2006 SD Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 86Get this manual
ELECTRICAL ELECTRIC STARTER SYSTEM Brushes Brush Spring
Check the length of each brush Standard: 0.61 in(15.5 mm) Service limit: 0.37 in(9.5 mm) If brushes are worn to service limit, replace brushes
Inspect brush spring for wear, damage, or other abnormal conditionsCheck the brush spring tension Standard: 3.3 to 4.0 lb(15 to 18 N) Replace if necessary1Brush