Spark plug M117 M116 as an alternative to the Bosch W9DC0 – Mercedes R107 380SL 560SL USA

Description

NGK BP5ES spark plug – affordable alternative to Bosch WR9DC / WR9DC0 – Mercedes M116 and M117 V8 engines

The NGK BP5ES is a high-quality spark plug and an excellent alternative to the Bosch WR9DC and WR9DC0 Spark plugs that were originally used in various Mercedes M116 and M117 engines. This spark plug is widely used in Mercedes models with a lower compression ratio, including various export versions outside Europe.

The original Bosch WR9DC spark plugs from the former German production are now hardly available anymore. Good Bosch NOS spark plugs are becoming increasingly scarce, causing prices to rise sharply. That is why more and more Mercedes enthusiasts and specialists are opting for the NGK BP5ES as a reliable and affordable alternative.

We regularly use these spark plugs in various Mercedes V8 engines, and the experiences are excellent. The NGK BP5ES is known for its reliable ignition, stable engine operation, and excellent price-performance ratio.

Suitable for, among others

• Mercedes R107 380 SL
• Mercedes R107 560 SL (USA version)

• Mercedes W126 380 SE / SEL
• Mercedes W126 560 SEL (USA version)

• Various Mercedes models with M116 and M117 engines with a lower compression ratio.

• Various export versions outside Europe.

Specifications

1. Brand: NGK.
2. Type: BP5ES.
3. Thread size: M14 × 1.25.
4. Thread length: 19.0 mm.
5. Wrench size: 20.8 mm.
6. Seal: flat sealing ring.
7. Center electrode: nickel.
8. Number of ground electrodes: 1.
9. SAE connection: screw-off.
10. Interference suppression: not suppressed.
11. Electrodeposition: 3.0 mm.
12. Alternative to Mercedes A0031591003 / 003159100326 / 0031591003.
13. Price is per piece.

Advantages

1. Affordable alternative to Bosch WR9DC and WR9DC0.
2. Suitable for classic Mercedes V8 engines with a lower compression ratio.
3. Reliable cold start and stable engine operation.
4. Good availability compared to original Bosch spark plugs.
5. Excellent value for money.

Important

Before installation, always check that the prescribed heat number matches your engine specifications. In particular, different spark plug types may be prescribed for European and American versions of the M116 and M117 engines.

In case of doubt, we recommend checking the original Mercedes part number, engine number, or the engine compression ratio.

Always carefully inspect new spark plugs for transport or fall damage before installation. A dent or damage to the packaging may indicate that the spark plug has been hit hard. As a result, the ceramic insulation part may contain invisible hairline cracks.

Damaged ceramic can come loose during use and enter the combustion chamber, potentially resulting in serious engine damage. Therefore, install only spark plugs with completely undamaged ceramic.

Always check the spark plug electrode gap before installation. For most Mercedes M116 and M117 engines, an electrode gap of 0.8 mm recommended. Check each spark plug with a feeler gauge and correct the gap if necessary according to Mercedes factory specifications.

We recommend replacing spark plugs preventively every 8 years or 30,000 kilometers to replace, depending on which is reached first. Even in vehicles that are driven infrequently, the electrodes and insulation material can deteriorate due to aging, which can lead to a weaker spark, rough engine operation, higher fuel consumption, and reduced cold starting.

Always check before purchase and installation whether the part is suitable and equivalent based on photos, description, and specifications; installed or used parts cannot be returned.