QSK19 Series Overhaul Kits — In-Frame / Complete / Top-End

The Cummins QSK19 is a powerful 19-liter, six-cylinder diesel engine built to endure the most demanding applications across industrial, mining, locomotive markets. As part of Cummins’ Quantum Series, the QSK19 leverages electronic control systems and advanced combustion technology to deliver optimal performance, fuel efficiency, and long service intervals.

Designed as a heavy-duty evolution of the KTA19, the QSK19 incorporates high-pressure fuel injection, dual overhead camshafts (in certain variants), and a modular common rail system in later generations. This engine typically produces between 675 and 950 horsepower depending on the configuration, with reliable torque curves suited for both continuous duty and peak-load conditions.

Whether you operate a QSK19 in a mining haul truck or generator set, its longevity and output depend on periodic inframe overhauls with high-quality rebuild kits. ZEB Power proudly stocks complete overhaul kits, tools, gaskets, filters, and components to keep your QSK19 running like new.

Category Overview

Kit Type Selection: In-Frame vs. Complete vs. Top-End

QSK19 overhaul kits cover three rebuild scopes:

Top-End Kit

Cylinder head area only. Replaces head gasket, valve stem seals, and upper gasket set without disturbing the lower end. Applicable when compression loss is isolated to a single cylinder and crankcase blowby is absent, or when a head gasket failure is confirmed (coolant loss, white smoke, coolant contamination in oil) while piston ring and bearing condition remains serviceable. Not a substitute for in-frame overhaul if piston ring or bearing wear is present.

In-Frame Kit

Engine remains in the chassis. Replaces pistons, rings, liners, connecting rod bearings, and gaskets. Applicable when wear is confined to the upper end and main bearing clearance remains within Cummins specification (≤ 0.006 in / 0.152 mm). If compression test shows low cylinder pressure but oil pressure holds at rated speed, an in-frame rebuild is typically sufficient.

Complete Overhaul Kit

The engine fully disassembled. Adds main bearings, thrust washers, and camshaft bearings to the in-frame scope. Required when main bearing clearance exceeds tolerance, crankshaft journal shows taper or out-of-round beyond 0.001 in (0.025 mm), or sustained low oil pressure is confirmed. Attempting an in-frame rebuild on a worn crankshaft will not restore oil pressure.

If main bearing clearance has not been measured, sustained low oil pressure at rated speed (below 30 psi) is the field indicator that a complete overhaul is required rather than in-frame.

Kit Configuration by Compression Ratio

The QSK19 is produced in multiple compression ratio variants — primarily 13.9:1, 15.5:1, and a third special-variant group. Compression ratio is not a tuning parameter; it is a fixed geometric relationship determined at the factory by the combination of piston crown profile, cylinder liner bore diameter, and piston ring groove dimensions. Each variant uses components with different physical geometry, and these components are not interchangeable across compression ratio groups.

Specifically:

· Piston crown profile differs between variants — the crown height and combustion bowl geometry are machined to different specifications to achieve the target compression ratio
· Cylinder liner bore and wall thickness are matched to the piston specification of each variant; installing a liner from a different compression ratio group will produce incorrect piston-to-liner clearance
· Piston ring cross-section and groove dimensions are sized to match the specific piston used in each variant; ring sets from one compression ratio group will not seat correctly in a piston from another

As a result, the correct overhaul kit cannot be determined from the engine model designation alone. Cummins assigns a CPL (Control Parts List) number to each specific engine build configuration — the CPL encodes the compression ratio variant along with other build parameters. Each CPL maps to exactly one compression ratio group, and therefore to exactly one overhaul kit specification. Ordering must be done by CPL number, not by engine model or horsepower rating.

Symptoms Indicating an Overhaul Is Required

· Excessive oil consumption (above 0.5% of fuel consumption) — worn or stuck piston rings allowing oil into the combustion chamber
· High crankcase blowby pressure — compression gases bypassing rings, detectable at the crankcase breather outlet
· Progressive power loss — declining cylinder compression, confirmed below 400 psi per cylinder
· White or blue exhaust smoke under load — oil burning or coolant entering combustion from a failed head gasket
· Sustained low oil pressure (below 30 psi at rated speed) — main or connecting rod bearing wear; indicates complete overhaul scope
· Coolant loss without visible external leak — head gasket or liner seal failure

Single symptoms may indicate a component-level repair rather than full overhaul. Compression test and oil analysis results should confirm the rebuild scope before kit selection.

Recommended Overhaul Interval

· Mining / oil & gas (heavy continuous load): 10,000 – 12,000 hours
· Industrial / power generation (steady-state load): 12,000 – 15,000 hours
· Oil analysis trigger: iron content exceeding 150 ppm or copper exceeding 50 ppm in consecutive samples

Scheduled oil analysis is the most reliable method for determining actual overhaul timing independent of hour thresholds.

Compatibility Matrix

To select the correct overhaul kit for a QSK19 engine, locate the CPL number on the engine nameplate and match it to the corresponding compression ratio below.

CPL 2560 appears across multiple kit configurations — confirm with us before ordering.
CPL number not listed above? Submit an inquiry with your engine nameplate photo for confirmation.

Kit Contents

Kit contents vary by rebuild scope. The table below lists components included in each configuration.

Recommended co-replacement (not included in kit):
Individual component OEM part numbers available on request. Submit inquiry with CPL number(engine nameplate) and rebuild scope.

Quality Tier

QSK19 overhaul kits are available in three quality tiers. Selection depends on equipment requirements, budget, and downstream warranty obligations.

Considerations by tier:

· Genuine kits include Cummins-issued part traceability documentation, required for some insurance and warranty claim processes. Lead time depends on regional distributor stock.
· OEM-Equivalent kits are produced on the same tooling lines as genuine parts in many cases. The principal difference is packaging and documentation, not component specification. Suitable for the majority of commercial overhaul programs.
· Aftermarket quality varies significantly between suppliers. Critical dimensional tolerances — piston ring gap, bearing clearance, liner bore finish — should be verified against Cummins service manual specifications before installation.

Tier availability for specific CPL groups varies. Contact us with your CPL number and rebuild scope to confirm which tiers are in stock.

CPL Identification Guide

What the CPL number is

CPL (Control Parts List) is a 3–4 digit code assigned by Cummins to define the exact build specification of an engine — including compression ratio, fuel system calibration, and component configuration. Two QSK19 engines with different CPL numbers may require different overhaul kits even if their rated horsepower is identical. Ordering by engine model alone is insufficient.

Where to find it

The engine nameplate is located on the left side of the gear housing, below the valve cover. The nameplate lists the engine serial number (ESN), CPL number, and rated horsepower. The CPL field is labeled "CPL" followed by a numeric code.

Engine nameplate — QSK19

┌─────────────────────────────┐

│ Model:   QSK19              │

│ ESN:     XXXXXXXXX          │

│ CPL:     [3–4 digit code]   │ ← this is the number needed

│ HP:      XXX                │

└─────────────────────────────┘

How to use it

Match the CPL number against the compatibility matrix. The CPL determines which compression ratio group the engine belongs to, and therefore which overhaul kit applies.

If the nameplate is missing or unreadable

· Record the engine serial number (ESN) — Cummins can retrieve the CPL from ESN via their parts lookup system
· Submit the ESN with your inquiry and we will confirm the correct kit before order processing

Procurement & Logistics

Lead Time & Stock

· Genuine Cummins kits: subject to regional distributor availability; typical lead time 7–21 business days depending on CPL
· OEM-Equivalent kits: stocked for high-frequency CPL groups (13.9:1 variants); confirm availability at inquiry
· Special variant kits (CPL 2008–8079 group): lead time confirmed at order; typically 10–15 business days

Minimum Order

· Single kit orders accepted
· Volume pricing available for 3 units and above
· Fleet overhaul programs (10+ units) handled on a project basis — contact for dedicated lead time and pricing

Packaging

· Export wooden crate
· Individual components bagged and labeled
· Rust inhibitor applied to bare metal surfaces
· Gross weight approximately 78–80 kg per in-frame kit

Export Documentation

· Commercial invoice
· Packing list
· Certificate of Origin (on request)
· Any additional documentation required by destination customs confirmed at order

Shipping

· Sea freight (FCL / LCL): available to all major ports
· Air freight: available for urgent single-kit orders
· DDP / DAP terms available on request
· Transit damage: all shipments photographed pre-dispatch; damage claims supported with pre-shipment evidence

Warranty & After-Sales

Warranty Coverage by Tier

· Genuine Cummins kits: warranty terms follow Cummins standard policy; coverage period and conditions determined by regional Cummins distributor at point of sale
· OEM-Equivalent kits: 12 months from date of installation or 14 months from date of shipment, whichever occurs first; covers manufacturing defects in materials and workmanship
· Aftermarket kits: 6 months from date of shipment; dimensional conformance to Cummins service manual specifications is buyer's responsibility to verify prior to installation

Warranty Exclusions

· Damage resulting from incorrect kit selection (wrong CPL group)
· Installation without following Cummins QSK19 service manual torque specifications and procedures
· Engine overspeed, fuel contamination, or lubrication system failure
· Components modified or machined after delivery

Claim Process

· Step 1: Document the issue — photograph failed components, record engine hours at failure and CPL number
· Step 2: Submit claim within warranty period — provide photos, CPL, ESN, and order reference
· Step 3: Assessment within 5 business days — replacement or credit issued upon confirmation of manufacturing defect

Technical Support

· CPL and kit selection confirmation prior to order
· Cummins service manual torque specifications and assembly sequence available on request
· Installation query support via email — response within 1 business day

FAQ & Inquiry

Q1: What is the difference between an in-frame and complete overhaul kit for the QSK19?

An in-frame kit replaces pistons, rings, liners, connecting rod bearings, and gaskets with the engine remaining in the chassis. A complete kit adds main bearings, thrust washers, and camshaft bearings, and requires full engine disassembly.

Q2: How do I know which overhaul kit fits my QSK19?

Locate the CPL number on the engine nameplate on the left side of the gear housing and match it to the compatibility matrix on this page. If the nameplate is missing, the engine serial number (ESN) can be used to retrieve the CPL through Cummins parts lookup.

Q3: Can I use a KTA19 overhaul kit on a QSK19 engine?

No. The QSK19 uses an electronic fuel system and different piston architecture from the mechanically-fueled KTA19 — overhaul kits are not interchangeable between these two series.

Q4: Does compression ratio affect which kit I need?

Yes. The QSK19 is built in 13.9:1 and 15.5:1(also have other compression ratio) compression ratio variants, each requiring a different piston, ECM, Injector specification. Using the wrong kit will result in incorrect compression and potential engine damage.

Q5: What are the signs that a QSK19 engine needs an overhaul?

Key indicators include excessive oil consumption, high crankcase blowby pressure, progressive power loss, and sustained low oil pressure below 30 psi at rated speed. A cylinder compression test below 400 psi per cylinder confirms the need for an overhaul.

Q6: Should piston cooling nozzles be replaced during an overhaul?

Piston cooling nozzles are not included in standard overhaul kits but should be inspected at every in-frame rebuild. Restricted nozzles cause piston crown overheating and accelerated ring wear, and replacement is recommended if any restriction is found.

Q7: What documents are available for customs clearance?

Standard export documentation includes commercial invoice, packing list, and certificate of origin.

Inquiry

To receive a quote or confirm kit availability for your CPL, provide the following:

· Engine nameplate and CPL number
· Rebuild scope: Top-End / In-Frame / Complete
· Required quality tier: Genuine / OEM-Equivalent / Aftermarket
· Destination port and required documentation

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