1972 evinrude wont stay in gear.

[Donnis Reese]

I have a 1972 evinrude 65 hp motor with the hydro-electric shift mechanism It pops in and out of gear at anything more than idle speed. it only does this in forward (not reverse) It is designed to default into forward in case of trouble with the solonoids so I disconnected them to eliminate them as a problem source but it still pops in and out of gear. please help.<br /><br />Also I am in need of a diagram and disassembly instructions for this lower unit if anyone has them Thanks in advance