On the lake in my area you can have 6' to 8 ' waves during a windy day.----Then if the wind dies down the waves keep rolling along and it takes the swell a few hours to die down.
The service bulletin came out in 1994 to deal with the 3 cylinder 56 cube motors.------Many folks have gone overboard and applied this to every outboard !!
I know of a owner who used to run his 150 HP Mercury V-6 in his driveway.--Loved the sound of it.-----He was told repeatedly to use garden hose and muffs.----His reply was " I am only running it for 20 seconds or so , it won't over heat "
Timing on these motors generally does not change.-----Adjusting and hoping it will run better may well lead to expensive damage.----Best to do some trouble shooting to find out what is wrong.