Husqvarna 503235401 NGK CMR6A Resistor Spark Plug – Genuine OEM Replacement Spark Plug

Part Number: 503235401
Category: Chainsaw, Trimmer & Outdoor Power Equipment Ignition Parts
Type: NGK CMR6A Resistor Spark Plug – Genuine OEM Replacement Spark Plug

The Husqvarna 503235401 NGK CMR6A Resistor Spark Plug is a genuine OEM replacement ignition component designed for select Husqvarna chainsaws, string trimmers, brushcutters, hedge trimmers, blowers, and other gas-powered outdoor equipment. Installed in the engine cylinder head, the spark plug produces the electrical spark required to ignite the compressed air-fuel mixture during starting and normal engine operation.

Product Specifications

• Part Number: 503235401
• Manufacturer: Husqvarna
• Spark Plug Manufacturer: NGK
• Spark Plug Model: CMR6A
• Product Type: Spark Plug
• Component Type: Engine Ignition / Tune-Up Component
• Plug Type: Resistor Spark Plug
• NGK Heat Range: 6
• Thread Diameter: 10 mm
• Thread Pitch: 1.0 mm
• Thread Specification: M10 x 1.0
• Reach: 12.7 mm (1/2")
• Hex Size: 16 mm (5/8")
• Function: Ignites the Compressed Air-Fuel Mixture
• System: Engine Ignition / Combustion System
• Application: Chainsaw / Trimmer / Brushcutter / Hedge Trimmer / Blower
• Compatible Brand: Husqvarna
• Replacement Type: Direct OEM Replacement
• OEM Status: Genuine Husqvarna OEM Part
• Condition: New
• Quantity: 1 Spark Plug
• Part Number Reference: 503235401

Features & Benefits

• Genuine Husqvarna OEM replacement spark plug
• Factory-specified NGK CMR6A configuration
• Resistor-type spark plug design
• M10 x 1.0 thread specification
• Designed for compatible Husqvarna gas-powered engines
• Produces the electrical spark required for combustion
• Helps support reliable cold and warm engine starting
• Supports smooth idle and consistent engine operation
• Helps maintain efficient combustion when properly serviced
• Suitable for routine engine tune-ups and preventive maintenance
• Manufactured to meet the applicable original equipment requirements
• Compact configuration suitable for many small two-stroke engines
• Helps restore ignition performance when replacing a worn or fouled plug
• Ideal replacement for fouled, worn, carbon-coated, corroded, cracked, or damaged spark plugs
• Direct replacement for equipment requiring 503235401
• Genuine OEM replacement rather than an unspecified universal spark plug

Applications

The Husqvarna 503235401 NGK CMR6A Spark Plug is used across numerous Husqvarna gas-powered equipment platforms.

Applications may include:

• Husqvarna chainsaws
• Husqvarna string trimmers
• Husqvarna brushcutters
• Husqvarna clearing saws
• Husqvarna hedge trimmers
• Husqvarna handheld blowers
• Husqvarna backpack blowers
• Husqvarna pole saws
• Select Husqvarna professional equipment
• Two-stroke engine applications
• Engine tune-up and maintenance
• Ignition-system repair
• Equipment specifying NGK CMR6A
• OEM replacement applications requiring 503235401

Because spark plug requirements can vary by engine, model, market, and production revision, always verify the specified plug for the exact equipment before ordering.

Important Notes

• Verify compatibility with your specific Husqvarna model, product number, serial number, engine configuration, and production revision before ordering.
• 503235401 corresponds to the NGK CMR6A resistor spark plug.
• Match 503235401 / CMR6A with your equipment's illustrated parts diagram, owner's manual, or OEM service documentation.
• The “R” in CMR6A denotes a resistor-type spark plug.
• Do not confuse CMR6A with BPMR7A or other common Husqvarna spark plugs. They have different physical and operating specifications and should not be substituted unless specifically approved for the equipment.
• Do not select a replacement spark plug based solely on thread diameter or physical appearance. Thread pitch, reach, heat range, resistor configuration, electrode design, and engine requirements must also match.
• A worn or fouled spark plug may contribute to hard starting, intermittent ignition, misfiring, poor acceleration, unstable idle, reduced power, or failure to start.
• Similar symptoms can also result from carburetor problems, stale fuel, clogged filters, damaged ignition components, air leaks, or low engine compression.
• Inspect the spark plug boot, connector, ignition lead, ignition module, and cylinder-head threads when replacing the plug.
• Clean dirt and debris from around the spark plug before removal to help prevent contaminants from entering the cylinder.
• Allow the engine to cool before removing or installing the spark plug.
• Start the replacement spark plug by hand whenever possible to reduce the risk of cross-threading the cylinder head.
• Do not overtighten the spark plug. Follow the torque specification specified for your exact Husqvarna equipment.
• Check and adjust the electrode gap according to the specification for the exact equipment model rather than assuming one gap applies to every Husqvarna application using CMR6A.
• Replace a plug with cracked porcelain, damaged threads, excessive electrode wear, severe deposits, or other physical damage.
• Abnormal spark plug deposits or coloration can indicate an underlying fuel-mixture, combustion, ignition, or engine condition that should be diagnosed separately.
• This listing is for one Husqvarna 503235401 NGK CMR6A Resistor Spark Plug only unless otherwise specified. Spark plug boots, connectors, ignition leads, ignition modules, and other tune-up components are sold separately.
• Match part number 503235401 / NGK CMR6A with your equipment's OEM documentation before ordering to ensure proper fitment.