Impact of Replacing B6HS with B7HS Spark Plugs in a Makita EW220R 2

When considering the installation of a B7HS spark plug in place of a B6HS in a Makita EW220R 2, it's important to understand the implications of such a change. This article explores how the heat range, engine performance, and compatibility of these spark plugs might affect the overall function of the Makita EW220R 2.

Heat Range

The heat range of a spark plug is crucial for the proper operation of the engine. The B6HS spark plug has a heat range designed to operate effectively within the temperature range of the engine, ensuring optimal performance under normal operating conditions. In contrast, the B7HS is a colder plug that can dissipate heat more effectively.

Improved Performance in High-Load Conditions

Installing a B7HS spark plug instead of a B6HS can result in:

Better performance during high-stress environments

Reduced risk of pre-ignition and engine knocking

Potential for Fouling

However, if the engine operates at lower temperatures or under lighter loads, the B7HS may not reach its optimal operating temperature. This can lead to issues such as:

Fouling

Misfires

In these cases, the engine may not perform as intended, potentially leading to inefficient combustion and reduced engine longevity.

Engine Performance

Changing the heat range of the spark plug can have a significant impact on the engine's performance:

Altered Ignition Characteristics

The colder B7HS spark plug may ignite the air-fuel mixture differently, potentially affecting:

Performance

Fuel efficiency

Emissions

Starting Issues

An engine running with a colder plug might have difficulty starting or running smoothly, especially in colder conditions. This could result in:

Lower starting torque

Unstable engine operation

Compatibility

While both spark plugs may fit physically, the difference in heat range means that the engine may not perform as intended. It is generally advisable to use the manufacturer-recommended spark plug, the B6HS, to ensure optimal performance and reliability.

It's also worth noting that the second digit in the spark plug model may not refer to the heat range but could instead indicate the threaded length. Therefore, it's crucial to double-check these specifications to ensure compatibility.

Conclusion

While it is possible to use a B7HS spark plug in place of a B6HS, it is not recommended unless you are experiencing specific issues that a colder plug would address. For the best results, stick with the manufacturer's specifications to ensure proper engine function and longevity.

If you suspect that carbon fouling might be an issue, the B7HS spark plug should address this problem and allow the pump to run smoothly.

It's always best to verify the specifications and consult with a professional to ensure that any changes to the spark plugs are appropriate for your specific situation.