# B7S NGK Standard Spark Plug | Genuine NGK Spark Plug

## 🔧 Product Description

**NGK Standard Spark Plug – Part Number: B7S**

Spark plugs are a critical engine component, providing the spark that ignites the air-fuel mixture that drives an engine. NGK spark plugs feature trivalent plating – a silver/chrome-coloured finish on the threads – for corrosion resistance against moisture and chemicals, and are designed to meet or exceed OE standards.

## ⚙️ Key Features

-   Standard nickel centre electrode
-   Trivalent metal plating provides superior anti-corrosion and anti-seizing properties
-   Corrugated ribs reduce the risk of flashover
-   Pure alumina silicate ceramic insulator, providing superior strength and better heat transfer
-   Copper core aids in heat removal
-   Triple seals prevent leakage

## 📏 Specifications

-   NGK stock number: 3710
-   Thread: 14 mm
-   Reach: 9.5 mm (3/8 in)
-   Hex: 20.8 mm (13/16 in)
-   Seat: Gasket

## 🚘 Application

Listed in NGK's application charts for marine, motorcycle, ATV and snowmobile equipment and lawn, garden and commercial equipment. The gap is not the same on all of them – the chart lists between 0.5 mm and 1.0 mm depending on the engine, so check the line for yours.

-   Mercruiser 225 (8 CYL GM SMALL BLOCK) – Inboard Engine
-   Mercruiser 225 (8 CYL GM SMALL BLOCK, TO) – Inboard Engine
-   Mercruiser 250 (8 CYL GM SMALL BLOCK, 2317201-) – Inboard Engine
-   Mercruiser 250 (8 CYL GM SMALL BLOCK, TO) – Inboard Engine
-   Mercruiser 270 (8 CYL GM SMALL BLOCK, GASKET SEAT) – Inboard Engine
-   Mercury 1000 (100 HP, 1964-1962) – Outboard Engine
-   Mercury 900 (90 HP, 1965) – Outboard Engine
-   Mercury 850 (85 HP, 1964-1962) – Outboard Engine
-   Mercury 800 (80 HP, 1961-1960) – Outboard Engine
-   Mercury 650 (65 HP, 1966-1963) – Outboard Engine
-   Mercury 500 (50 HP, 1966-1961) – Outboard Engine
-   Mercury 350 (35 HP, 1966-1961) – Outboard Engine
-   Hodaka ACE 90 (90) – Motorcycle
-   O.M.C. - Snowmobile Engines M227 (440)
-   Bolens SWIFTY 3014 – Chainsaw
-   Bolens THRIFTY 3010 – Chainsaw
-   Poulan Pro 10, 30 – Chainsaw
-   Onan CCK (NATURAL GAS) – Lighting Plants and Generator
-   Tanaka REG-800, REG-1000 – Lighting Plants and Generator
-   Trimmer 4500 – Outdoor Power Equipment
-   Power Blower JNBL-33, JNBL-33A – Outdoor Power Equipment
-   Power Blower ULNBL-3 – Outdoor Power Equipment
-   Vandermolen 88 – Outdoor Power Equipment
-   Kawasaki KT15M (1.3HP) – Power Equipment Engine
-   Mitsubishi T280 (2.8HP) – Power Equipment Engine

That is the 25 most common of 39 applications NGK's charts list for this plug – ask us to check yours.

## 🔄 Supersession & Cross Reference

NGK's cross-reference tables list this plug against these part numbers.

-   Champion: 825, 825C, 825S, J4, J4C, J4J, J5, UJ4J and 2 more
-   ACDelco: C41, M42K, MC44, S42, S42\*, SB41
-   Motorcraft: A2, A2C, A2X, AT2, AZ2
-   DENSO: 4027, W22S, W22S-U
-   Autolite: 3013, 313
-   Bosch: 7534, W5EC
-   Accel: 123

## 📦 Condition

-   Brand new genuine product
-   Supplied in original packaging

## Details

- **Price:** 11.0 AUD
- **Vendor:** NGK
- **Type:** Ignition & Controls

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 11.00 AUD | In stock |

## Images

- B7S NGK spark plug
- B7S NGK spark plug firing end

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/b7s-ngk-standard-spark-plug-genuine-ngk-spark-plug)
> Updated: 2026-09-03