Osculati 47.558.59 – NGK LFR4AE Marine Spark Plug
The NGK LFR4AE (Osculati 47.558.59) is a premium resistor-type spark plug developed for 4-stroke marine engines that require extended ignition stability under high-performance or high-compression operating conditions. With its long 19 mm reach, recessed ground electrode, and cold heat range (4), this plug is ideal for engines exposed to full-throttle use, prolonged load, or extreme combustion pressures.
Key Features:
- Cold heat range (4) designed for high-output marine applications
- Recessed ground electrode enhances anti-fouling and improves flame propagation
- Built-in resistor for suppression of radio frequency interference (RFI)
- Long 19 mm reach ensures proper fitment in modern cylinder heads
- Corrosion-resistant construction ideal for harsh marine environments
Technical Specifications:
| Attribute | Value |
|---|---|
| Model | NGK LFR4AE |
| Osculati Code | 47.558.59 |
| Thread Diameter | M14 × 1.25 mm |
| Reach | 19 mm |
| Hex Size | 16 mm |
| Heat Range | 4 (cold) |
| Gap | 0.9 mm |
| Electrode Type | Standard with recessed ground electrode |
| Resistor | Yes |
Manufacturer Compatibility:
- Yamaha
- Mercury
- Mariner
- Suzuki
- Tohatsu
- Selva
- Honda
Cross Reference:
| Brand | Model |
|---|---|
| NGK | LFR4AE |
| Champion | – |
The NGK LFR4AE is engineered for outboards operating under sustained full-load conditions. Its recessed electrode supports cleaner combustion and reduced pre-ignition risk, while the cold heat rating ensures thermal stability. Ideal for marine professionals requiring long-life plugs with OEM-level reliability and protection against misfire and fouling.
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