Cummins QSK 19 Engine Parts - Oil Section

Cummins QSK19 Engine Parts – Oil System Section

The lubrication system in the Cummins QSK19 engine plays a central role in ensuring durability, performance, and efficiency. At the heart of this system is a complex network of oil coolers, filters, gaskets, O-rings, and pressure switches—each critical to delivering clean, temperature-controlled oil to all moving parts. Whether you're performing routine maintenance or a complete overhaul, Diesel Pro Power offers the parts and expertise needed to keep your QSK19’s oil system operating flawlessly.

With over 40,000 satisfied customers worldwide, Diesel Pro Power is a trusted source for QSK19 components, offering rapid global shipping and technical support to marine, mining, and industrial operations.

The Importance of Oil System Integrity on the QSK19

The QSK19’s inline-6 design and high-horsepower rating mean it operates under extreme pressure and heat. This makes the lubrication system critical for:

• Minimizing friction and wear on internal components
  
  

• Cooling pistons, camshaft, and crankshaft via oil jets
  
  

• Protecting turbochargers and fuel systems from contamination
  
  

• Maintaining consistent pressure and flow under load
  
  

Failures in any oil system component—whether it's a leaking gasket or clogged filter—can cause a chain reaction leading to bearing failure, overheating, and engine seizure. That’s why using high-quality, OEM-compatible oil system parts is essential.

Cummins QSK19 Oil Coolers

Primary Oil Cooler – QSK19

The main oil cooler is responsible for reducing the temperature of engine oil as it circulates through the block. It is installed between the oil pump and the main oil gallery, and it exchanges heat with the engine's coolant system.

Features:

• Multi-plate core design for maximum cooling surface area
  
  

• Pressure-tested for marine and industrial use
  
  

• Helps prevent thermal breakdown of oil
  
  

• Maintains safe viscosity and pressure in high-load conditions
  
  

Oil coolers should be replaced when internal clogging, oil-to-coolant cross-contamination, or visible corrosion is observed. A failing cooler can lead to rising oil temperatures and potential engine damage.

Dual Cooler Configuration

Certain QSK19 engine builds, particularly marine propulsion models, may feature dual oil coolers. This design increases oil cooling efficiency and is essential in continuous-duty environments where oil heat load is high.

Oil Cooler Gaskets, Covers & Seals

Replacing the oil cooler? Don't forget the gaskets and seals that ensure a leak-free installation. These components are critical to maintaining oil and coolant separation.

Oil Cooler Gasket

This gasket seals the interface between the oil cooler and the block. Designed to handle oil pressure and coolant routing, it prevents leaks and cross-contamination.

Oil Cooler Cover Gasket

Used to seal the removable end cover of the oil cooler assembly. This gasket should always be replaced if the cover is removed for inspection or service.

Oil Cooler O-Ring

A small but critical sealing element that ensures tight passage seals inside the cooler housing. A degraded O-ring can result in internal oil or coolant leaks that are difficult to detect externally.

Oil Cooler Housing Gasket

This gasket seals the outer housing to the engine and supports the mounting of oil routing components. Flat and pressure-resistant, it’s engineered for long-term stability under temperature and vibration.

Oil Pan Adapter Gaskets

The QSK19 engine uses a multi-piece oil pan configuration, which includes upper and lower adapter gaskets. These gaskets form the seal between the block and the oil pan components.

Upper Oil Pan Adapter Gasket

Used to seal the oil pan adapter flange to the lower part of the engine block. Must withstand both oil pressure and expansion-related vibration.

Lower Oil Pan Adapter Gasket

Installed between the oil pan adapter and the oil pan itself. Critical for preventing oil seepage at the bottom of the crankcase. Replace this gasket any time the oil pan is removed for inspection or cleaning.

Cummins Oil Filters for QSK19

Spin-On Oil Filter – QSK19

The spin-on oil filter for the QSK19 engine is designed to remove carbon, sludge, metal, and other particulates from engine oil. This large-format filter features:

• High-flow media for consistent filtration
  
  

• Heavy-duty canister for high-pressure systems
  
  

• Anti-drainback valve to maintain oil in the filter when the engine is off
  
  

• Easy spin-on installation with a 2¼" threaded fitting
  
  

Regular oil and filter changes are essential for long engine life. The QSK19 engine typically requires frequent filter replacement, especially in harsh-duty cycles such as marine towing or mining haul truck use.

Oil Filter Removal Wrench

Changing a spin-on filter is made easier with a heavy-duty oil filter wrench. Our adjustable oil filter wrench accommodates large-diameter filters—ideal for Cummins, Detroit Diesel, and Caterpillar engines.

Features:

• Adjustable diameter from 4-21/32" to 5-5/32"
  
  

• Designed for tight engine compartments
  
  

• Helps prevent filter damage during removal
  
  

Using a proper filter wrench reduces the risk of cracking the filter body or overtightening new filters.

Oil Pressure Switches – QSK19

Oil pressure switches monitor lubrication system performance and help protect the engine from damage by triggering alarms or shutdown protocols. QSK19 engines may use one or more of the following pressure switches, depending on configuration.

5 PSI Make/Break Switch

Triggers an alert if oil pressure drops below 5 PSI. Used in low-speed marine or industrial idle conditions to protect the engine during start-up.

10 PSI Make/Break Switch

Provides a more aggressive response, often used in continuous-duty gensets or marine vessels where rapid oil pressure loss needs immediate action.

20 PSI Make/Break Switch

Installed on engines operating at higher baseline pressures. Ideal for load-bearing engines with advanced engine control modules (ECMs).

27 PSI Make/Break Switch

Used in highly sensitive applications, including dual ECM control systems or marine propulsion setups with automated engine room safety systems.

Installation Notes:

• All switches include 1/8" NPT thread
  
  

• Always verify system voltage and alarm wiring before replacement
  
  

• Switch failures can mimic true pressure loss—diagnose carefully
  
  

Marine Zinc Anode for Oil Coolers

Zinc Anode Plug

Used in marine QSK19 engines to prevent galvanic corrosion inside oil and fuel coolers. This zinc anode installs directly into the cooler housing and sacrificially corrodes instead of the cooler itself.

Key Specs:

• Brass plug with integrated zinc core
  
  

• Standard NPT 3/8" thread
  
  

• 1" zinc element length
  
  

When to Replace:

• Zinc is 50% depleted
  
  

• Surface is deeply pitted
  
  

• During scheduled cooler maintenance or oil changes
  
  

Failing to replace anodes can lead to premature cooler corrosion and internal leakage.

Hand Hole Cover Gasket

This gasket seals the inspection ports on the side of the QSK19 engine block. While not a primary oil flow path, these covers provide access to internal oil channels, so a tight seal is critical to preventing weepage and contamination.

Use Cases:

• After bearing or piston inspection
  
  

• Replacing liners or cleaning crankcase
  
  

• Leak repair on the engine block side
  
  

Always clean the mating surface thoroughly before re-installing the gasket.

QSK19 Lower Gasket Set – Oil System Inclusions

The full lower gasket set includes many of the oil-related gaskets and seals necessary for a complete engine rebuild or bottom-end overhaul.

What’s Typically Included:

• Crankshaft front and rear seal kits
  
  

• Oil pan gaskets
  
  

• Oil cooler seals and O-rings
  
  

• Gear train cover gaskets
  
  

• Oil jet seals
  
  

• Hand hole cover gaskets
  
  

• Oil passage plugs and grommets
  
  

Using a complete gasket set saves time and ensures no vital seals are missed during engine reassembly.

Best Practices for Servicing the QSK19 Oil System

1. Regular Oil Sampling and Analysis

Monitoring for trace metals, soot content, and fuel dilution can identify internal wear and oil breakdown long before catastrophic failure occurs.

2. Replace Gaskets and O-Rings with Every Service

Never reuse oil system gaskets. Heat cycling and chemical exposure degrade rubber and composite materials over time.

3. Pressure Test the Oil Cooler

During overhaul or after a suspected oil/coolant leak, pressure test the oil cooler to verify integrity.

4. Check for External Leaks

Oil film on the crankcase, oil pan, or gear housing may indicate failing gaskets or improperly torqued fasteners.

5. Use Manufacturer-Specified Filters and Fluids

The QSK19’s high flow and high-pressure oil system requires filters and oil that meet or exceed Cummins standards.

Why Diesel Pro Power for Cummins QSK19 Oil System Parts?

• OEM-Compatible Quality: Gaskets, filters, and coolers that match factory specs
  
  

• Fast Global Delivery: Same-day shipping on most items
  
  

• Complete Kits Available: Gasket sets, seal kits, and filter tools in one place
  
  

• Marine & Industrial Specialists: Support for tugboats, barges, gensets, mining, and more
  
  

• 40,000+ Satisfied Customers: Trusted worldwide for diesel engine parts