Cummins L10 Parts – Camshaft & Related Components

Engine Specifications & Applications

The Cummins L10 engine was introduced in the 1980s as a mid-range diesel engine designed for heavy-duty trucks, buses, industrial applications, and marine use. With a displacement of 10 liters, the L10 offered a balance between the lighter Cummins 6CTA series and the larger heavy-duty N14. Known for its rugged construction, mechanical reliability, and straightforward serviceability, the L10 quickly became a staple powerplant in many industries.

• Displacement: 10 liters

• Configuration: Inline 6-cylinder, 4-stroke diesel

• Bore and Stroke: 125 mm x 136 mm (4.92 in x 5.35 in)

• Compression Ratio: Typically around 16.5:1, depending on application

• Horsepower Range: 240 – 330 HP, with higher ratings in certain configurations

• Torque Output: 800 – 1,050 lb-ft

• Fuel System: Mechanical injection in earlier models, electronic control in later versions

• Cooling System: Water-cooled, with marine applications utilizing raw water pumps

• Applications: Heavy trucks, buses, construction equipment, marine propulsion, and generator sets

The Cummins L10 is widely respected for its ability to run high mileage or extended hours between overhauls. A key to this longevity lies in the camshaft and related components, which control valve timing, fuel delivery, and overall breathing efficiency of the engine.

Importance of the Camshaft in the Cummins L10

The camshaft is often called the “heartbeat” of the engine. In the Cummins L10, it coordinates the opening and closing of the intake and exhaust valves with the movement of the pistons. Proper camshaft function ensures that air, fuel, and exhaust gases flow in and out of the combustion chambers at precisely the right time.

Without a properly functioning camshaft and its supporting components—such as bushings, seals, and gaskets—the L10 cannot maintain its performance or reliability. Camshaft wear can lead to poor fuel economy, power loss, increased emissions, and eventually catastrophic engine failure.

Parts Catalog: Camshaft & Related Components for Cummins L10

Camshaft Bushing Set for Cummins L10

The camshaft bushings serve as the bearings that support the camshaft within the block. Over time, these bushings can wear down due to oil contamination, improper lubrication, or simply long service hours.

• Function: Maintain camshaft alignment and reduce friction.

• Symptoms of Wear: Knocking noise from valve train, excessive endplay, uneven camshaft wear.

• Maintenance Tip: Always replace bushings during a major overhaul. Properly lubricate with assembly lube during installation.

Rocker Cover Housing Gasket for Cummins L10

The rocker cover housing gasket seals the top of the cylinder head and prevents oil from leaking into the atmosphere. A worn or cracked gasket can lead to oil leaks, which not only cause mess and maintenance issues but also lower engine oil pressure.

• Function: Prevents oil leaks from the rocker arm housing.

• Symptoms of Wear: Visible oil seepage, smell of burning oil, low oil level over time.

• Maintenance Tip: Inspect gaskets during routine service. Replace immediately if hardened, cracked, or compressed.

Front Cover Seal Ring for Cummins L10

The front cover seal ring ensures that the timing gear area remains sealed and free of oil leaks. Because the camshaft passes through this housing, the seal prevents oil from escaping while still allowing the camshaft to rotate smoothly.

• Function: Keeps engine oil inside the timing gear housing.

• Symptoms of Wear: Oil leaks at the front of the engine, oil dripping near crankshaft damper or gear cover.

• Maintenance Tip: Replace whenever the gear housing is removed. Inspect sealing surfaces for grooves or scoring.

Rectangular Ring Seal for Cummins L10

The rectangular ring seal is a small but crucial component within the L10 camshaft and gear housing system. It provides a secure seal for high-pressure oil pathways, preventing leakage and ensuring that lubrication reaches critical areas.

• Function: Provides oil sealing for specific camshaft housing passages.

• Symptoms of Wear: Oil weeping around the camshaft gear cover, unexplained oil pressure loss.

• Maintenance Tip: Replace with every overhaul or component disassembly, as seals can harden over time.

Rear Cover Plate Gasket for Cummins L10

The rear cover plate gasket seals the back of the engine’s camshaft housing. This gasket must withstand oil pressure, vibration, and heat cycles. A leak here can contaminate the flywheel housing, leading to clutch or transmission issues.

• Function: Provides oil sealing at the rear camshaft housing.

• Symptoms of Wear: Oil dripping from the rear of the engine, oil spray on flywheel housing.

• Maintenance Tip: Always replace with a new gasket during disassembly. Apply torque in a cross-pattern when reinstalling.

Gear Cover Plate Gasket for Cummins L10

The gear cover plate gasket seals the gear train compartment, which includes the camshaft gear, idler gears, and fuel pump drive gear. Proper sealing ensures that engine oil stays within the gear housing.

• Function: Seals the gear train cover and prevents leaks.

• Symptoms of Wear: Oil seepage around the gear housing, low oil level due to leakage.

• Maintenance Tip: Use high-quality gaskets and proper torque specs. Ensure surfaces are clean and free from debris before installation.

Maintenance Considerations for Cummins L10 Camshaft Components

• Regular Oil Changes: Clean oil prevents camshaft bushing wear.

• Scheduled Inspections: Look for oil leaks at gaskets and seals.

• Proper Torqueing: Over-tightening can distort covers and lead to leaks.

• Use of OEM-Quality Components: Ensures correct fitment and long-term reliability.

Common Failure Symptoms in the L10 Camshaft System

• Excessive Valve Noise: Could indicate worn camshaft bushings or lobes.

• Oil Leaks: Often caused by failed seals or gaskets.

• Engine Misfire or Power Loss: Improper camshaft timing due to excessive play.

• Contaminated Oil: Metal particles may indicate bushing wear.

Installation & Service Tips

• Always pre-lubricate camshaft bushings before installation.

• Ensure camshaft endplay is within factory specifications.

• Use new gaskets and seals whenever covers are removed.

• Keep mating surfaces clean to prevent sealing failures.

• Follow recommended torque values for all cover bolts.

Why Choose Diesel Pro Power for Cummins L10 Camshaft Components?

With 40,000+ satisfied customers worldwide, Diesel Pro Power is the trusted source for Cummins L10 parts. Every camshaft component—from bushings to gaskets—is backed by fast shipping, technical support, and a commitment to keeping your engine running reliably.