The spark plug gap for a Honda GCV160 is typically 0.028–0.031 inches (0.7–0.8 millimeters). This article explains the official spec, why it matters, and how to check and adjust the gap safely.
Official gap specification
The Honda GCV160 engine requires a spark plug gap of 0.028–0.031 inches (0.7–0.8 mm). Use a standard, quality spark plug from NGK or Denso that matches the engine’s heat range and thread size. Commonly used equivalents include NGK BPR5ES or BPR6ES, or their Denso equivalents. Always verify the exact plug type and gap for your specific model before installation.
How to check and adjust the gap
To inspect and adjust the gap on a GCV160, follow these steps:
- Safety first: disconnect the spark plug cap, remove the spark plug with a spark plug wrench, and set the plug and tool on a non-conductive surface.
- Check the current gap with a feeler gauge or a dedicated spark plug gap tool.
- If the gap is outside the 0.028–0.031 in (0.7–0.8 mm) range, carefully adjust the ground electrode. Gently bend the electrode toward or away from the center to reach the specified gap in small increments, then re-measure.
- If the plug cannot be adjusted to spec or shows wear, fouling, or damage, replace it with a new plug that matches the engine’s requirements.
- Reinstall the plug, reconnect the spark plug cap, and verify engine operation.
Following these steps helps ensure reliable starts and smooth operation. Incorrect gaps can lead to hard starting, misfires, or reduced efficiency.
Why the gap matters
The spark plug gap influences ignition quality and combustion in the GCV160. A gap that’s too wide can cause misfires and hard starts; one that’s too narrow can limit flame kernel development and reduce efficiency. Maintaining the correct gap—0.7–0.8 mm (0.028–0.031 in)—helps optimize performance under typical lawn-care loads.
Summary
The Honda GCV160 calls for a spark plug gap of 0.028–0.031 inches (0.7–0.8 mm). Use a compatible plug, verify the gap before installation, and adjust carefully if needed. Regularly checking and maintaining this gap supports reliable starting and steady engine performance.