Re: Is this electric shift switch reliable?
the F and R coils in the lower unit, as their name implies, are coils of wire. When you turn off the power to any coil of wire (i.e. electromagnet) , the magnetic field collapses. This collapse induces a large "outrush" of current in the wire. The opening of the switch contacts in concert with this induced high current flow causes an arc or spark at the switch contacts. This is the exact way an ignition coil makes sparks at your spark plugs. But this is undesirable obviously in a shifter.
That spark burns the metal switch contacts and blackens them with carbon. It can melt the metal.
All that said, the root issue here is that OMC never saw fit to use capacitors or diodes or any other such device to suppress this arcing and sparking. Most any modern system with electromagnetism (e.g. your car's Air conditioning compressor clutch) uses a diode to supress the arc at the relay.
The bottom line: No switch is going to survive and be reliable for as long as it should due to OMC's design flaw. I would plan on a 3 to 5 year replacement on a frequently used boat and plan for failure at sea to be possible. (i.e. carry a spare or be ready to short some wires to obtain Forward gear)
The reason the dash mounting of a $35 drum switch from home depot is often suggested, is two fold.
1. It's $35
2. It can be disassembled and contacts cleaned with emery cloth or other abrasive to remove the carbon
Some problems with a "dash mounted" switch:
1. someone can shift at high rpm and destroy the lower unit
2. non standard controls
3. you need to choose a decent switch and field engineer the install
