Piston Ring Set Genuine OEM 23040-2G200

23040-2G200 STD Engine Piston Ring Set Product Overview

The 23040-2G200 Piston Ring Set is a standard-size engine internal replacement component designed primarily for selected Hyundai and Kia 2.4L gasoline engine applications. The official Hyundai catalog description is Ring Set-Piston, with Hyundai part code 23040A and manufacturer specification STD (Standard Size). OE number 23040-2G200 also supersedes the earlier 23040-25200 piston ring set.

This piston ring set is installed in the grooves around the engine pistons and operates directly against the cylinder walls. Its primary functions are to maintain combustion-chamber sealing, preserve cylinder compression, control the amount of lubricating oil on the cylinder wall, reduce excessive blow-by, and transfer heat from the piston toward the cylinder block.

The 23040-2G200 is particularly associated with Hyundai/Kia 2.4L 2359 cc L4 DOHC applications. Independent OE-fitment references identify it with the G4KE / Theta II 2.4L engine family, while Hyundai's own parts diagram specifically lists 23040-2G200 for 2.4L Theta II configurations. 

.

Core Product Specifications

Specification Notice: The Hyundai-listed 7.8 × 6.2 × 3.1 in measurement should be treated as a catalog/package dimension. It should not be described as the diameter, width, or thickness of the individual piston rings.

Product Features

STD Standard-Size Replacement

The STD designation is an important specification of 23040-2G200.

It means this piston ring set is intended for an engine using the original standard cylinder and piston size rather than an oversize repair configuration. Hyundai catalogs separately list oversize piston-ring part numbers for relevant engines, confirming that 23040-2G200 itself is the standard-size specification.

Before installation, the cylinder bore should still be professionally measured to determine whether a standard-size ring set remains suitable for the engine.

Designed for 2.4L Theta II Applications

Hyundai's parts catalog identifies 23040-2G200 for 2.4L Theta II applications, while related fitment references associate the OE number with the 2.4L 2359 cc G4KE engine. 

This makes the part suitable for engine repair and overhaul applications where the original OE reference and standard-size specification match.

Reliable Combustion Sealing

During compression and combustion, cylinder pressure rises rapidly.

The piston rings form a sealing interface between the moving piston and stationary cylinder wall. Correct sealing helps retain combustion pressure above the piston and supports efficient conversion of combustion energy into engine power.

Engine Oil Control

The piston-ring system regulates the lubricating oil film on the cylinder wall.

It allows sufficient lubrication for piston movement while helping remove excess oil before it enters the combustion chamber.

Proper oil control helps reduce:

• Excessive engine oil consumption

• Blue exhaust smoke

• Oil-fouled spark plugs

• Carbon deposits

• Combustion-chamber contamination

Heat Transfer

Pistons operate in an extremely hot environment.

Piston rings provide part of the heat-transfer path between the piston and cylinder wall, allowing heat generated in the piston to move toward the engine block and cooling system.

Precision Fit for Engine Overhaul

Correct piston-ring geometry and clearance are important because the rings operate continuously at high speed while exposed to:

• Combustion pressure

• High temperature

• Continuous sliding friction

• Engine oil

• Rapid acceleration and deceleration

• Thousands of combustion cycles per minute

For this reason, piston rings should be installed only after checking the piston grooves and cylinder condition.

Product Function

The 23040-2G200 Piston Ring Set performs three primary functions inside the engine.

1. Maintain Cylinder Compression

The compression rings help prevent combustion gases from escaping through the clearance between the piston and cylinder wall.

Good sealing supports:

Stable Compression → Efficient Combustion → Consistent Power Output

When the rings become worn, damaged, or stuck, cylinder pressure can leak into the crankcase and cause engine performance problems.

2. Control Engine Oil Consumption

Engine oil must lubricate the cylinder wall, but excessive oil cannot be allowed to remain inside the combustion chamber.

The oil-control portion of the piston ring system removes excess oil while maintaining the lubricating film required for piston movement.

Correct oil control helps reduce oil burning and exhaust smoke.

3. Transfer Heat from the Piston

The piston absorbs substantial combustion heat.

Part of this heat moves:

Piston → Piston Rings → Cylinder Wall → Engine Block

This heat-transfer function helps protect the piston against excessive thermal loading.

What Does 23040-2G200 Do Inside the Car?

The 23040-2G200 piston ring set operates inside the engine cylinders every time the engine is running.

During the combustion cycle:

Air and fuel enter the cylinder
↓
The piston compresses the mixture
↓
Combustion creates cylinder pressure
↓
Piston rings seal the piston-to-cylinder clearance
↓
Combustion pressure pushes the piston downward
↓
Connecting rod transfers force to the crankshaft
↓
Engine produces usable torque

At the same time, the rings continuously control cylinder-wall lubrication and transfer piston heat.

Therefore, although piston rings are relatively small engine components, they have a direct influence on:

• Compression

• Engine power

• Oil consumption

• Exhaust emissions

• Blow-by

• Engine durability

Compatible Hyundai Applications

Hyundai's OE catalog lists 23040-2G200 for the following applications:

Hyundai's crankshaft-and-piston catalog further identifies 23040-2G200 specifically with 2.4L Theta II Tucson configurations. 

Additional Hyundai / Kia 2.4L Applications

OE-fitment references also associate 23040-2G200 with several Hyundai/Kia 2.4L 2359 cc L4 DOHC vehicles, including:

These applications are independently cross-referenced to OE 23040-2G200 and a 2.4L / 2359 cc engine configuration. 

Important: Fitment can vary by market, production date, engine revision, and vehicle configuration. Always verify the OE number + VIN + engine code before ordering.

Common Problems and Solutions

Excessive Engine Oil Consumption

Symptoms

The driver may notice rapidly falling engine oil levels, frequent oil top-ups, blue exhaust smoke, carbon deposits, or oil contamination on the spark plugs.

Possible Cause

Worn, stuck, or damaged oil-control rings may no longer remove excess oil from the cylinder walls effectively. Oil can then enter the combustion chamber and burn with the air-fuel mixture.

Solution

Perform an engine diagnosis before replacing the piston rings. Check cylinder compression, leak-down results, cylinder-wall condition, piston grooves, PCV system, valve-stem seals, and external oil leakage.

If piston-ring wear or sticking is confirmed, inspect the complete piston and cylinder assembly before installing a new 23040-2G200 ring set.

Low Cylinder Compression

Symptoms

Possible symptoms include:

• Difficult engine starting

• Reduced acceleration

• Rough idle

• Poor engine power

• Increased fuel consumption

• Uneven cylinder performance

Possible Cause

Worn compression rings can allow combustion gases to escape between the piston and cylinder wall instead of maintaining pressure inside the combustion chamber.

Solution

Carry out a compression test and cylinder leak-down test.

If excessive leakage is detected through the piston/ring area, inspect the rings, piston ring grooves, pistons, and cylinders.

Excessive Blow-By

Symptoms

Excessive crankcase pressure, oil vapor, oil pushed through seals, or strong gas flow from the crankcase ventilation system can indicate excessive blow-by.

Possible Cause

The compression rings may no longer maintain an effective seal between the piston and cylinder wall.

Solution

Check engine compression and leak-down performance. Inspect cylinder bore wear and measure the piston and ring clearances before replacing components.

Carbon-Stuck Piston Rings

Symptoms

• Increasing oil consumption

• Reduced compression

• Blue smoke

• Poor engine response

• Increased crankcase pressure

Possible Cause

Carbon and degraded engine oil deposits can accumulate around the piston ring grooves, preventing the rings from moving freely.

Solution

During overhaul, remove the piston assemblies and inspect the ring grooves carefully.

Clean the piston grooves correctly and replace damaged or heavily contaminated rings.

The underlying cause of excessive carbon buildup should also be corrected.

Worn or Scored Cylinder Walls

Installing new piston rings alone may not solve the problem if the cylinders are already severely worn.

Possible Problems

• Cylinder taper

• Out-of-round cylinder

• Deep vertical scoring

• Excessive bore wear

• Poor cylinder surface finish

Solution

Measure the cylinders with suitable precision equipment.

Because 23040-2G200 is an STD-size piston ring set, it should only be used when the cylinder dimensions remain suitable for the standard-size specification.

If the cylinders have been machined oversize, the corresponding oversize ring specification must be selected instead.

Incorrect Piston Ring End Gap

Every piston ring requires a specified clearance between its two ends when installed inside the cylinder.

If the gap is too small: thermal expansion may cause the ring ends to contact each other, potentially resulting in cylinder scoring, ring breakage, or piston damage.

If the gap is too large: excessive combustion gas leakage may occur, reducing sealing efficiency.

Solution

Measure the ring end gap inside the corresponding cylinder before final engine assembly and use the service specification for the exact engine.

Do not use an unverified universal end-gap value.

Incorrect Installation Direction

Piston rings may have specific:

• Upper and lower surfaces

• Ring groove positions

• Profiles

• Installation markings

Incorrect installation can lead to immediate oil consumption or poor cylinder sealing.

Solution

Follow the ring markings and corresponding engine service procedure. Use a piston-ring expander and proper ring compressor during installation.

Installation Recommendations

Piston ring replacement is an engine-overhaul procedure and professional installation is recommended.

Before installing 23040-2G200:

1. Confirm OE number 23040-2G200.

2. Verify the VIN and engine code.

3. Confirm that STD-size rings are correct for the engine.

4. Remove and inspect the pistons.

5. Clean the piston ring grooves.

6. Measure cylinder bore diameter.

7. Check cylinder taper and out-of-round.

8. Inspect cylinder walls for scoring.

9. Measure piston-ring end gap.

10. Check ring-to-groove clearance.

11. Install every ring in the correct groove and direction.

12. Lubricate components with clean engine oil during assembly.

13. Use the proper ring compressor to reinstall the piston.

14. Replace related gaskets and seals when necessary.

15. Refill the correct engine oil and coolant.

16. Check compression and engine operation after repair.

KINGMAY Service & Supply Advantages

24-Month Warranty

KINGMAY provides a 24-month warranty for supported replacement auto parts, giving distributors, repair shops, and wholesale buyers greater confidence in long-term cooperation.

Warranty terms should be confirmed against the specific order, product batch, and agreed sales contract.

Factory-Direct Supply Advantage

KINGMAY works directly with qualified Chinese manufacturing resources and factory-side supply chains, reducing unnecessary intermediary costs and providing competitive B2B pricing.

KINGMAY's published sourcing policy describes this as factory-integrated sourcing, with production-side pricing and quality-control coordination rather than claiming that KINGMAY itself is a Korean OEM manufacturer. 

Professional Quality Control

KINGMAY performs dimensional and quality inspections before shipment and can provide material certification and batch-traceability information on applicable products.

The company's published quality process includes dimensional checks, pre-shipment verification, and SGS/TÜV material documentation upon request for supported product lines.

Samples Available Before Bulk Orders

New customers can order or request a sample first to inspect:

• Product appearance

• Fitment

• Dimensions

• Packaging

• Overall quality

before confirming a larger wholesale order.

KINGMAY's published ordering process specifically supports sample approval before bulk production. 

Flexible & Faster Shipping

Orders are consolidated and dispatched from Guangzhou, China.

For urgent requirements, KINGMAY can arrange faster shipping options according to order quantity and destination, including express or air-freight solutions for suitable small orders.

KINGMAY's Guangzhou operation and consolidated shipment capability are documented on its company website. 

Guangzhou & China Port Shipping

KINGMAY is based in Guangzhou and regularly handles export shipments through Guangzhou Nansha Port. Depending on the customer's destination, shipment size, freight schedule, and Incoterms, arrangements can also be coordinated through other major Chinese ports where required.

The company's normal export channel uses Nansha Port, Guangzhou, with export documentation and consolidated shipment support. 

Available international trade arrangements can include:

FOB / CIF / Sea Freight / Air Freight / Express Delivery

depending on the order and destination.

Korean & Japanese Auto Parts Coverage

KINGMAY specializes in replacement parts for Korean and Japanese vehicles.

Its key coverage includes:

Korean Vehicles
Hyundai, Kia and related applications.

Japanese Vehicles
Toyota, Nissan, Honda and other supported applications.

KINGMAY's published product strategy specifically focuses on Japanese and Korean vehicle parts, with particular strength in Hyundai/Kia and expanded coverage for Toyota, Nissan and Honda.

OEM Number & VIN Matching Support

Customers who are unsure of compatibility can provide:

• VIN

• Chassis number

• OE number

• Vehicle model/year

• Engine code

• Photo of the original part

KINGMAY can assist with OE cross-reference and fitment verification before shipment, helping wholesale customers reduce incorrect orders. 

Why Choose KINGMAY 23040-2G200?

The KINGMAY 23040-2G200 STD Engine Piston Ring Set combines OE-reference fitment with professional B2B sourcing, inspection, and international shipping support.

For importers, auto-parts distributors, engine rebuilding companies, repair shops, and wholesale buyers, KINGMAY provides a complete purchasing solution from sample verification and part-number matching to bulk supply, QC, packaging, and export from Guangzhou.

With 24-month warranty support, factory-side sourcing, flexible sample orders, accelerated shipping options, Korean and Japanese vehicle coverage, and international logistics support, KINGMAY is positioned as a long-term automotive parts supply partner rather than simply a single-product seller.