It depends upon the engine. Engines with higher compression require a narrower gap. If this is for a marine application (IE:outboard motor) 0.030 is the gap required for most, but you should double check.
Champion L77-JC4 plug set to .030in.
The 1979 model Johnson 9.9hp uses a Champion L77-JC4 spark plug.
The Q indicates radio noise suppression.
The Husqvarna L77 chainsaw features a 3.3 horsepower engine with a displacement of 77 cc, making it suitable for heavy-duty cutting tasks. It has a bar length that typically ranges from 20 to 28 inches, allowing for versatility in cutting large trees and logs. Additionally, the chainsaw is equipped with an automatic oiling system for chain lubrication and a lightweight design to enhance maneuverability. Its ergonomic handle provides comfort during extended use, making it a reliable choice for both professional and recreational users.