Caterpillarengine - trucktruck engine
Caterpillar C-18
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar C-18 is a heavy-duty industrial diesel engine, not a mainstream on-highway semi-tractor engine. It is an 18.1 L (1,106 cu in) turbocharged, aftercooled inline-6 with a 145 mm (5.7 in) bore and 183 mm (7.2 in) stroke, offered across ratings from roughly 429-597 kW (575-800 hp) depending on application and governed speed. Dry weight runs roughly 1,270-1,790 kg (2,800-3,945 lb), varying with manifold type, aftertreatment, and accessory drives. Caterpillar has built the C-18 since the early 2000s, spanning mechanical and ACERT electronic fuel-system generations through U.S. EPA Tier 2 to Tier 4 Final and EU Stage IV, and the platform remains in current production for well-service, land-drilling, generator-set, fire-pump, marine, and off-highway truck ratings. Truck-side, the C-18 powers vocational and severe-duty applications: off-highway articulated haul trucks, oilfield well-service and pump-drive trucks, and fire-apparatus pump engines, not everyday highway tractors. Configurations span dry-manifold and water-cooled/SCAC-manifold builds, mechanical and electronic fuel injection, and single- or multi-turbo arrangements matched to the rating.
Across its life the C-18 moved from mechanically governed, HEUI-injected ratings to ACERT-controlled Tier 3 and Tier 4 Final/Stage IV ratings, with exhaust aftertreatment added on the higher-output configurations. It succeeded the mechanical 3408 V8 in the same 18.1 L industrial displacement class as Caterpillar shifted its industrial and vocational engine lineup to the C-series platform; higher-output well-service and generator work now typically steps up to the C27 or C32 ACERT rather than a direct one-for-one C-18 replacement. Because the C-18 is a bare engine shared across haul trucks, well-service rigs, generator sets, fire pumps, and marine vessels, the used and parts market values it for block, head, and injection-system commonality: a rebuilt long block can be recalibrated to a different horsepower rating for its next application. High-hour pulls from oilfield and generator duty are common on the secondary market, so check hour meter, oil-analysis history, and turbocharger/aftercooler condition rather than relying on the nameplate rating alone.
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 C-18 specifications
Engine
| Engine family | Cat C18 diesel engine (C18 ACERT designation on later emissions-certified ratings), inline-6, 4-stroke-cycle |
| Displacement | 18.1 L (1,104.5 in³) |
| Bore x stroke | 145 mm x 183 mm (5.71 in x 7.2 in) |
| Compression ratio | 16.0:1 |
| Cylinders | 6, vertical in-line |
| Aspiration | Turbocharged and aftercooled; single-turbo on lower/mid ratings, series twin-turbocharged aftercooled (TTA) on the top-end ratings |
| Fuel system | Mechanical/electronic unit injection (MEUI); ACERT combustion technology on emissions-certified builds |
| Gross power range | 429-597 kW (575-800 hp) at 1,800-2,100 rpm, rating dependent; the 563-597 kW (755-800 hp) ratings use series twin-turbo aftercooling at 1,800 rpm |
| Peak torque | 3,655-3,710 Nm (2,696-2,736 lb-ft) at 1,300 rpm, varies slightly by rating |
| Emissions tier | Spans non-regulated/Tier 2-equivalent through Tier 3, Tier 4 Interim/Stage IIIB, and Tier 4 Final/Stage IV-V, depending on power rating and build year — confirm against the specific rating plate |
| Aftertreatment | None on lower/older ratings; diesel oxidation catalyst (DOC) alone on higher-power series-turbo ratings; DOC+DPF+SCR on the most stringent Tier 4 Final/Stage V ratings |
| Governor | Electronic (ADEM) governor |
| Rotation | Counterclockwise viewed from the flywheel end (standard) |
Weights
| Net dry weight (standard industrial rating) | 1,270-1,717 kg (2,800-3,785 lb), varies by manifold and accessory configuration |
| Dry weight (high-output twin-turbo build) | approx. 1,757 kg (3,875 lb) |
| Wet weight (high-output twin-turbo build, with oil and coolant) | approx. 1,789 kg (3,945 lb) |
| Ground pressure | Not applicable — bare power unit, not a mobile machine |
Dimensions
| Length | 1,388-1,414 mm (54.6-55.7 in) on standard-rating builds; up to 1,549 mm (61 in) on high-output twin-turbo builds |
| Width | 921-974 mm (36.3-38.3 in) on standard-rating builds; up to 1,143 mm (45 in) on high-output twin-turbo builds |
| Height | 1,243-1,257 mm (48.9-49.5 in) on standard-rating builds; up to 1,346 mm (53 in) on high-output twin-turbo builds |
| Flywheel housing | SAE No. 0 or SAE No. 1, selected per driven-equipment requirement |
| Wheelbase / track gauge / ground clearance | Not applicable — bare engine has no chassis footprint; these are set by the truck or skid it is mounted on |
Performance
| Rated speed range | 1,800-2,100 rpm, depending on power rating |
| Peak torque speed | 1,300 rpm |
| Standard altitude capability | Full rated power to 300 m (984 ft) altitude on standard ratings; derating applies above that — consult the specific rating sheet |
| Full-load fuel consumption | Approx. 123-176 L/hr (32-46 gal/hr) at 100% load, varies widely with power rating |
| Application role | Used as a truck-mounted power unit for vocational and oilfield service builds: pump and well-service skids, drilling support, and similar duty rather than sold as an on-highway line-haul drivetrain offering |
Service capacities (summary)
| Engine oil (crankcase) capacity | Approx. 34-49 L (9-13 gal) refill on standard-sump ratings; extended-capacity sump options run up to approx. 74 L (19.5 gal) on some ratings |
| Cooling system capacity (engine only) | Approx. 27-50 L (7-13.2 gal), varies by radiator/aftercooler configuration; total system volume is set by the driven-equipment cooling package |
| Fuel tank | Not applicable — bare engine has no integral fuel tank; fuel is supplied from the host truck or skid tank through 3-stage filtration (primary, secondary, tertiary) |
| Oil and filter change interval | Every 500 hours or 12 months, whichever comes first, on a typical service schedule |
| Coolant change interval | Every 3,000 hours or 5 years, whichever comes first, with extended-life coolant |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
C-18 fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | 34-41 L (9-11 US gal), roughly 36-43 US qt; varies by sump configuration (standard front or rear sump vs high-capacity center sump) | Cat DEO SAE 15W-40 diesel engine oil meeting Cat ECF-2 (pre-2007, non-DPF engines) or Cat DEO-ULS / DEO-ULS SYN meeting Cat ECF-3 (2007-and-later DPF-equipped engines); API CI-4+/CJ-4/CK-4 grade. Viscosity by climate: 15W-40 for ambient -15C to 50C (5F to 122F); 10W-30 for -20C to 40C (-4F to 104F); Cat DEO SYN 5W-40 or Cat DEO Cold Weather 0W-40 for cold-start service below -20C (-4F). |
| Cooling system | 45-50 L (12-13 US gal) on a standard radiator/aftercooler setup; other rating and pan configurations range roughly 27-68 L - varies by configuration/series, confirm against the arrangement's own coolant fill line | Cat ELC (Extended Life Coolant), factory pre-mixed 50/50 ethylene glycol and water, meeting Cat EC-1. Full service life about 12,000 hours or 6 years (roughly 1,000,000 km on-highway), with ELC Extender added at half-life. Conventional Cat DEAC antifreeze/coolant is the alternate, but needs supplemental coolant additive (SCA) checks and topped up on a fixed interval. |
| Fuel | No fuel tank on the bare engine - tank sizing is a chassis/body-builder item set by the truck spec, not covered by the engine's own maintenance manual | Ultra-low-sulfur diesel (ULSD) meeting ASTM D975 or EN 590, minimum cetane number 40 (45 recommended in cold climates). Biodiesel blends up to B20 are permitted only when the blend stock itself meets ASTM D6751 or EN 14214. |
| Transmission, final drives, hydraulic system, axles/differentials | Not applicable | Not applicable - the C-18 is supplied as a bare truck engine. Driveline, hydraulic, and axle components belong to the truck chassis and are covered by the truck manufacturer's own service literature, not the Cat engine operation and maintenance manual. |
| Grease (external points - fan hub, idler pulleys, mounts) | Spec only, no fluid volume; serviced per grease-fitting interval on the maintenance schedule | Cat Multipurpose Grease, NLGI Grade 2, lithium-complex base. Cat Prime Extreme or Cat Ultra 5-Moly (molybdenum-disulfide-fortified) grease recommended for heavier-load pivot points where called out. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar C-18 maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 3,000 h |
|
| Every 10,000 h |
|
Servicing the C-18 beyond the schedule
Predictive Maintenance & Fluid Analysis
Run S·O·S oil samples every 250 hours to catch bearing and injector wear before it reaches the fuel system's HEUI or electronic unit injectors. Pull Level 1 coolant samples at 500 hours and Level 2 samples yearly to track SCA or ELC depletion in the wet-liner cylinder block. Watch turbocharger boost and aftercooler differential-pressure trends on ACERT-equipped ratings. A slow boost drop often flags aftercooler fouling before it costs power on well-service or fire-pump duty cycles.
Corrective & Common Repairs
Common C-18 repairs center on turbocharger shaft seals, electronic unit injectors, and the water temperature regulator housing, all called out by name in the factory schedule. Aftercooler core leaks show up as coolant loss or power loss under load and are common on high-hour well-service and fire-pump units run at sustained full rating. Crankshaft vibration damper failure is a known wear point on high-hour blocks; inspect for bulging or fluid leakage before it damages the front gear train.
Overhaul & Rebuild Points
Top-end overhaul work centers on the cylinder head, valve train, and unit injectors, with valve lash and injector timing reset during any major service. Because the C-18 uses a wet-liner block shared across industrial, marine, well-service, and generator ratings, liner and main-bearing wear tracks duty cycle far more than calendar age. Rebuilders reset the ECM calibration to the intended horsepower rating during reassembly, since one long block supports ratings from roughly 429 to 597 kW depending on the application it returns to.
Seasonal & Environment Servicing
Cold-climate C-18 installations need the correct glycol blend and a working ether or intake-air starting aid checked before winter; battery and cable condition matter more at low temperature given the engine's compression-ignition start load. In dusty oilfield or fireground environments, service the air cleaner element by indicator reading rather than a fixed interval, and clean the aftercooler and radiator fin pack more often than the factory 250-hour baseline. Drain fuel-tank water and sediment daily in humid or high-condensation storage.
C-18 common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 161-1705 | Sensor As-Pressure | Lubrication service | Check fitment → |
| 1R-0716 | Filter As-Engine Oil | Lubrication service | Check fitment → |
| 8T-6765 | Plug-Pipe | Scheduled service item | Check fitment → |
| 9S-8752 | Nut-Full | Scheduled service item | Check fitment → |
| 136-3742 | Filter-Water Pump | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
C-18 fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| CID 1-6, FMI 5/6 (Flash Code 111-116) | ECM detects injector solenoid current for one cylinder below or above the expected normal range. | Damaged or corroded injector wiring/connector, failed injector solenoid, or an intermittent ECM driver. | Inspect the injector harness and connector for that cylinder for chafing or corrosion, run the injector solenoid test in Cat ET, and swap the injector to another cylinder to isolate injector vs. wiring before replacing parts. |
| CID 100 - FMI 1 (Flash Code 157) | Engine oil pressure has dropped below the minimum allowed for current engine speed - the most severe oil pressure event. | Low oil level, worn oil pump, clogged oil filter, or excessive bearing clearance. | Shut down and check oil level and condition immediately, confirm actual pressure with a manual gauge before trusting the sensor, replace the filter and recheck. |
| CID 100 - FMI 3/4 (Flash Code 152) | Oil pressure sensor signal voltage is outside the normal range - an electrical fault, not necessarily a real pressure loss. | Open or shorted sensor wiring, corroded connector, or a failed sensor. | Check the sensor connector and harness condition, verify sensor supply and signal voltage against spec, replace the sensor if wiring tests good. |
| CID 110 - FMI 15/16 (Flash Code 168) | Engine coolant temperature has risen above the normal operating range. | Low coolant level, stuck thermostat, blocked or dirty radiator, weak water pump, or an inoperative fan clutch. | Check coolant level and look for leaks, verify fan clutch and thermostat operation, clean the radiator core before condemning the sensor. |
| CID 110 - FMI 3/4 (Flash Code 133) | Coolant temperature sensor signal voltage is out of the normal range. | Damaged sensor wiring, corroded connector, or a failed sensor. | Inspect wiring and connector, test sensor resistance against spec, replace the sensor if the circuit checks good. |
| SPN 637 - FMI 13 (CID 261-13, Flash Code 143) | Engine speed/timing sensor signal is missing, erratic, or has not been calibrated to the ECM after a sensor or timing-related repair. | Timing sensor not recalibrated after replacement, damaged or metal-contaminated sensor tip, or a harness fault. | Inspect the timing sensor for damage or metal debris on the tip, check harness continuity, and run the engine speed/timing sensor calibration procedure in Cat ET after any related repair. |
| CID 190 - FMI 0 (Flash Code 141) | Engine speed exceeded the maximum allowable rpm - the most severe overspeed event. | Downhill overrun without engine braking, a driveline or transmission fault forcing the engine over speed, or a throttle/governor malfunction. | Review logged event data in Cat ET for rpm and duration, check engine brake operation, and inspect the driveline for a fault that could over-drive the engine. |
| CID 168 - FMI 2/3/4 (Flash Code 422) | ECM battery supply voltage is erratic or outside the normal range. | Loose or corroded battery terminals, a weak or failing alternator, a bad chassis ground, or damaged wiring to the ECM. | Clean and tighten battery and ground connections, load-test the charging system, and check ECM power and ground circuits for corrosion. |
| SPN 5584 - FMI 0 (Fuel Filter Restriction - High) | Differential pressure across the fuel filter indicates restricted fuel flow. | Dirty or clogged fuel filter element, water or contamination in the fuel, or a collapsed filter. | Replace primary and secondary fuel filters, drain the water separator, and check for a restriction further upstream in the fuel supply. |
| SPN 2791 - FMI 5/6 (EGR Valve Control) | ECM detects abnormal current in the EGR valve actuator circuit. | EGR valve sticking or seized from carbon buildup, damaged actuator wiring, or a failed valve actuator. | Remove and inspect the EGR valve for carbon buildup and free movement, check actuator wiring, clean or replace the valve as needed. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
C-18 attachments & work tools
Work tools / attachments
The C-18 is a bare diesel engine block, not a machine with ground-engaging tools. It has no buckets, blades, forks, rippers, or quick-coupler work-tool line the way an excavator or loader does. The genuine "options" for this engine are arrangement and configuration choices, not work tools.
Host application
The C-18/C18 18.1 L inline-six is an off-highway engine, used as the haul-truck powerplant in Caterpillar's own surface-mining and quarry rigid trucks in the roughly 50-ton payload class (772-family), plus shared industrial power-unit, generator-set, and marine auxiliary variants built on the same block. It was never factory-offered as an on-highway semi-truck engine.
Power rating range
Across the full C18 platform, factory ratings span roughly 400-600 kW (550-800 hp), varying by generation (pre-emissions mechanical vs ACERT electronic) and market/tier. In the haul-truck application the rating sits near 410-451 kW (550-605 hp) net/gross at 1800 rpm; exact figure varies by configuration/series.
Turbocharging arrangement
Offered as either a single turbocharged-aftercooled (TA) setup or a series twin-turbocharged-aftercooled (TTA) setup depending on the power class ordered. Higher-output ratings toward the top of the range use the twin-turbo arrangement; lower ratings use the single-turbo build.
Governor / electronic control
Earlier builds used mechanical or basic electronic unit-injection governing; later ACERT-era engines use Caterpillar's ADEM electronic control module, with governing class matched to the driven equipment (for example, ISO8528-5 governing classes on generator-set calibrations). Mobile/truck calibrations differ from genset and marine calibrations on the same base engine.
PTO (power take-off) provisions
On industrial power-unit variants, rear PTO is available through an SAE No. 0 or SAE No. 1 flywheel housing with optional SAE A, SAE B, or SAE C drive pads, and dual rear PTO is offered on higher-rated builds; a front-of-engine power take-off is also a factory option. These PTO options apply to industrial/pump-drive builds, not the haul-truck installation, which drives the truck's own hydraulic and drivetrain systems directly.
Flywheel housing / mounting
SAE No. 0 or SAE No. 1 flywheel housings are offered depending on rating and driven equipment, which sets the bell-housing and coupling hardware that mates to the engine. Mounting footprint and flywheel choice are matched to the host machine rather than being a user-selectable haul-truck option.
Cooling system configuration
The mobile/truck build uses jacket-water cooling with air-to-air aftercooling (ATAAC) through the host machine's own radiator package. Stationary and marine variants of the same block instead offer heat-exchanger or keel-cooled circuits with separate-circuit aftercooling (SCAC); cooling arrangement follows the application, not a haul-truck order option.
Emissions / aftertreatment configuration
The C18 family spans mechanically governed pre-emissions builds through ACERT electronic builds meeting Tier 3 and Tier 4 Final/Stage V, with aftertreatment ranging from no exhaust treatment on older/lower-tier builds up to DOC+DPF+SCR on the cleanest ratings. Off-highway mining-truck ratings commonly run at lower, non-DEF tiers suited to unregulated or Tier 2-equivalent markets; exact aftertreatment varies by series and market/regulatory tier.
All C-18 assemblies by section
Every catalogued assembly group for the Caterpillar C-18. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Air Inlet And Exhaust System
179-1482 Elbow Gp-Air Inlet
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 3 |
| 17***72 | Elbow | 1 |
| 17***82 | Elbow Group-Air Inlet | 1 |
109-4202 Elbow Gp-Air Inlet
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 4 |
| 10***25 | Gasket; (Air Inlet Manifold)(Intake Manifold Inlet) | 1 |
| 10***02 | Elbow Group-Air Inlet | 1 |
114-1906 Lines Gp-Air
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 2 |
| 11***06 | Lines Group-Air | 1 |
| 5H***04 | Packing,Preformed Elbow Part Of Kit P/N 5r***26 | 2 |
114-1904 Lines Gp-Air
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 2 |
| 11***04 | Lines Group-Air | 1 |
| 5M***94 | Washer; Bracket To Tee, Bracket To Block, Tube As. To Tee, Tube As. To Oil Cooler | 2 |
135-6552 Manifold Gp-Exhaust
| 10***54 | Manifold-Exhaust; (Center) | 1 |
| 10***08 | Manifold-Exhaust; (End)(End) | 2 |
| 10***92 | Stud-Taperlock; (3/8-16x3.93in) | 11 |
183-1199 Turbocharger Gp
| 18***99 | Turbocharger Group | 1 |
| 18***29 | Housing-Turbine | 1 |
| 18***32 | Cartridge Group-Turbocharger | 1 |
183-7974 Turbocharger Gp
| 18***99 | Turbocharger Group | 1 |
| 18***74 | Turbocharger Group | 1 |
| 1S***95 | Gasket-Turbocharger To Manifold; Gasket Turbocharger To Manifold | 1 |
Basic Engine
133-9907 Adapter Gp-Pump Drive
| 13***06 | Adapter | 1 |
| 13***07 | Adapter Group-Pump Drive; -Remote | 1 |
| 1B***67 | Ball Bearing | 2 |
232-5187 Air Compressor Gp
| 03***43 | Adapter - 45 Degrees - 8 Valve Ports P, T, C1, C2 | 1 |
| 03***46 | Elbow, 90 Deg Adj., 1/4in. J.I.C. X 7/16in.-14 Str. Thd. | 1 |
| 11***28 | Elbow; (90-Deg) | 1 |
304-2693 Air Compressor Gp
| 09***74 | Bolt-Socket Head; (M5x0.8x12-mm) | 4 |
| 22***22 | Valve As-Pressure Relief; (Air Compressor) | 1 |
| 26***22 | Kit-Unloader; (Air Compressor) | 2 |
172-4307 Air Compressor Gp
| 17***50 | Tube As; (Coolant Return) | 1 |
| 17***06 | Air Compressor Group | 1 |
| 17***07 | Air Compressor Group | 1 |
175-6779 Air Compressor Gp
| 09***57 | Screw-Machine; (M6x1x8.6-mm) | 8 |
| 09***12 | Seal-O-Ring (Id=89.40mm) | 1 |
| 17***66 | Valve As-Pressure Relief; (Air Compressor) | 1 |
238-4508 Air Compressor Gp
| 03***46 | Elbow, 90 Deg Adj., 1/4in. J.I.C. X 7/16in.-14 Str. Thd. | 1 |
| 11***28 | Elbow; (90-Deg) | 1 |
| 17***50 | Tube As; (Coolant Return) | 1 |
172-4306 Air Compressor Gp
| 11***28 | Elbow; (90-Deg) | 1 |
| 14***42 | Seal-Integral; (Auxiliary Sea Water Pump) | 1 |
| 15***35 | Gear; (40-Teeth) | 1 |
122-1248 Base Gp-Valve Cover & Inj Harn
| 06***91 | Terminal-Blade; (14-Ga To 18-Ga) | 6 |
| 10***01 | Kit; (Receptacle) (12-Pin) (Includes Receptacle As & Wedge) | 1 |
| 10***34 | Kit-Receptacle; (12-Pin)(Valve Cover & Inj Harness) | 1 |
130-9710 Camshaft Gp
| 10***89 | Cover | 1 |
| 11***36 | Screw-Flat Head; (5/16-18x0.875-In) | 3 |
| 13***10 | Camshaft Group | 1 |
107-6736 Cover Gp-Cylinder Block
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 2 |
| 10***36 | Cover Group-Cylinder Block; -Remote | 1 |
| 4N***99 | Gasket; (Oil Drain) | 1 |
140-9746 Cover Gp-Cylinder Block
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 4 |
| 12***35 | Seal-Integral | 1 |
| 14***46 | Cover Group-Cylinder Block; (Central Structure) | 1 |
107-6737 Cover Gp-Cylinder Block
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 2 |
| 10***37 | Cover Group-Cylinder Block; -Remote | 1 |
| 4N***99 | Gasket; (Oil Drain) | 1 |
9n-3889 Cover Gp-Flywheel Housing
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 1 |
| 0S***19 | Bolt,Machine Gear Retaining Part Of Kit P/N 1w***46 | 1 |
| 23***37 | Seal-Integral | 1 |
159-6159 Cover Gp-Front Housing
| 03***55 | Locknut; (5/16-18-Thd)(Marked X) | 2 |
| 15***59 | Cover Group-Front Housing | 1 |
| 16***71 | Seal | 1 |
159-9340 Cover Gp-Valve Mechanism
| 15***41 | Cover Group-Valve Mechanism | 1 |
| 15***42 | Cover Group-Valve Mechanism | 1 |
| 15***40 | Cover Group-Valve Mechanism | 1 |
341-6804 Cover Gp-Valve Mechanism
| 14***78 | Grommet | 1 |
| 23***06 | Cover As-Valve | 1 |
| 24***37 | Seal; (Cover, Valve Mechanism) | 1 |
150-3141 Cover Gp-Valve Mechanism
| 14***76 | Cover-Valve Mechanism | 1 |
| 14***78 | Grommet | 1 |
| 15***41 | Cover Group-Valve Mechanism | 1 |
150-3135 Cover Gp-Valve Mechanism
| 14***78 | Grommet | 1 |
| 15***57 | Cover-Valve Mech | 1 |
| 15***35 | Cover Group-Valve Mechanism | 1 |
239-5820 Cover Gp-Valve Mechanism
| 15***35 | Cover Group-Valve Mechanism | 1 |
| 15***39 | Cover Group-Valve Mechanism | 1 |
| 23***20 | Cover Group-Valve Mechanism | 1 |
159-9339 Cover Gp-Valve Mechanism
| 15***41 | Cover Group-Valve Mechanism | 2 |
| 15***39 | Cover Group-Valve Mechanism | 1 |
| 15***43 | Cover Group-Valve Mechanism | 1 |
150-3139 Cover Gp-Valve Mechanism
| 14***78 | Grommet | 1 |
| 15***36 | Cover As-Valve Mechanism | 1 |
| 15***39 | Cover Group-Valve Mechanism | 1 |
159-9343 Cover Gp-Valve Mechanism
| 14***78 | Grommet | 1 |
| 15***43 | Cover Group-Valve Mechanism | 1 |
| 17***39 | Cover As-Valve; (Breather) | 1 |
150-3142 Cover Gp-Valve Mechanism
| 11***53 | Cap As-Filler; (Engine Oil) | 1 |
| 14***78 | Grommet | 1 |
| 15***38 | Cover As-Valve Mechanism | 1 |
189-4917 Crankshaft Gp
| 18***81 | Gear-Crankshaft; (80-Teeth) | 1 |
| 18***17 | Crankshaft Group | 1 |
| 18***18 | Crankshaft As | 1 |
323-8451 Cylinder Block As
| 15***09 | Seal-Liner | 6 |
| 15***93 | Seal-Liner | 12 |
| 26***31 | Cylinder Block As | 1 |
175-9086 Cylinder Block As
| 15***09 | Seal-Liner | 6 |
| 15***10 | Seal-Liner | 6 |
| 15***93 | Seal-Liner | 6 |
267-4631 Cylinder Block As
| 16***81 | Cap-Crankshaft Bearing | 7 |
| 26***31 | Cylinder Block As | 1 |
| 3P***23 | Bolt-Bearing Cap; (7/8-14x7.75-In) | 14 |
201-0568 Cylinder Block Gp
| 10***99 | Plug | 2 |
| 14***29 | Seal; (Drainback) | 1 |
| 17***86 | Cylinder Block As | 1 |
261-0191 Cylinder Block Gp
| 10***99 | Plug | 2 |
| 14***29 | Seal; (Drainback) | 1 |
| 1S***40 | Dowel; (30.23 mm X 9.37 mm) | 1 |
245-4324 Cylinder Head As
| 12***47 | Guide-Valve; (0.51-mm Os)(Standard) | 0 |
| 12***75 | Guide-Valve; (Standard) | 24 |
| 12***12 | Guide-Valve; (0.13-mm Os)(Standard) | 0 |
281-1640 Cylinder Head As
| 12***47 | Guide-Valve; (0.51-mm Os)(Standard) | 0 |
| 12***75 | Guide-Valve; (Standard) | 24 |
| 12***12 | Guide-Valve; (0.13-mm Os)(Standard) | 0 |
217-4526 Cylinder Head Gp
| 10***73 | Fastener Group-Cylinder Head; (Marked X) | 10 |
| 12***54 | Bolt-12 Point Head; (3/4-16x8.5-In) | 1 |
| 13***11 | Sensor Group-Temperature; (Transmission Lubrication Oil) | 1 |
263-5055 Cylinder Head Gp
| 15***24 | Valve; (Exhaust) | 12 |
| 16***78 | Seal-Valve Stem; (Exhaust) | 24 |
| 18***01 | Rotocoil Assem. | 24 |
183-5296 Cylinder Head Gp
| 15***24 | Valve; (Exhaust) | 12 |
| 16***78 | Seal-Valve Stem; (Exhaust) | 24 |
| 18***96 | Cylinder Head Group | 1 |
235-3177 Cylinder Head Gp
| 12***54 | Bolt-12 Point Head; (3/4-16x8.5-In) | 10 |
| 12***55 | Bolt-12 Point Head; (3/4-16x7.638-In) | 16 |
| 19***24 | Sensor Group-Pressure; -Air Inlet Manifold | 1 |
6i-3638 Drive Gp-Pump
| 0S***90 | Bolt; (3/8-16x2in)(Clip Thru Spacer To Bracket As) | 3 |
| 13***07 | Adapter Group-Pump Drive; -Remote | 1 |
| 5M***94 | Washer; Bracket To Tee, Bracket To Block, Tube As. To Tee, Tube As. To Oil Cooler | 4 |
194-4274 Engine Brake Gp
| 14***97 | Nut; (1/2-13-Thd) | 3 |
| 16***67 | Bolt-12 Point Head; (1/2-13x146.05-mm) | 3 |
| 18***50 | Housing Group-Engine Brake | 3 |
148-7486 Engine Brake Gp
| 14***97 | Nut; (1/2-13-Thd) | 3 |
| 14***86 | Engine Brake Group | 1 |
| 16***67 | Bolt-12 Point Head; (1/2-13x146.05-mm) | 3 |
221-1196 Engine Brake Gp
| 14***97 | Nut; (1/2-13-Thd) | 3 |
| 16***67 | Bolt-12 Point Head; (1/2-13x146.05-mm) | 3 |
| 22***96 | Engine Brake Group | 1 |
102-2265 Fastener Gp-Fan Drive
| 10***65 | Fastener Group-Fan Drive | 1 |
| 11***20 | Rod As-Adjusting; (Fan Drive) | 1 |
| 5M***94 | Washer; Bracket To Tee, Bracket To Block, Tube As. To Tee, Tube As. To Oil Cooler | 1 |
108-9382 Fastener Gp-Front Housing
| 10***82 | Fastener Group-Front Housing | 1 |
| 14***68 | Stud-Taperlock | 2 |
| 1F***58 | Nut-Full; (1/2-13-Thd)(Air Lines) | 2 |
110-6984 Fastener Gp-Front Housing
| 11***84 | Fastener Group-Front Housing | 1 |
| 1A***64 | Bolt (4.75 In. Long-Location "B") | 1 |
| 5M***94 | Washer; Bracket To Tee, Bracket To Block, Tube As. To Tee, Tube As. To Oil Cooler | 1 |
4p-6846 Fastener Gp-Front Housing
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 2 |
| 4P***46 | Fastener Group-Front Housing; -Remote | 1 |
| 5M***94 | Washer; Bracket To Tee, Bracket To Block, Tube As. To Tee, Tube As. To Oil Cooler | 2 |
176-7007 Fastener Gp-Oil Pan
| 0L***70 | Bolt (2-1/4") Filler Tube Assembly To Transfer Drive Case | 24 |
| 17***07 | Fastener Group-Oil Pan | 1 |
| 24***14 | Sleeve As | 24 |
196-3796 Fitting Gp-Air Compressor
| 19***96 | Fitting Group-Air Compressor | 1 |
| 3D***24 | O-Ring - For Oil Drain & Level Plug (Items 3 & 7) | 1 |
| 5P***30 | Connector | 1 |
341-8629 Fitting Gp-Air Compressor
| 06***69 | Stem | 1 |
| 24***03 | Connector | 1 |
| 34***29 | Fitting Group-Air Compressor | 1 |
107-3847 Flywheel Gp
| 0S***76 | Bolt 5.08 cm(2 In.) Long | 12 |
| 10***47 | Flywheel Group | 1 |
| 12***57 | Flywheel As | 1 |
204-9316 Gear Gp-Camshaft
| 10***26 | Dowel | 1 |
| 20***16 | Gear Group-Camshaft | 1 |
| 9X***72 | Bolt-Locking; (3/8-16x0.875-In) | 16 |
207-0449 Gear Gp-Front
| 03***85 | Bolt-12 Point Hd-Engine Flywheel To | 6 |
| 0S***71 | Screw,Cap,Hexagon; Tube Assembly To Turbocharger And Elbow Mounting | 1 |
| 10***68 | Bearing-Sleeve | 1 |
189-5950 Housing Gp-Engine Brake
| 10***80 | Spool As-Valve | 2 |
| 14***36 | Spring; (Inner)(Control Valve) | 2 |
| 14***96 | Spring; (Outer)(Control Valve) | 2 |
221-1197 Housing Gp-Engine Brake
| 10***80 | Spool As-Valve | 2 |
| 14***36 | Spring; (Inner)(Control Valve) | 2 |
| 14***96 | Spring; (Outer)(Control Valve) | 2 |
160-6265 Housing Gp-Flywheel
| 0S***19 | Bolt,Machine Gear Retaining Part Of Kit P/N 1w***46 | 1 |
| 16***65 | Housing Group-Flywheel | 1 |
| 16***29 | Bolt; (3/8-16x1.5-In)(Marked Z) | 9 |
341-8630 Housing Gp-Front
| 06***55 | Seal-O-Ring (Id=47.22mm) | 1 |
| 0L***70 | Bolt (2-1/4") Filler Tube Assembly To Transfer Drive Case | 1 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 11 |
159-8616 Housing Gp-Front
| 06***55 | Seal-O-Ring (Id=47.22mm) | 1 |
| 0L***70 | Bolt (2-1/4") Filler Tube Assembly To Transfer Drive Case | 1 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 11 |
165-5581 Housing Gp-Front
| 0L***70 | Bolt (2-1/4") Filler Tube Assembly To Transfer Drive Case | 1 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 11 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 2 |
112-2418 Lifting Gp-Engine
| 0S***95 | Bolt 1.25 In. (31.75 mm) Long Guard Assemblies To Radiator Guard | 4 |
| 10***86 | Eye-Lifting | 1 |
| 11***18 | Lifting Group-Engine | 1 |
111-2088 Lifting Gp-Engine
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 8 |
| 10***85 | Eye-Lifting | 1 |
| 11***88 | Lifting Group-Engine; (Rear) | 1 |
111-2086 Lifting Gp-Engine
| 0S***94 | Bolt (1 In. Long 3/8 In. Dia.); Plate Assembly To Support Assembly | 8 |
| 11***26 | Eye-Lifting | 1 |
| 11***86 | Lifting Group-Engine | 1 |
148-7482 Mechanism Gp-Fuel Pump & Valve
| 14***82 | Mechanism Group-Fuel Pump & Valve | 1 |
| 19***98 | Rocker Arm Group | 3 |
| 6I***58 | Bridge-Valve | 12 |
335-4262 Pan Gp-Oil -Engine
| 0L***51 | Bolt Starting Engine Fuel Tank Bracket To Diesel Intake Manifold | 3 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 3 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 2 |
253-6181 Pan Gp-Oil -Engine
| 0L***51 | Bolt Starting Engine Fuel Tank Bracket To Diesel Intake Manifold | 3 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 3 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 2 |
213-7552 Piston & Rod Gp
| 15***25 | Bolt; (7/16-14-2a-Thd) | 1 |
| 18***50 | Pin-Piston | 1 |
| 18***03 | Ring-Piston; (Intermediate) | 1 |
308-4486 Piston & Rod Gp
| 15***25 | Bolt; (7/16-14-2a-Thd) | 1 |
| 18***50 | Pin-Piston | 1 |
| 19***29 | Jet As-Piston Cooling | 1 |
353-9979 Plate As-Front Housing
| 12***57 | Washer; (10.85x19.3x1.27-mm Thk) | 9 |
| 12***27 | Washer-Special; (Sealing)(Sealing) | 2 |
| 12***28 | Stud; (Brake) | 12 |
213-1800 Plug Gp-Cylinder Block
| 21***00 | Plug Group-Cylinder Block | 1 |
| 23***81 | Seal-O-Ring | 1 |
| 30***31 | Plug As | 1 |
229-9477 Plug Gp-Cylinder Block
| 21***66 | Seal-O-Ring; (Engine Oil) | 1 |
| 22***77 | Plug Group-Cylinder Block | 1 |
| 23***80 | Seal-O-Ring | 1 |
305-9196 Plug Gp-Cylinder Block
| 30***96 | Plug Group-Cylinder Block | 1 |
| 6V***65 | O-Ring - For Oil Fill Plug | 1 |
| 9S***10 | Plug; (Straight Thread O-Ring)(Cylinder Head) | 1 |
234-5986 Plug Gp-Cylinder Head
| 18***07 | Plug As; (Hi Tempertature) | 4 |
| 21***68 | Seal-O-Ring; (11.89-mm Id) | 1 |
| 23***86 | Plug Group-Cylinder Head | 1 |
109-4314 Plug Gp-Flywheel Housing
| 10***14 | Plug Group-Flywheel Housing | 1 |
| 7X***31 | Plug-Pipe; (Flywheel Housing Drain) | 1 |
221-1877 Pulley Gp-Crankshaft
| 10***98 | Pulley-Crankshaft; (14-Groove) | 1 |
| 15***34 | Damper As | 1 |
| 22***77 | Pulley Group-Crankshaft | 1 |
203-4691 Pulley Gp-Crankshaft
| 15***34 | Damper As | 1 |
| 20***90 | Pulley; (10-Groove)(Crankshaft) | 1 |
| 20***91 | Pulley Group-Crankshaft | 1 |
320-2796 Rocker Arm Gp -Intake
| 25***21 | Button | 1 |
| 27***91 | Screw-Arm Adjustment; (3/8-24x1.20-In) | 1 |
| 27***17 | Nut; (3/8-24-Thd) | 1 |
328-4238 Rocker Arm Gp -Exhaust
| 06***39 | Seal-O-Ring | 1 |
| 19***51 | Button; (24-mm Od) | 1 |
| 19***69 | Screw-Arm Adjustment; (9/16-18x2-In) | 1 |
278-1931 Rocker Arm Gp
| 06***39 | Seal-O-Ring | 2 |
| 19***51 | Button; (24-mm Od) | 2 |
| 19***69 | Screw-Arm Adjustment; (9/16-18x2-In) | 2 |
328-4239 Rocker Arm Gp
| 25***21 | Button | 1 |
| 27***91 | Screw-Arm Adjustment; (3/8-24x1.20-In) | 1 |
| 27***17 | Nut; (3/8-24-Thd) | 1 |
328-4237 Rocker Arm Gp
| 30***22 | Shaft As-Rocker Arm, Exhaust Manifold | 1 |
| 32***96 | Rocker Arm Group; -Intake | 2 |
| 32***37 | Rocker Arm Group | 1 |
198-9898 Rocker Arm Gp
| 03***13 | Seal-O-Ring | 2 |
| 06***39 | Seal-O-Ring | 2 |
| 19***51 | Button; (24-mm Od) | 2 |
319-7401 Seal Gp-Crankshaft -Front
| 14***67 | Seal Group-Crankshaft; (Front) | 1 |
| 31***01 | Seal Group-Crankshaft; -Front | 1 |
319-0785 Seal Gp-Crankshaft -Rear
| 14***68 | Seal-Crankshaft; (Rear)(Flywheel Housing) | 1 |
| 31***85 | Seal Group-Crankshaft; -Rear | 1 |
110-8875 Support Gp-Engine
| 11***75 | Support Group-Engine | 1 |
| 2H***88 | Bolt- 12 cm(4.75 In.) Long-Location "F" | 8 |
| 4W***76 | Support | 1 |
130-0717 Support Gp-Engine
| 13***16 | Support | 1 |
| 13***17 | Support Group-Engine | 1 |
| 2H***88 | Bolt- 12 cm(4.75 In.) Long-Location "F" | 8 |
Cooling System
109-2373 Fastener Gp-Water Pump
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 1 |
| 10***73 | Fastener Group-Water Pump; (Water Pump Cover) | 1 |
224-0875 Fitting Gp-Water Lines
| 22***75 | Fitting Group-Water Lines | 1 |
| 23***80 | Seal-O-Ring | 1 |
| 30***15 | Adapter As | 1 |
137-0272 Fitting Gp-Water Lines
| 13***72 | Fitting Group-Water Lines | 1 |
| 3R***87 | Connector-Flared | 1 |
237-5315 Lines Gp-Water -Engine Oil Cooler
| 0L***52 | Capscrew (3/8 - 16 Nc X 3 1/4 Gd8, Hex) | 2 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 4 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 3 |
190-7652 Lines Gp-Water
| 0L***52 | Capscrew (3/8 - 16 Nc X 3 1/4 Gd8, Hex) | 2 |
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 4 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 3 |
159-1599 Plug Gp-Water Lines
| 15***99 | Plug Group-Water Lines | 1 |
| 7X***32 | Plug; (Pipe) (3/8-18 Nptf Thd) | 1 |
142-0851 Plug Gp-Water Lines
| 14***51 | Plug Group-Water Lines | 1 |
| 7X***31 | Plug-Pipe; (Flywheel Housing Drain) | 3 |
| 8T***67 | Plug-Pipe; (Oil Cooler Bonnet Drain) | 1 |
174-5986 Pump Gp-Water
| 10***77 | Seal-O-Ring; (100.97mm Id) | 1 |
| 12***72 | Seal-O-Ring (215.49mm Id) | 1 |
| 16***19 | Pump Group-Water | 1 |
161-5719 Pump Gp-Water
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 1 |
| 10***30 | Bearing As-Roller | 1 |
| 12***17 | Seal Group; (Water Pump) | 1 |
Electrical And Starting System
126-7631 Connection Gp-Electrical
| 12***31 | Connection Group-Electrical; (Cylinder Block Ground) | 1 |
| 12***49 | Stud; (3/8-16, 5/8-18x3.1-In) | 1 |
| 5P***47 | Washer (Bracket To Valve Support) | 1 |
159-9107 Connection Gp-Electrical -Cylinder Head Ground
| 15***07 | Connection Group-Electrical; -Cylinder Head Ground | 1 |
| 17***99 | Stud; (3/8-16-Thd) | 1 |
| 6V***01 | Nut; (3/8-16-Thd)(Plate To Rh And Lh Bracket As) | 1 |
161-7066 Control & Mtg Gp-Engine Elek
| 13***89 | Plate Assem. | 1 |
| 15***96 | Support As | 1 |
| 15***98 | Support As | 1 |
348-2377 Control Gp-Engine Electronic
| 18***72 | Screw-Pan Head; (No 8-32x9.52-mm)(Wax Coated) | 1 |
| 2L***75 | Terminal; (14-Ga To 16-Ga, No. 8 Screw)(Relay Switch "B" & "S") | 1 |
| 2L***78 | Terminal-Ring; (14-Ga To 16-Ga, 5/16-In Screw) | 1 |
206-2701 Control Gp-Engine Electronic
| 20***01 | Control Group-Engine Electronic | 1 |
| 32***02 | Control Group-Engine Electronic | 1 |
322-3602 Control Gp-Engine Electronic
| 18***72 | Screw-Pan Head; (No 8-32x9.52-mm)(Wax Coated) | 1 |
| 32***02 | Control Group-Engine Electronic | 1 |
| 7X***15 | Strap; (Grounding) | 1 |
286-9120 Fastener Gp-Engine Wiring
| 0S***76 | Bolt 5.08 cm(2 In.) Long | 2 |
| 28***20 | Fastener Group-Engine Wiring | 1 |
| 2B***14 | Spacer; (17.4x22.2x17.5-mm Thk) | 2 |
160-6898 Sensor & Mtg Gp-Electric
| 16***98 | Sensor & Mtg Group-Electric | 1 |
| 16***03 | Sensor Group-Pressure; (Turbocharger Inlet, Rh) | 1 |
| 16***05 | Sensor As-Pressure; (Unfiltered Engine Oil) | 1 |
194-6724 Sensor Gp-Pressure
| 15***60 | Kit-Connecting Plug; (3-Pin)(Engine Sensor Wiring Harness) | 1 |
| 19***26 | Harness As-Sensor; (16-18 Ga Wire)(Engine Oil Temperature) | 3 |
| 19***24 | Sensor Group-Pressure; -Air Inlet Manifold | 1 |
197-8391 Sensor Gp-Temperature
| 13***45 | Pad; (Connector) | 1 |
| 19***91 | Sensor Group-Temperature; -Air Inlet Manifold | 1 |
| 23***80 | Seal-O-Ring | 1 |
212-2190 Wiring Gp-Electronic Control
| 0S***09 | Bolt (3/4") Filler Tube Assembly To Transfer Drive Case | 2 |
| 0S***76 | Bolt 5.08 cm(2 In.) Long | 2 |
| 0S***91 | Screw,Cap,Hexagon Bearing Retainer; Part Of Kit P/N 1w***82 | 1 |
Engine Arrangement
207-5431 Engine Ar-Complete
| 10***65 | Fastener Group-Fan Drive | 1 |
| 10***47 | Flywheel Group | 1 |
| 10***36 | Cover Group-Cylinder Block; -Remote | 1 |
330-5668 Engine Ar-Complete
| 10***47 | Flywheel Group | 1 |
| 10***36 | Cover Group-Cylinder Block; -Remote | 1 |
| 10***37 | Cover Group-Cylinder Block; -Remote | 1 |
338-5356 Engine Ar-Core
| 12***48 | Base Group-Valve Cover & Inj Harn | 1 |
| 13***10 | Camshaft Group | 1 |
| 13***89 | Pump Group-Fuel Injection | 6 |
235-3467 Engine Ar-Core
| 12***48 | Base Group-Valve Cover & Inj Harn | 1 |
| 13***10 | Camshaft Group | 1 |
| 13***89 | Pump Group-Fuel Injection | 6 |
208-5173 Engine Ar-Core
| 12***48 | Base Group-Valve Cover & Inj Harn | 1 |
| 13***10 | Camshaft Group | 1 |
| 13***89 | Pump Group-Fuel Injection | 6 |
Fuel System
159-9491 Base Gp-Fuel Filter
| 13***17 | Base As-Fuel Filter | 1 |
| 13***73 | Valve Group-Fuel Bypass; -Filter | 1 |
| 14***33 | Fitting | 1 |
170-1213 Fitting Gp-Fuel Lines
| 10***75 | Elbow; (90-Deg) | 1 |
| 17***13 | Fitting Group-Fuel Lines | 1 |
| 8L***86 | Seal-O-Ring (Id=16.36mm); (16.36-mm Id) | 1 |
109-2786 Fitting Gp-Fuel Lines
| 10***86 | Fitting Group-Fuel Lines | 1 |
| 10***69 | Elbow | 1 |
| 21***68 | Seal-O-Ring; (11.89-mm Id) | 1 |
108-8756 Fitting Gp-Fuel Lines
| 10***43 | Connector-O-Ring | 1 |
| 10***56 | Fitting Group-Fuel Lines | 1 |
| 21***68 | Seal-O-Ring; (11.89-mm Id) | 1 |
108-2312 Fitting Gp-Quick Disconnect
| 10***12 | Fitting Group-Quick Disconnect; -Fuel | 1 |
| 21***68 | Seal-O-Ring; (11.89-mm Id) | 1 |
| 6V***52 | Cap-Dust; (Fuel Supply Tee Connection) | 1 |
207-7427 Lines Gp-Fuel
| 03***47 | Elbow-Filtered Fuel From Based Assembly | 1 |
| 03***42 | Seal-O-Ring; (11.89mm Id) | 8 |
| 0S***09 | Bolt (3/4") Filler Tube Assembly To Transfer Drive Case | 1 |
175-2174 Lines Gp-Fuel
| 03***47 | Elbow-Filtered Fuel From Based Assembly | 2 |
| 03***42 | Seal-O-Ring; (11.89mm Id) | 8 |
| 0S***09 | Bolt (3/4") Filler Tube Assembly To Transfer Drive Case | 1 |
338-1882 Lines Gp-Fuel
| 03***47 | Elbow-Filtered Fuel From Based Assembly | 5 |
| 03***42 | Seal-O-Ring; (11.89mm Id) | 8 |
| 0L***51 | Bolt Starting Engine Fuel Tank Bracket To Diesel Intake Manifold | 4 |
174-7464 Mounting Gp-Fuel Line
| 17***64 | Mounting Group-Fuel Line | 1 |
| 9G***40 | Spacer; (10.5x25x15-mm Thk) | 1 |
| 9R***33 | Boss | 2 |
108-8757 Plug Gp-Fuel Lines
| 03***42 | Seal-O-Ring; (11.89mm Id) | 1 |
| 10***57 | Plug Group-Fuel Lines | 1 |
| 9S***91 | Plug,Machine Thread Fuel Injection Pump | 1 |
131-6589 Pump Gp-Fuel Injection
| 10***72 | Spacer; (9.8x15.85x37.6-mm Thk) | 1 |
| 13***89 | Pump Group-Fuel Injection | 1 |
| 21***26 | Injector Group-Fuel | 1 |
159-9823 Pump Gp-Fuel Prm & Sec Filter
| 13***41 | Pump Group-Fuel Priming; (Hand) | 1 |
| 15***91 | Base Group-Fuel Filter | 1 |
| 15***23 | Pump Group-Fuel Prm & Sec Filter | 1 |
139-9095 Pump Gp-Fuel Transfer
| 0S***73 | Stud | 2 |
| 10***72 | Cover; (Hydraulic Pump Drive) | 1 |
| 10***69 | Seal-O-Ring; (Fuel Transfer Pump) | 2 |
344-4005 Pump Gp-Fuel Transfer
| 0S***99 | Stud (1.4325" Long) | 2 |
| 10***69 | Seal-O-Ring; (Fuel Transfer Pump) | 2 |
| 13***16 | Cover | 1 |
139-9094 Pump Gp-Fuel Transfer
| 10***69 | Seal-O-Ring; (Fuel Transfer Pump) | 2 |
| 13***03 | Cover-Pump | 1 |
| 13***59 | Pump Group-Fuel Transfer | 1 |
233-6742 Valve Gp-Check -Fuel
| 23***42 | Valve Group-Check; -Fuel Filter | 1 |
| 23***96 | Valve Group-Check; -Fuel Filter | 1 |
| 6V***89 | Seal-O-Ring (Id=19.18mm) | 1 |
238-0296 Valve Gp-Check -Fuel
| 03***33 | Seal-O-Ring; (12.42mm Id) | 1 |
| 23***96 | Valve Group-Check; -Fuel Filter | 1 |
| 6V***23 | Ring; (Backup) (13.16mm Id) | 1 |
156-5783 Valve Gp-Check -Fuel
| 03***33 | Seal-O-Ring; (12.42mm Id) | 1 |
| 15***83 | Valve Group-Check; -Fuel | 1 |
| 6V***23 | Ring; (Backup) (13.16mm Id) | 1 |
139-6873 Valve Gp-Fuel Bypass -Filter
| 13***73 | Valve Group-Fuel Bypass; -Filter | 1 |
| 9X***37 | Seal-O-Ring | 1 |
Lubrication System
187-3313 Fastener Gp-Fumes Disposal
| 0S***09 | Bolt (3/4") Filler Tube Assembly To Transfer Drive Case | 1 |
| 18***13 | Fastener Group-Fumes Disposal | 1 |
| 5M***94 | Washer; Bracket To Tee, Bracket To Block, Tube As. To Tee, Tube As. To Oil Cooler | 1 |
4n-2481 Fastener Gp-Oil Pump Mounting -Engine
| 0L***43 | Bolt 63.5 mm (3/8" X 2 1/2" -Cover Assembly To Fender | 2 |
| 0S***90 | Bolt; (3/8-16x2in)(Clip Thru Spacer To Bracket As) | 1 |
| 4N***81 | Fastener Group-Oil Pump Mounting; Oil Pump Mounting Fastener Group | 1 |
6i-3944 Filler Gp-Engine Oil
| 06***55 | Seal-O-Ring (Id=47.22mm) | 1 |
| 06***97 | Cap-Oil Filler; (Engine Oil) | 1 |
| 24***42 | Tube As-Oil; (Filler) | 1 |
176-4109 Filter Gp-Engine Oil
| 0S***88 | Bolt,Machine; Hose Assembly Mounting,Hose Assembly To Transmission,And To Torque Converter | 7 |
| 0S***19 | Bolt,Machine Gear Retaining Part Of Kit P/N 1w***46 | 1 |
| 17***59 | Base Group-Oil Filter; (Engine) | 1 |
159-9362 Fumes Disposal Gp
| 15***62 | Fumes Disposal Group | 1 |
| 16***22 | Clip-Loop | 1 |
| 20***28 | Hose As; (Fumes Disposal) | 1 |
120-8972 Gauge As-Oil Level (Dipstick) -Engine
| 12***72 | Gauge As-Oil Level (Dipstick); -Engine | 1 |
121-4289 Gauge Gp-Oil Level (Dipstick) -Engine
| 12***89 | Gauge Group-Oil Level (Dipstick); -Engine | 1 |
161-1824 Guide Gp-Oil Level Gauge -Engine
| 0S***09 | Bolt (3/4") Filler Tube Assembly To Transfer Drive Case | 1 |
| 11***68 | Seal-O-Ring; (15.54mm Id) | 1 |
| 16***24 | Guide Group-Oil Level Gauge; -Engine | 1 |
138-2770 Lines Gp-Turbocharger Oil
| 0L***70 | Bolt (2-1/4") Filler Tube Assembly To Transfer Drive Case | 2 |
| 0S***71 | Screw,Cap,Hexagon; Tube Assembly To Turbocharger And Elbow Mounting | 2 |
| 10***44 | Elbow | 1 |
161-4113 Pump Gp-Engine Oil
| 12***56 | Cover As-Pump | 1 |
| 16***13 | Pump Group-Engine Oil | 1 |
| 1M***44 | Bolt; (3/8-16x2-1/4 In) | 2 |
C-18 serial number reference
The engine serial plate is a metal tag mounted on the engine block, typically on the left side near the front close to the valve cover; on installed truck or industrial units check behind the turbo housing if the block tag is not visible. The serial number is a 3-letter prefix followed by a sequential number (for example CJP01234). The prefix identifies the specific engine build and application, not the digits - use it to pull the correct parts and service manual for that unit.
| Prefix | Identifies | Notes |
|---|---|---|
| CJP | Truck engine | Primary C18 truck-engine prefix. Covered in a combined service and specifications manual alongside the C15 and C16 truck engines. Sources disagree on the exact truck application: some describe the C18 as off-highway only (haul trucks, heavy-haul/construction use), others tag CJP specifically as an on-highway truck build - treat as unresolved and confirm with your dealer using the full serial number. Exact model years not documented for this prefix specifically. |
| MDP | Truck engine | Truck-engine prefix grouped with CJP and MEP in the combined C15/C16/C18 truck manual set. Distinguishing rating or emissions tier versus CJP not documented - confirm with your dealer. |
| MEP | Truck engine | Truck-engine prefix grouped with CJP and MDP in the combined C15/C16/C18 truck manual set. Distinguishing rating or emissions tier versus CJP/MDP not documented - confirm with your dealer. |
| WJH | Industrial engine | Industrial/power-unit build of the C18 (pump drive, well-service, mechanical-drive applications), not a truck-chassis prefix. Dealer listings document this build around 630 hp at 2100 rpm - confirm exact rating with your dealer for your unit. |
| WRH | Industrial engine, twin-turbocharged-aftercooled | Industrial build reported in a twin-turbocharged-aftercooled configuration, a higher-output tier than the single-turbo WJH industrial build - dealer listings document this build up to roughly 800 hp. Confirm exact rating with your dealer. |
| EJG | Industrial engine | Industrial engine prefix. Exact power rating and model years not documented for this prefix specifically - confirm with your dealer. |
| C1J | Marine engine | Marine propulsion build of the C18. |
| CKH | Marine engine | Marine propulsion build of the C18. |
| CYN | Marine engine | Marine propulsion build of the C18. |
| KJT | Marine engine | Marine propulsion build of the C18. |
| NAX | Marine engine | Marine propulsion build of the C18. |
| NAY | Marine engine | Marine propulsion build of the C18, a companion rating to NAX. |
| DKE | Generator set | Generator-set build of the C18. |
| EKW | Generator set | Generator-set build of the C18. |
| STD | Generator set | Generator-set build of the C18. |
| STM | Generator set | Generator-set build of the C18. |
| G4C | Generator set | Generator-set build of the C18. |
| C6C | Generator set | Generator-set prefix. Exact power rating and model years not documented for this prefix specifically - confirm with your dealer. |
| MGS | Generator set | Generator-set prefix. Exact power rating and model years not documented for this prefix specifically - confirm with your dealer. |
| X6X | Power module | Skid/module-packaged C18 power module rather than a bare engine or standard generator set. |
Frequently asked questions
What engine does the Caterpillar C-18 use?
The C-18 designation is the engine itself, not a chassis. It is an 18.1 L (1,106 cu in) turbocharged and aftercooled inline-6 diesel, 145 mm (5.7 in) bore by 183 mm (7.2 in) stroke, 16.0:1 compression ratio, built in mechanical (HEUI) and later ACERT electronic fuel-system generations.
What is the operating weight of a Caterpillar C-18?
As a bare engine rather than a complete vehicle, the C-18's own dry weight runs roughly 1,270-1,790 kg (2,800-3,945 lb) depending on manifold type, aftertreatment, and accessories. The operating weight of the host truck, haul truck, or pump unit it powers is set separately by that OEM and is not part of the engine's own spec sheet.
What replaced the Caterpillar C-18?
Nothing has fully replaced it. The C-18 remains in current production for well-service, land-drilling, generator-set, fire-pump, marine, and off-highway truck ratings through Tier 4 Final/Stage IV. It succeeded the mechanical 3408 in this displacement class, and applications needing more power step up to the C27 or C32 ACERT rather than a direct C-18 replacement.
What C-18 owners discuss
What is the C-18 actually used for, and is it a factory on-highway semi engine?
The C-18 shares block architecture with the smaller C-15 but runs a larger bore and stroke, about 145 mm x 183 mm (5.71 in x 7.20 in) versus the C-15's 137 mm x 171 mm (5.40 in x 6.75 in), giving roughly 18.1 L (1,106 cu in) displacement. It was never sold as a mainstream over-the-road semi-tractor engine. Owners and technicians place it in vocational and severe-duty truck chassis such as fire apparatus and off-highway haul trucks, plus marine vessels, well-service rigs, and generator sets, where the extra displacement supports higher continuous output than the C-15. Rated output varies by application and series, roughly 429-597 kW (575-800 hp) across the platform. Check the engine's rating plate to confirm the specific configuration.
What turbo and aftercooler problems come up on high-hour C-18s?
Twin-turbo ACERT-series C-18s draw regular reports of turbo crossover-pipe wear and turbo failures tied to repeated heat-cycling, since clearances sized for cold assembly can pinch up once the engine has run hot for extended periods. Cracked hot-side turbo housings show up in the same discussions. Any turbo failure calls for pulling the air-to-air aftercooler core and flushing it, since compressor-side oil leakage deposits residue inside the core. On marine and genset C-18s, techs recommend replacing the aftercooler core on a roughly 6-year interval regardless of hours run, since internal corrosion works independent of runtime.
Is there a known crankshaft or bottom-end quirk on C-18s in heavy-haul truck service?
Heavy-haul truck operators running the C-18 report meaningful side-throw force on the crank under sustained load, with some units cracking near the bottom (rear) seal area and letting oil migrate into the cooling system. That is a different failure path than the far more common water-pump weep-hole leak, so oil showing up in the coolant on a C-18 is worth tracing past the water pump before calling it fixed. Because a cracked seal area affects crank sealing and lubrication, have your dealer verify the source with a proper teardown inspection before returning the engine to service.
What valvetrain wear pattern shows up in mechanic discussions?
Rocker-arm and camshaft fractures near the mounting bolt holes come up repeatedly, more often tied to stress concentration from incorrect torque on a prior rocker or camshaft service than to a base design flaw. A developing knock or tick from the valve cover area on a C-18 is worth investigating early rather than running it out. Because valvetrain component failure can send debris downstream into the oil system, have your dealer verify torque values and component condition on any camshaft or rocker service.
What causes most crank-no-start complaints, and is it usually the ECM?
Crank-no-start complaints on the C-18 trace most often to the fuel side before the ECM gets blamed: a clogged fuel filter, a weak transfer pump, or a faulty fuel-pressure regulator can drop cranking fuel pressure below the roughly 241 kPa (35 psi) needed to fire the engine. On marine and genset installs, a remote or emergency-stop switch left in the wrong state produces the same crank-but-no-start symptom with no fault code logged. Technicians pull the stored fault and event history from the engine's control module before chasing individual sensors, since an active code usually points straight at the failed component.
Does the C-18's injection and emissions system differ much across series?
Non-ACERT C-18s and early ACERT units use mechanically actuated, electronically controlled unit injection; injector trim coding and spray characteristics are not interchangeable between the two families. Later Tier 4 Final ACERT C-18s add a diesel particulate filter and oxidation catalyst with automatic regeneration that needs no operator input under normal conditions, but the system depends on ultra-low-sulfur fuel and a low-ash oil to stay healthy. Ash-service intervals are commonly cited around 5,000 hours, shorter if the engine spends a lot of time idling, as with a standby generator set. A high-soot-load fault that won't clear with an automatic regen usually means a forced stationary regen is needed rather than a component swap. Early ACERT examples reportedly needed more sorting-out than units built once the platform matured, so weigh a given engine's build era and service history rather than the family name alone.
What should I check before buying a used C-18?
Ask for service records first. A well-kept C-18 draws consistently positive reports, while a neglected one draws the opposite regardless of hours. Confirm when the aftercooler core was last serviced, especially on marine or genset units where a roughly 6-year replacement interval is the rule of thumb independent of hours run. Pull a blowby reading and a compression check rather than judging the engine on oil consumption alone. Older tolerance guidance put acceptable consumption around 11 L (3 gal) per 10,000 hours or miles depending on configuration, though this varies by series and has loosened in later production, so treat any number you're quoted as a guideline, not a guarantee. Check for oil in the coolant, which can mean a water pump or a cracked seal area, inspect turbo crossover plumbing on twin-turbo ACERT variants, and pull the control module's fault history if the seller allows access. Have your dealer verify blowby, compression, and any fault codes before you commit to the purchase.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
Serial-range & configuration variants
This page covers the Caterpillar C-18. Related factory variants of the same model family:
C18C18C18C18C18C18C18C18C18
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