1978 Johnson 4HP outboards Service Manual, Page 56Get this manual

PROCEDURE

Check spark plugsRemove plugs and inspect for excessive carbon deposits
Plugs OKGo to step 7Plugs not OKGo to step 6
Check exhaust ports, cyl inders, and pistons Remove exhaust covers
Ports, cyl inders, pistons OKGo to step 7Not OKService powerheadSee pages 5-6 thru 5-29

Check engine for bindingDisconnect four wire connector and crank engi ne with rope

• ATV
• Jet Ski
• Outboard Motors
• Personal Watercraft
• Snowmobiles
• Stern Drives