Shifting problem with Tohatsu mfs 5.

Hello boatsengine. I am from Russia, and beforehand sorry about my english. So the problem is. Mercury 5 four stroke outboard (it also Tohatsu MFS5) 2012 year, cut of forward gear when changing loading conditions. As example, runing on waves, or faster stearing (rapidly rotating motor left or right). Boat fall of planing, motor roars, when speed significantly down, gear will engaged and boat will moving as before. No abnormal noises hear. This happening only on high load (full throttle or close conditions). What may be problem, what you think?

You may need a new prop. The rubber hub may be damaged.

Paul, One more question, if i may. How to work decompressors on Tohatsu camshaft, i mean operating principel?

It is a centrifical weight on the camshaft. Automatic. Engages above about 500 RPM for full compression.