Engine Assemblies, Complete Diesel Engines for Heavy Equipment
When the cost of an in-field rebuild exceeds the machine's operational value, or downtime demands a faster solution than a full overhaul, a replacement engine assembly is the right path. At Imara Engineering, we stock used, reconditioned, and rebuilt diesel engines for excavators, dozers, wheel loaders, and heavy plant, each matched to your machine's original specification and dispatched with full supporting documentation. Our Engine Assemblies range carries three dedicated brand collections:
Cummins Engines for Sale
The Cummins engine family is one of the most widely deployed diesel platforms in heavy equipment and over-the-road applications globally. Our Cummins Engines for Sale collection covers the full model spectrum from compact units through to high-output configurations built for the most demanding plant applications.
- 4BT & 6BT — compact and mid-range workhorses for excavators, light plant, and agricultural equipment
- N14, M11 & L10 — high-torque platforms for demanding earthmoving and haulage applications
- ISX, ISX15 & X15 — modern high-output Cummins engines for heavy plant and over-the-road use
- 855 & Big Cam 400 — proven legacy configurations with strong global parts availability
Every Cummins engine is cross-referenced to your machine serial number before dispatch. Worldwide shipping available.
Caterpillar Engines for Sale
CAT diesel engines power some of the most demanding machines in mining, civil construction, and bulk earthmoving worldwide. Our Caterpillar Engines for Sale collection covers new, used, and remanufactured units across the full CAT diesel range with OEM specifications verified and serial numbers cross-referenced before every order ships.
- C7, C9, C12, C13 — mid-range CAT engines for excavators, motor graders, and medium plant
- C15, C15 ACERT, C16, C18 — high-output CAT powerplants for large excavators and heavy haul
- 3306, 3406, 3406E, 3406B — the most widely rebuilt CAT engines in heavy industry worldwide
- 3208, 3116, 3126 — reliable multi-application diesel platforms with broad fitment coverage
Detroit Diesel Engines for Sale
Detroit Diesel engines are trusted in heavy haulage and high-cycle plant applications worldwide, known for their torque output and operational durability. Our Detroit Diesel Engines for Sale collection covers rebuilt and used units across the full Detroit range, dispatched with documented rebuild specifications and full worldwide delivery capability.
- DD13 & DD15 — modern Detroit platforms for on-highway and heavy plant applications
- DD16 — Detroit's highest-output platform for maximum-duty applications
- Series 60 (12.7L & 14L) — the legendary Detroit platform with strong global parts availability and support
Cylinder Heads: Combustion Integrity for CAT, Cummins & Komatsu Engines
The cylinder head seals the top of the combustion chamber, manages intake and exhaust valve operation, and channels coolant and oil through the engine block. When a head cracks, warps, or becomes porous, a failure mode particularly common on the CAT C15 ACERT and 3406E under sustained high-load operation, coolant enters the combustion chamber, compression drops, and catastrophic internal damage follows rapidly if operation continues. At Imara Engineering, all cylinder heads are pressure-tested and surface-checked before dispatch.
Our cylinder head range covers:
- CAT: C7, C9, C12, C13, C15, C15 ACERT, 3116, 3126, 3306, 3406, 3406E
- Cummins: N14, ISX, ISX15
- Komatsu: major platform variants available on request
Cylinder Liners; Precision Bore Surfaces for Engine Block Integrity
Cylinder liners form the precision wear surface inside the diesel engine block that pistons travel through on every combustion cycle. In wet-liner configurations standard across Caterpillar and Komatsu platforms, coolant contacts the liner's outer surface directly, creating cavitation erosion risk under high-cycle excavator loads over time. A worn or out-of-round liner causes blow-by and compression loss that is frequently misdiagnosed as ring failure before the bore is properly measured and inspected.
Key signs your cylinder liners need attention:
- Elevated oil consumption with no visible external leak
- Compression loss across multiple cylinders on a leakdown test
- Excessive blow-by and crankcase pressure build-up
- Visible bore scoring or pitting on internal inspection
Imara supplies cylinder liners for CAT C15, 3406E, and other major diesel engine blocks available individually or in matched sets for a complete engine rebuild. We recommend replacing liners and pistons together on any full overhaul.
Pistons & Piston Rings; Compression Sealing Under Extreme Load
Pistons and rings endure thermal and mechanical stress on every firing cycle of the engine. Worn top rings allow combustion pressure to escape past the piston, a condition known as blow-by, leading to crankcase pressurisation, oil contamination, and accelerated bearing wear throughout the engine. The CAT C15 ACERT is particularly known for piston ring wear at high engine hours, as are the 3406 and 3406E under sustained heavy-duty operation.
Our pistons and rings range covers:
- CAT: C15, C15 ACERT, 3306, 3406, 3406B, 3406E, 3208
- Cummins: ISX and other major diesel platforms
- All parts dimensioned to OEM tolerances for correct ring gap, end seal, and full service life
Gasket Kits & Engine Rebuild Kits; Complete Overhaul in One Order
A rebuild is only as reliable as its sealing system. A failed head gasket, incorrect valve stem seal, or compromised rear main seal can undo an entire engine overhaul within hours of restart. At Imara Engineering, we supply individual gasket sets, head gasket kits, and complete engine overhaul and rebuild kits bundled to cover everything required for a top-end or full engine rebuild in one consolidated order.
Our rebuild kit range covers:
- CAT C7, C12, C13, C15, C15 ACERT, 3306, 3406, 3406B, 3406E
- Every kit is supplied as a complete set, not piecemeal components that leave gaps in your order
- Ideal for workshop managers and fleet operators planning a complete engine overhaul
Crankshafts: Rotating Precision for Heavy Diesel Engines
The crankshaft converts piston reciprocating motion into the rotational force that drives your machine. Main bearing failure, journal wear, or fatigue cracking produces severe vibration, knocking, and eventual engine seizure. Unlike most engine components, crankshaft damage is rarely recoverable through field repair; replacement is the only reliable path forward.
Our crankshaft range covers:
- CAT: C15, C16, C18, 3406, 3406B, 3406E
- Cummins: N14, ISX, ISX15
- Detroit Diesel: DD15
- All precision-ground, dynamically balanced, and dispatched with full journal dimension documentation for main and rod bearing matching
Camshafts; Valve Timing Precision for High-Performance Diesel Engines
The camshaft controls the precise timing and lift profile of every intake and exhaust valve in the engine. Lobe wear and spalling reduce power output, increase fuel consumption, and raise exhaust emissions, and are frequently mistaken for injector or fuel system faults before the camshaft is properly inspected. The CAT C15 ACERT camshaft is a well-documented high-wear component at elevated engine hours, making early inspection and proactive replacement a priority during any C15 ACERT rebuild.
Our camshaft range covers:
- CAT: C15, C15 ACERT, 3406B
- Cummins: N14, ISX, ISX15
- All manufactured to OEM lift profiles, duration specifications, and base circle tolerances
Oil Pumps; Engine Lubrication Without Compromise
Oil pressure is the lifeblood of every diesel engine. A failing oil pump starves bearing surfaces of lubrication within minutes, and by the time low oil pressure registers on the instrument panel, internal damage is often already severe and progressive. Oil pump wear accelerates in high-hour diesel engines where internal clearances have grown beyond specification.
Our oil pump range covers:
- CAT: C7, C9, C12, C13, C15, 3406B, 3406E
- Cummins: N14, ISX, ISX15
- All supplied to OEM flow rate and pressure specifications and verified before dispatch
Water Pumps; Coolant Circulation for Excavators & Heavy Plant
Overheating is one of the leading causes of catastrophic engine failure in excavators and heavy plant equipment. Impeller wear, seal failure, and bearing collapse reduce coolant circulation, creating localised thermal stress in the cylinder head and block that leads directly to head gasket failure and cylinder head warping. The CAT C15 ACERT, 3406E, and Komatsu PC200-8 are particularly susceptible to water pump wear under high-cycle operation.
Our water pump range covers:
- CAT: C7, C9, C13, C15, C18, 3208, 3306, 3406, 3406E, C15 ACERT
- Cummins: 4BT, 6BT, N14, M11, ISX, ISX15
- Komatsu: PC200-8
- All matched to OEM flow rate and pressure specifications for each specific engine platform
Alternators: Heavy-Duty Charging Systems for Diesel Equipment
The alternator sustains charge across every electrical circuit on your machine, from engine management and starter circuits to instrument panels, control systems, and field lighting. A failed alternator discharges the battery rapidly, causing uncontrolled system shutdowns and stranded equipment in the field, commonly at the worst possible operational moment. Heavy-duty diesel alternators experience accelerated wear in the high-vibration, high-temperature environments typical of excavator and mining plant applications.
Our alternator range covers:
- CAT: 3208, C13, C15, C15 ACERT, 3116, 3126
- Cummins: 4BT
- All units are tested to OEM voltage output and amperage ratings before dispatch
Starter Motors: Reliable Engine Starting for Any Condition
In remote field operations, cold-climate environments, or high-cycle fleet applications, a reliable starter motor is not optional; it is operationally critical. Starter failure is rarely sudden. It progresses through a recognisable sequence that experienced operators learn to identify early:
- Slow or laboured cranking under normal operating conditions
- Intermittent starting, the engine turns over on some attempts but not others
- A single click on ignition with no engine movement, solenoid engaging, motor not responding
- Complete failure to turn over under any condition
Imara Engineering stocks starter motors for CAT C15, C15 ACERT, 3306, 3208, Cummins, and Komatsu platforms rated to OEM cranking torque and duty cycle specifications and individually tested before every dispatch.
Engine Accessories: Thermostats, Belts & Tensioners for Heavy Diesel Engines
Engine longevity depends on more than the core rotating assembly. The ancillary systems that regulate operating temperature, drive the alternator and cooling fan, and maintain belt tension directly determine service intervals and overall engine reliability. Our Engine Accessories range covers three dedicated sub-collections:
Thermostats
A thermostat stuck open causes chronic under-temperature operation, increasing fuel consumption and accelerating cylinder bore wear. One stuck closed overheats the engine within minutes. We stock thermostats for CAT C7, C13, C15, C15 ACERT, 3126, 3208, and 3406, all manufactured to OEM opening temperature specifications for each engine platform.
Engine Belts
Fan belts, alternator belts, and serpentine drive belts are planned wear items that require inspection and scheduled replacement at regular service intervals. A snapped belt on a working machine immediately disables ancillary systems and can cause rapid overheating if the cooling fan drive is affected. We stock engine belts for CAT C7, C13, C15, C15 ACERT, and 3406E matched to OEM dimensional specifications.
Belt Tensioners & Idler Pulleys
Tensioner bearing failure and seized idler pulleys cause accelerated belt wear and eventual snap, often without prior warning. The CAT C15 and C15 ACERT tensioner systems are well-documented high-wear components at elevated engine hours. We stock belt tensioners and idler pulleys for CAT C15, C15 ACERT, C13, and Cummins ISX platforms.
Why Source Your Engine Parts from Imara Engineering?
Fleet managers and operators across Australia, North America, Canada, and internationally choose Imara Engineering because we combine the technical depth of a specialist diesel parts supplier with the reach of a global shipping operation. Here is what sets us apart:
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OEM-Equivalent Quality — Parts manufactured to the same dimensional and performance standards as original equipment. Aftermarket means the same engineering integrity at a more competitive price point.
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Confirmed Fitment Before Every Dispatch — Every order is cross-referenced against your machine serial number and engine model. Right part, right fit, first time, no costly returns or downtime from incorrect components.
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Deep Inventory Across All Major Platforms — CAT, Cummins, Komatsu, Detroit Diesel — critical components held in stock and available to ship fast, without extended back-order lead times.
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Fast Worldwide Shipping — We dispatch to Australia, the USA, Canada, and internationally with full order tracking from point of dispatch through to delivery.
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Specialist Technical Knowledge — When you contact Imara Engineering, you speak with people who understand heavy diesel engines at a technical level. We know the difference between a 3406B and a 3406E, a C15 and a C15 ACERT, and we source accordingly.
