1986+ Mercury 6/8/9.9/10/15HP 2-stroke Factory Service Manual, Page 194Get this manual
POWERHEAD
Set-Up and Test-Run Procedures
CAUTION
When engine is started, IMMEDIATELY check for fuel leaks and water leaksCheck for water pump operation by water being discharged from tell-tale1Following powerhead repairs, refer to Section 2C TimingSynchronizingAdjusting to perform set-up procedures2While test running engine, check powerhead assembly for leaks andor unusual noisesMake any repairs BEFORE returning engine to service
Break-In Procedure