | 1 |
1w7733 Damper Gp
| 1W***33 | Damper Group; Damper Group | 1 |
7c6554 Drive Gp-Fan
| 7C***54 | Drive Group-Fan; Fan Drive Group | 1 |
7n9536 Fastener Gp-Cylinder Head
| 7N***36 | Fastener Group-Cylinder Head; Cylindetr Head Fastener Group | 1 |
8n872 Fastener Gp-Front Housing
| 8N***72 | Fastener Group-Front Housing; Front Housing Fastener Group | 1 |
2p6199 Fastener Gp-Oil Pan
| 2P***99 | Fastener Group-Oil Pan; Oil Pan Fastener Group | 1 |
7c4441 Flywheel Gp
| 7C***41 | Flywheel Group; Flywheel Group | 1 |
1w5634 Gear Gp-Front Timing
| 1W***34 | Gear Group-Front Timing; Front Gear Group--Timing | 1 |
8n2395 Housing Gp-Flywheel
| 8N***95 | Housing Group-Flywheel; Flywheel Housing Group | 1 |
8n0303 Housing Gp-Front
| 8N***03 | Housing Group-Front; Front Housing Group | 1 |
8n3157 Lifting Gp-Engine
| 8N***57 | Lifting Group; Engine Lifting Group | 1 |
9y2062 Lifting Gp-Engine
| 9Y***62 | Lifting Group-Engine; Engine Lifting Group | 1 |
8n9243 Pan Gp-Oil
| 8N***43 | Pan Group-Oil; Oil Pan Group | 1 |
2w1177 Rod & Piston Gp-6 Required*R
| 2W***77 | Piston & Rod Group; Connecting Rod And Piston Group | 1 |
7n2879 Pulley Gp-Crankshaft
| 7N***79 | Pulley Group-Crankshaft; Crankshaft Pulley Group | 1 |
2p6224 Seal Gp-Crankshaft
| 2P***24 | Seal Group-Crankshaft; Crankshaft Seal Group | 1 |
7c6566 Support Gp-Engine
| 7C***66 | Support Group-Engine; Engine Support Group | 1 |
8n0107 Trunnion Gp-Engine
| 8N***07 | Trunnion Group-Engine; Engine Trunnion Group | 1 |
7c7013 Valve Mechanism Gp
| 7C***13 | Valve Mechanism Group | 1 |
7n8026 Valve Mechanism Gp-Type 2
| 7N***26 | Valve Mechanism Group; Valve Mechanism Group | 1 |
7n8026 Valve Mechanism Gp-Type 1
| 7N***26 | Valve Mechanism Group; Valve Mechanism Group | 1 |
Cooling
8n4457 Base Gp-Oil Filter
| 8N***57 | Base Group-Oil Filter; Base Group-Engine Oil Filter | 1 |
2w6953 Cooler Gp-Filter Base & Engine Oil
| 2W***53 | Cooler Group-Filter Base & Eng Oil | 1 |
2w6954 Cooler Gp-Filter Base & Engine Oil
| 2W***54 | Cooler Group-Filter Base & Eng Oil | 1 |
8n0888 Housing & Regulator Gp
| 8N***88 | Housing & Regulator Group; -Coolant | 1 |
2w6779 Lines Gp-Water
| 2W***79 | Lines Group-Water | 1 |
7n5908 Pump Gp-Water
| 7N***08 | Pump Group-Water | 1 |
2w8002 Pump Gp-Water*R
| 2W***02 | Pump Group-Water; Water Pump (Assembly) | 1 |
Engine Arrangement
7c4447 Engine Ar-Part 2 Of 2
| 2P***84 | Pump Group-Engine Oil; Engine Oil Pump Group | 1 |
| 2P***24 | Seal Group-Crankshaft; Crankshaft Seal Group | 1 |
| 2W***77 | Piston & Rod Group; Connecting Rod And Piston Group | 6 |
7c4447 Engine Ar-Part 1 Of 2
| 1N***06 | Camshaft Group-Single; Camshaft Group--Single | 1 |
| 1P***44 | Breather Group | 1 |
| 1W***34 | Gear Group-Front Timing; Front Gear Group--Timing | 1 |
Engine Ar-General
| 1S***27 | V-Belt Set; (Includes 2-Belts) | 1 |
| 7C***47 | Engine Ar | 1 |
| 7C***50 | Sender Group | 1 |
Excavator
9w8565 Sidecutter Gp-Blade
| 9W***65 | Sidecutter Group-Blade; Sidecutter Gp-Blade | 1 |
9w8566 Sidecutter Gp-Combination
| 9W***66 | Sidecutter Group-Combination | 1 |
9w8567 Sidecutter Gp-Strike Off
| 9W***67 | Sidecutter Group-Strike Off | 1 |
9w8568 Sidecutter Gp-Tooth
| 9W***68 | Sidecutter Group-Tooth | 1 |
6y2863 Tooth Gp
| 6Y***63 | Tooth Group | 1 |
Accumulator
Adjuster Cylinder
Air Cleaner
Air Conditioner - Part 1 Of 3
Air Conditioner - Part 3 Of 3
Air Conditioner - Part 2 Of 3
Air Conditioner Condenser
Air Conditioner Harness
Air Conditioner Lines - Part 2 Of 2
Air Conditioner Lines - Part 1 Of 2
Air Conditioner Receiver
Air Supply Lines (2cf00124-4nf00308-) Part 1 Of 2
Air Supply Lines (2cf1-00123 4nf1-00307) Part 1 Of 2
Air Supply Lines (2cf1-00123 4nf1-00307) - Part 2 Of 2
Air Supply Lines (2cf00124-4nf00308-) - Part 2 Of 2
Am/Fm Radio
Arm And Bucket Lines - Part 2 Of 2
Arm And Bucket Lines - Part 1 Of 2
Arm Cylinder Part 1 Of 2
Arm Cylinder - Part 2 Of 2
Arm Lines (For Side Piping Type)
Arm Lines (For Upper Piping Type)
Arm Pilot Lines (For Breaker-Side Piping Type)
Arm Pilot Lines (For Breaker-Upper Piping Type)
Auto Lock (2cf1-00174 4nf1-00586)
Base Frame
Boom And Accessories - Part 3 Of 3
Boom And Accessories (For Breaker And Double Acting Actuators) - Part 2 Of 2
Boom And Accessories (For Breaker And Double Acting Actuators) - Part 1 Of 2
Boom And Accessories - Part 1 Of 3
Boom And Accessories Part 2 Of 3
Boom Cylinder - Part 2 Of 2
Boom Cylinder - Part 1 Of 2
Boom Light And Harness
Boom Lines - Part 1 Of 2
Boom Lines (For Breaker And Double Acting Actuators)
Boom Lines - Part 2 Of 2
Boom Pilot Lines (For Breaker)
Breaker Switch And Harness (For Speed Control)
9c4316 Bucket As
| 9C***16 | Bucket As | 1 |
9c4318 Bucket As
| 9C***18 | Bucket As | 1 |
Bucket Cylinder - Part 1 Of 2
Bucket Cylinder - Part 2 Of 2
Bucket With Ripper-Sae 1-1/8 Cubic Yard (Jis 0.8 Cubic Meter)
Bucket-Sae 1-1/2 Cubic Yard (Jis 1.0 Cubic Meter)
Bucket-Sae 1-3/4 Cubic Yard (Jis 1.2 Cubic Meter)
Bucket-Sae 2-1/8 Cubic Yard (Jis 1.4 Cubic Meter)
Bucket-Sae 2-3/8 Cubic Yard (Jis 1.6 Cubic Meter)
By-Pass Filter
Cab (Frame) Part 1e Of 4
Cab (Interior Parts) Part 4a Of 4
Cab (Frame) - Part 1d Of 4
Cab (Door And Window Frame) Part 2d Of 4
Cab (Door And Window Frame) Part 2b Of 4
Cab (Frame) - Part 1c Of 4
Cab (Glass And Corner Rubber) Part 3 Of 4
Cab (Interior Parts) Part 4 Of 4
Cab (Glass And Corner Rubber) Part 3b Of 4
Cab (Door And Window Frame) Part 2 Of 4
Cab (Interior Parts) - Part 4b Of 4
Cab (Door And Window Frame) Part 2a Of 4
Cab (Door And Window Frame) Part 2c Of 4
Cab (Frame) - Part 1 Of 4
Cab (Glass And Corner Rubber) Part 3a Of 4
Cab (Frame) - Part 1a Of 4
Cab (Frame) - Part 1b Of 4
Cab Heater
Cab Heater (For Cold Weather)
Carrier Roller
Check Valve
7t8600 Compressor Gp-Clutch & Refrigerant
| 7T***00 | Compressor Group-Clutch & Refrig | 1 |
7c4246 Compressor Gp-Refrigerant
| 7C***46 | Compressor Group-Refrigerant | 1 |
Control Valve A - Part 1 Of 3
Control Valve A - Part 3 Of 3
Control Valve A - Part 2 Of 3
Control Valve B - Part 3 Of 3
Control Valve B - Part 2 Of 3
Control Valve B - Part 1 Of 3
Controls (For Double Acting Actuators)
Controls - Part 1a Of 2
Controls - Part 2 Of 2
Controls (For Breaker)
Controls - Part 1 Of 2
Controls (For Swing Fine Control)
Cross Over Relief Valve - Part 2 Of 2
Cross Over Relief Valve - Part 1 Of 2
Delivery Lines - Part 1 Of 3
Delivery Lines - Part 2 Of 3
Delivery Lines - Part 3 Of 3
Drain Lines - Part 2 Of 3
Drain Lines - Part 3 Of 3
Drain Lines - Part 1 Of 3
7c2162 Drive Gp-Auxiliary
| 7C***62 | Drive Group-Auxiliary; -Lower | 1 |
Electric Parts Part 1 Of 2
Electric Parts - Part 2 Of 2
Engine - Part 1 Of 5
Engine - Part 3 Of 5
Engine - Part 4 Of 5
Engine (For Cold Weather) - Part 2 Of 2
Engine - Part 2 Of 5
Engine Part 5 Of 5
Engine - Part 1 Of 2
Engine - Part 2 Of 2
Engine (For Cold Weather) - Part 1 Of 2
Engine Control (For Automatic Engine Speed Control) - Part 1 Of 2
Engine Control (For Automatic Engine Speed Control) - Part 2 Of 2
Engine Control
Engine Hood - Part 3 Of 4
Engine Hood - Part 2 Of 4
Engine Hood - Part 4 Of 4
Engine Hood - Part 1 Of 4
Ether Starting Aid - Part 1 Of 2
Ether Starting Aid - Part 2 Of 2
Filter Regulator
Front Lines - Part 1 Of 2
Front Lines - Part 2 Of 2
Front Lubrication Lines
Fuel Feed System
Fuel Pump
Fuel Tank And Fuel Lines Part 2 Of 3
Fuel Tank And Fuel Lines - Part 3 Of 3
Fuel Tank And Fuel Lines - Part 1 Of 3
Gear Pump
Grab Bucket Cylinder - Part 1 Of 2
Grab Bucket Cylinder - Part 2 Of 2
Grease Bath
Hand Rail And Side Mirror
Head Guard
Hydraulic Tank - Part 2 Of 2
Hydraulic Tank - Part 1 Of 2
Idler Wheel
Link And Rod - Part 2 Of 2
Link And Rod Part 1 Of 2
Long Arm-13'4" (4055 Mm) - Part 3 Of 3
Long Arm-13'4" (4055 Mm) (For Breaker And Double Acting Actuators) - Part 2 Of 2
Long Arm-13'4" (4055 Mm) (For Breaker And Double Acting Actuators) - Part 1 Of 2
Long Arm-13'4" (4055 Mm) Part 2 Of 3
Long Arm-13'4" (4055 Mm) - Part 1 Of 3
Long Arm Lubrication Lines
Lower Structure Cover
Main Pump - Part 6 Of 7
Main Pump - Part 5 Of 7
Main Pump - Part 4 Of 7
Main Pump - Part 7 Of 7
Main Pump - Part 2 Of 7
Main Pump - Part 1 Of 7
Main Pump Part 3 Of 7
Name Plate And Label (Body)
Name Plate And Label (Cab)
Name Plate And Label (For Automatic Engine Speed Control)
P.T.O. Valve - Part 1 Of 2
P.T.O. Valve - Part 2 Of 2
Pilot Filter
Pilot Lines (For Breaker)
Pilot Lines (For Double Acting Actuators)
Pilot Valve
Pilot Valve (For Double Acting Actuators)
Pilot Valve (For Breaker)
9c9317 Bucket As
Pump Drive
Pump Drive Gear - Part 1 Of 2
Pump Drive Gear - Part 2 Of 2
Pump Installation
Pump Suction Lines
Radiator - Part 2 Of 2
Radiator Part 1 Of 2
Radiator Baffle Plate
Radio Mantle
Relay Box
Relay Box (For Automatic Engine Speed Control And Swing Parking Brake) Part 1 Of 2
Relay Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 2 Of 2
Relief Valve
Relief Valve (For Breaker)
Relief Valve (For Double Acting Actuators)
Remote Control Valve - Part 2 Of 2
Remote Control Valve - Part 1 Of 2
Return Check Valve
Return Lines - Part 1 Of 3
Return Lines - Part 3 Of 3
Return Lines - Part 2 Of 3
Ripper
Rotary Joint
Rotating Grab Bucket-Sae 1-5/8 Cubic Yards (Jis 1.2 Cubic Meters) - Part 2 Of 3
Rotating Grab Bucket-Sae 1 Cubic Yards (Jis 0.8 Cubic Meters) - Part 2 Of 3
Rotating Grab Bucket-Sae 1-1/4 Cubic Yards (Jis 1.0 Cubic Meters) - Part 2 Of 3
Rotating Grab Bucket-Sae 1 Cubic Yards (Jis 0.8 Cubic Meters) - Part 1 Of 3
Rotating Grab Bucket-Sae 1-1/4 Cubic Yards (Jis 1.0 Cubic Meters)-Part 3 Of 3
Rotating Grab Bucket-Sae 1-1/4 Cubic Yards (Jis 1.0 Cubic Meters) - Part 1 Of 3
Rotating Grab Bucket-Sae 1-5/8 Cubic Yards (Jis 1.2 Cubic Meters)-Part 3 Of 3
Rotating Grab Bucket-Sae 1-5/8 Cubic Yards (Jis 1.2 Cubic Meters) - Part 1 Of 3
Rotating Grab Bucket-Sae 1 Cubic Yards (Jis 0.8 Cubic Meters) - Part 3 Of 3
Safety Lock Valve (2cf00252-4nf00779-)
Seat And Floor Mat - Part 1 Of 2
Seat And Floor Mat - Part 2 Of 2
Seat Belt
Servo And Pilot Lines (For Swing Fine Control)
Servo And Pilot Lines (For Swing Parking Brake)
Servo And Pilot Lines - Part 3 Of 3
Servo And Pilot Lines (Part 4 Of 4) (For Automatic Engine Speed Control)
Servo And Pilot Lines - Part 1b Of 3
Servo And Pilot Lines - Part 1a Of 3
Servo And Pilot Lines - Part 2 Of 3
Servo And Pilot Lines - Part 1c Of 3
Servo And Pilot Lines (Part 3 Of 4) (For Automatic Engine Speed Control)
Servo And Pilot Lines - Part 1 Of 3
Servo And Pilot Lines (Part 1 Of 4) (For Automatic Engine Speed Control)
Servo And Pilot Lines - Part 2a Of 3
Servo And Pilot Lines (Part 2 Of 4) (For Automatic Engine Speed Control)
Short Arm-9'7" (2915 Mm) - Part 2 Of 2
Short Arm-9'7" (2915 Mm) (For Breaker And Double Acting Actuators) - Part 2 Of 2
Short Arm-9'7" (2915 Mm) (For Breaker And Double Acting Actuators) - Part 1 Of 2
Short Arm-9'7" (2915 Mm) - Part 1 Of 2
Shut Off Valve (2cf1-00251 4nf1-00778)
Shuttle Valve
Slow Return Valve
Solenoid Valve
Solenoid Valve (For Swing Fine Control)
Solenoid Valve (For Swing Parking Brake)
Swing Bearing Lubrication Lines
Swing Brake (For Swing Parking Brake) (2cf1-00101 4nf1-00103)
Swing Control Valve - Part 2 Of 2
Swing Control Valve - Part 1 Of 2
Swing Drive (2cf1-00101 4nf1-00103)-Part 1 Of 2
Swing Drive (For Swing Parking Brake) (2cf1-00101 4nf1-00103)
Swing Drive (2cf00102-4nf00104-) - Part 2 Of 2
Swing Drive (2cf1-00101 4nf1-00103)-Part 2 Of 2
Swing Drive (2cf00102-4nf00104-) - Part 1 Of 2
Swing Drive (For Swing Parking Brake) (2cf00102- 4nf00104-)
Swing Frame And Counter Weight - Part 2 Of 2
Swing Frame And Counter Weight - Part 1 Of 2
Swing Frame Cover (Support)
Swing Frame Cover (Side) - Part 4 Of 4
Swing Frame Cover (Side) - Part 2 Of 4
Swing Frame Cover (Side) - Part 1 Of 4
Swing Frame Cover (Under)
Swing Frame Cover (Side) - Part 3 Of 4
Swing Frame Cover (Upper)
Swing Gear (2cf00102- 4nf00104-)-Part 2 Of 2
Swing Gear (2cf00102- 4nf00104-) Part 1 Of 2
Swing Gear (2cf1-00101 4nf1-00103) - Part 1 Of 2
Swing Gear (2cf1-00101 4nf1-00103) - Part 2 Of 2
Swing Motor (For Swing Parking Brake) (2cf00102- 4nf00104-) - Part 1 Of 3
Swing Motor (2cf00102- 4nf00104-) - Part 2 Of 3
Swing Motor (2cf00102- 4nf00104-) - Part 1 Of 3
Swing Motor (2cf1-00101 4nf1-00103) - Part 2 Of 2
Swing Motor (For Swing Parking Brake) (2cf00102- 4nf00104-) - Part 2 Of 3
Swing Motor (For Swing Parking Brake) (2cf00102- 4nf00104-) - Part 3 Of 3
Swing Motor (2cf00102- 4nf00104-) - Part 3 Of 3
Swing Motor (2cf1-00101 4nf1-00103) - Part 1 Of 2
Swing Pump Part 3 Of 8
Swing Pump - Part 8 Of 8
Swing Pump - Part 1 Of 8
Swing Pump - Part 7 Of 8
Swing Pump Part 4 Of 8
Swing Pump - Part 5 Of 8
Swing Pump - Part 2 Of 8
Swing Pump - Part 6 Of 8
Switch Box (Meter Unit) - Part 2 Of 3
Switch Box (Panel) Part 1 Of 3
Switch Box (Body) - Part 3a Of 3
Switch Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 4 Of 6
Switch Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 6 Of 6
Switch Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 5 Of 6
Switch Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 3 Of 6
Switch Box (Body) - Part 3 Of 3
Switch Box (Panel) - Part 1a Of 3
Switch Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 1 Of 6
Switch Box (For Automatic Engine Speed Control And Swing Parking Brake) - Part 2 Of 6
9n4566 Tip Gp-Sharp-Center
| 9N***66 | Tip Group; -J-460 | 1 |
3g3351 Tip Gp-Penetration
| 3G***51 | Tip Group | 1 |
9w6474 Tip Gp-Sharp Center
| 9W***74 | Tip Group | 1 |
9n4565 Tip Gp-Sharp-Corner
| 9N***65 | Tip Group; -J-460 | 1 |
8j9170 Tip Group-Wide
| 8J***70 | Tip Group | 1 |
9w6475 Tip Gp-Sharp Corner
| 9W***75 | Tip Group-Corner | 1 |
8j9172 Tip Gp-Long
| 8J***72 | Tip Group-Long; -4 Required | 1 |
9n4562 Tip Gp-Long
| 9N***62 | Tip Group-Long; -J-460 | 1 |
9n4564 Tip Gp-Penetration
| 9N***64 | Tip Group-Penetration; -J-450 | 1 |
8j9171 Tip Gp-Short
| 8J***71 | Tip Group-Short | 1 |
9n4560 Tip Gp-Wide
| 9N***60 | Tip Group-Wide; -J-460 | 1 |
Tool Box
Tools - Part 1 Of 2
Tools - Part 2 Of 2
Track 23-5/8" (600 Mm) Triple Grouser Shoes
Track 35-7/8" (910 Mm) Triple Grouser Shoes
Track 23-5/8" (600 Mm) Triple Grouser Shoes (Sealed Type)
Track 31-1/2" (800 Mm) Triple Grouser Shoes--Part 1 Of 2
Track 31-1/2" (800 Mm) Triple Grouser Shoes
Track 31-1/2" (800 Mm) Triple Grouser Shoes (Sealed Type)
Track 35-7/8" (910 Mm) Triple Grouser Shoes (Sealed Type)
Track 31-1/2" (800 Mm) Triple Grouser Shoes - Part 2 Of 2
Track 23-5/8" (600 Mm) Triple Grouser Shoes - Part 2 Of 2
Track 23-5/8" (600 Mm) Triple Grouser Shoes - Part 1 Of 2
Track Roller
Travel Brake Valve
Travel Drive And Sprocket
Travel Gear - Part 3 Of 3
Travel Gear - Part 1 Of 3
Travel Gear - Part 2 Of 3
Travel Lines - Part 2 Of 2
Travel Lines - Part 1 Of 2
Travel Motor Part 1 Of 5
Travel Motor - Part 4 Of 5
Travel Motor - Part 5 Of 5
Travel Motor - Part 2 Of 5
Travel Motor Part 3 Of 5
Travel Motor Lines - Part 3 Of 3
Travel Motor Lines - Part 2 Of 3
Travel Motor Lines - Part 1 Of 3
Upper Structure Lines (For Double Acting Actuators)
Upper Structure Lines (For Breaker)
Vandalism Guard
Water Separator
Window Washer
Wiper Motor
Wiring Harness (For Automatic Engine Speed Control) (4nf1-00148) - Part 1 Of 2
Wiring Harness (For Automatic Engine Speed Control) (4nf1-00148) - Part 2 Of 2
Wiring Harness - Part 3 Of 3
Wiring Harness (For Swing Fine Control)
Wiring Harness - Part 1 Of 3
Wiring Harness - Part 2 Of 3
Yoke And Tension
Fuel System And Governor
7c8993 Fastener Gp
| 7C***93 | Fastener Group-Fuel Inj Pump | 1 |
1w3597 Torque Control Gp-Type 2
| 1W***97 | Torque Control Group | 1 |
1w3597 Torque Control Gp-Type 1
| 1W***97 | Torque Control Group | 1 |
2w0255 Camshaft As
| 2W***55 | Camshaft As | 1 |
8n2177 Control Gp-Governor
| 8N***77 | Control Group-Governor; Governor Control Group | 1 |
7c4448 Governor & Fuel Injection Pump Gp
| 7C***48 | Gov & Fuel Inj Pump Group; Pump Gp-Governor & Fuel Inj | 1 |
2w2410 Governor Gp-Part 1 Of 3
| 2W***10 | Governor Group | 1 |
2w2410 Governor Gp-Part 3 Of 3
| 2W***10 | Governor Group | 1 |
2w2410 Governor Gp-Part 2 Of 3
| 2W***10 | Governor Group | 1 |
1w3487 Housing As-Fuel Pump
| 1W***87 | Housing As-Fuel Pump | 1 |
2w3249 Lines Gp-Fuel Injection
| 2W***49 | Lines Group-Fuel Injection | 1 |
2w3230 Lines Gp-Fuel Injection
| 2W***30 | Lines Group-Fuel Injection | 1 |
7c5552 Lines Gp-Fuel Injection
| 7C***52 | Lines Group-Fuel Injection | 1 |
7c5553 Lines Gp-Fuel Injection
| 7C***53 | Lines Group-Fuel Injection | 1 |
1w6539 Pump Gp-Fuel Injection
| 1W***39 | Pump Group-Fuel Injection | 1 |
2w0256 Pump Gp-Fuel Injection
| 2W***56 | Pump Group-Fuel Injection | 1 |
7c4992 Pump Gp-Fuel Priming & Secondary Filter
| 7C***92 | Pump Group-Fuel Prime & Sec Filter; Fuel Priming Pump And Secondary Filter Group | 1 |
1w1695 Pump Gp-Fuel Transfer
| 1W***95 | Pump Group-Fuel Transfer | 1 |
2w4160 Pump Gp-Mounting & Fuel Transfer
| 2W***60 | Pump Group-Fuel Transfer & Mtg; Fuel Transfer Pump And Mounting Group | 1 |
Intake And Exhaust System
1w6592 Compressor Gp-Air
| 1W***92 | Air Compressor Group | 1 |
7c4804 Compressor Gp
| 7C***04 | Air Compressor Group | 1 |
7c7596 Cartridge Gp
| 7C***96 | Cartridge Group-Turbocharger | 1 |
2w5397 Lines Gp-Air
| 2W***97 | Lines Group-Air; Air Lines Group | 1 |
7c4784 Lines Gp-Air
| 7C***84 | Lines Group-Air; Air Lines Group | 1 |
7c6512 Lines Gp-Compressor
| 7C***12 | Lines Group-Air Compressor | 1 |
9n5257 Lines Gp-Turbocharger Oil
| 9N***57 | Lines Group-Turbocharger Oil; Turbocharger Oil Lines Group | 1 |
9l5805 Manifold Gp-Exhaust
| 9L***05 | Manifold Group-Exhaust | 1 |
7w5785 Turbocharger Gp
| 7W***85 | Turbocharger Group; Turbocharger Group | 1 |
7c7579 Turbocharger Gp
| 7C***79 | Turbocharger Group | 1 |
Lubrication System
1p4244 Breather Gp-Crankcase
| 1P***44 | Breather Group | 1 |
2p6855 Filler Gp-Engine Oil
| 2P***55 | Filler Group-Oil | 1 |
2w2428 Gauge Gp-Oil Level
| 2W***28 | Gauge Group-Oil Level (Dipstick) | 1 |
2p6105 Lines Gp-Engine Oil
| 2P***05 | Lines Group-Engine Oil; Engine Oil Lines Group | 1 |
6n2642 Pump Gp-Engine Oil
| 0S***90 | Bolt; (3/8-16x2in)(Clip Thru Spacer To Bracket As) | 1 |
| 1P***46 | Washer-Hard; (10.2x35x6-mm Thk) | 1 |
| 4W***48 | Pump Group-Engine Oil; Pump Gp-Engine Oil Gear | 1 |
2p1784 Pump Gp-Engine Oil
| 2P***84 | Pump Group-Engine Oil; Engine Oil Pump Group | 1 |
4w2448 Pump Gp-Engine Oil*R
| 4W***48 | Pump Group-Engine Oil; Pump Gp-Engine Oil Gear | 1 |
Starting And Electrical System
7n9720 Alternator Gp
| 7N***20 | Alternator Group; Alternator Group (Robert Bosch) | 1 |
6n9294 Alternator Gp*R
| 3T***52 | Alternator Group-Charging | 0 |
| 6N***94 | Alternator Group; (24-Volt, 35-Ampere) | 1 |
| 7N***20 | Alternator Group; Alternator Group (Robert Bosch) | 0 |
3t6352 Alternator Gp-Part 2 Of 2
| 3T***52 | Alternator Group-Charging | 1 |
9g4574 Alternator Gp
| 9G***74 | Alternator Group-Charging; Alternator Group (Nippondenso) | 1 |
3t6352 Alternator Gp-Part 1 Of 2
| 3T***52 | Alternator Group-Charging | 1 |
7n6224 Alternator Gp
| 7N***24 | Alternator Group-Charging | 1 |
7c6550 Sender Gp
| 00***33 | Tee-Pipe | 1 |
| 3B***55 | Bushing To Delivery Ports | 1 |
| 6N***26 | Sender (Coolant Temperature & Transmision Oil Temperature) | 1 |
8c3651 Starting Motor Gp-Electric
| 8C***51 | Starting Motor Group-Electric; Starting Motor Gp-Electric-Delco-Remy | 1 |
4n3181 Starting Motor Gp-Electric *R
| 3T***05 | Starting Motor Group-Electric; Starting Motor Group (Robert Bosch) | 0 |
| 4N***81 | Starting Motor Group-Electric | 1 |
| 8C***51 | Starting Motor Group-Electric; Starting Motor Gp-Electric-Delco-Remy | 0 |
3t6305 Starting Motor Gp-Electric
| 3T***05 | Starting Motor Group-Electric; Starting Motor Group (Robert Bosch) | 1 |
7s3622 Starting Motor Gp-Electric
| 7S***22 | Starting Motor Group-Electric; Electric Starting Motor Group | 1 |
7c6551 Switch Gp-Remote
| 1H***44 | Lockwasher (Bracket To Cab) | 4 |
| 2H***07 | Circuit Breaker As; (40-Ampere)(Alternator) | 1 |
| 3B***01 | Lockwasher (Part Of 3f***99 Switch) | 2 |
9g7641 Switch Gp
| 9G***41 | Switch Group-Start; -Engine, Key-Vims Service | 1 |
EL300 serial number reference
The PIN plate sits on the right side of the cab exterior, below the window. Older units often carry a second plate inside the cab near the operator's seat or right foot area. The prefix is the first three characters of the PIN and identifies the model and build series; the digits that follow are the machine's sequential unit number within that prefix. Early-production units (2CF prefix) may carry either an E300 or EL300 nameplate under the same serial range — check the full PIN and dealer records to confirm which build series applies.
| Prefix | Identifies | Notes |
|---|---|---|
| 2CF | Early-production EL300 hydraulic excavator (serial range shared with companion E300 nameplate) | Covers 2CF00001 and up. Caterpillar's own service documentation lists this range jointly as "E300, EL300 hydraulic excavators," powered by the 3306 engine, meaning machines in this early serial run could carry either the E300 or EL300 nameplate. Treat as the earlier build series, ahead of the dedicated EL300-only 4NF prefix. Confirm which nameplate applies using the full PIN and dealer records. |
| 4NF | Base EL300 hydraulic excavator, dedicated EL300-only production | Covers 4NF00001 and up. This is the later, EL300-exclusive prefix (no longer shared with E300 naming). Fitted with the Cat 3306 diesel engine; exact aspiration/injection configuration (naturally aspirated vs turbocharged) is not documented for this range in available sources — confirm with dealer using the full PIN. Sale listings and parts documentation place EL300 production generally across the late 1980s into the early 1990s; treat exact year as approximate. |
Frequently asked questions
What engine does the Caterpillar EL300 use?
A Cat 3306 inline-6, 10.5-liter, direct-injection, turbocharged diesel, mechanically governed with no ECM. Output is approximately 140 kW (187 hp) flywheel, though published figures vary by source and configuration.
What is the operating weight of the Caterpillar EL300?
Approximately 31,615 kg (69,700 lb), varying with undercarriage gauge and boom/stick configuration.
What replaced the Caterpillar EL300?
There is no direct same-name successor. The EL300B is a separate, heavier machine on its own serial prefix, not a running change of the EL300. More broadly, Caterpillar phased out the E/EL alphanumeric naming in the mid-1990s in favor of the modern digit-only 300-series excavator lineup.
What EL300 owners discuss
What's the most common hydraulics complaint owners report on the EL300?
Loss of pressure, jerky boom/stick movement, and overheated oil, usually traced to worn or contaminated hydraulic pumps rather than the main control valve. Cutting open a recently pulled hydraulic filter and checking for metal debris is a quick first diagnostic before condemning the pump. If pressure loss returns soon after a filter change, that points to internal pump wear. Have your dealer verify pump condition before committing to a rebuild.
Which engine does the EL300 actually run, and does it affect parts sourcing?
The EL300 runs a Cat 3306 direct-injection turbocharged inline-6, built during the Cat-Mitsubishi joint venture era in Akashi, Japan. Confirm the engine plate and full serial before ordering parts, since exact aspiration and injection-pump fitment can vary across this machine's production run.
Any known cold-start quirks on this generation of 3306?
Pre-chamber 3306s of this vintage are known to be stubborn on the first cold start of the day, especially with tired glow plugs. Pull and bench-test each plug individually on a battery cart rather than assuming a whole set is bad; a good plug will glow and warm quickly. Flooring the throttle while cranking, then easing off once it fires, is a trick long-time operators use. Never spray ether into the intake on a glow-plug engine - it can snap the plug tips loose, drop debris into the cylinder, and damage the piston or head. Have your dealer verify glow plug and pre-chamber condition rather than relying on starting fluid as a workaround.
What undercarriage wear pattern should I expect on the EL300?
Like other Cat excavators in this weight class, EL300 final drives are prone to face-seal failure at the sprocket-to-motor interface once undercarriage debris packs in tight around the housing. Cleaning tracks and sprockets at the end of each shift measurably extends seal life. Track tension should be checked on a regular interval; over-tight tracks accelerate pin, bushing, and roller wear independent of total hours.
What electrical issues show up on a machine this old?
This is a pre-electronic, mechanically injected machine with no ECM or fault-code system to chase. Reported electrical complaints are basic: weak charging output, corroded or loose connections at the starter and gauge cluster, and age-hardened wiring insulation cracking along harness runs near the engine. Cleaning and re-terminating connections resolves most no-start or erratic-gauge complaints before anyone needs to bench-test the alternator.
Besides starting trouble, what else commonly fails on the 3306 in these machines?
Water pump failure is a recurring pattern problem on this engine family. Weep-hole seepage is the early warning sign; in worse cases the pump gears shear off the shaft and coolant temperature spikes immediately. Watch for coolant loss or coolant showing up in the engine oil, either of which points to the pump or a failing head gasket. Cracked cylinder heads and leaking pre-chambers are also called out by long-time operators as age-related faults worth checking on any high-hour example. Have your dealer verify cooling system integrity before returning an overheated unit to service.
What should I check before buying a used EL300?
Confirm the serial/product ID plate matches the paperwork - EL300 machines from this production run carry the 4NF prefix - and pin down actual hours and maintenance history rather than trusting the hour meter alone. Inspect welds at the boom-to-stick and stick-to-bucket pivots for crack lines or rust bleed, a sign of prior structural repair. Raise the machine and check tracks, rollers, idlers, and sprockets for wear, and look at the final drive housings for seal weep. Pull the hydraulic filter and check for metal, get an oil sample tested if records allow, and check whether the water pump is already seeping at the weep hole. Given the age of these machines, budget for wiring and connector cleanup regardless of what the seller claims about condition.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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