Join Date: Apr 2006
Thanked 147 Times in 144 Posts
Rep Power: 11
Bill, what is the saying? You can never be rich enough, thin enough, or own enough proprietary crimping tools?
Chet, as Bill said about the battery. I've seen industry specs that starter motors throw 600VDC in spikes, and truck/bus starters up to 2000VDC in spikes, so actually you want to make sure the electronics (ALL of them) are not powered up at all when engaging that starter motor, or when shutting the engine down (when the alternator also throws spikes).
On cars that was traditionally not a problem as the "start" position on the ignition switch physically disconnected the other circuits long enough to miss the spikes (a matter of milliseconds, literally as the spring was turning the key back to the run position) but on boats, everything is usualy "on" and everything gets hit by the spikes, making spike protection more important--on everything.
And since spike protectors so wear out, most manufacturers don't spend money building them in, only to have owners complain "well how come it didn't last forever". Easy enough to buy a bagful and wire them into every electronic circuit, though. Or, at least, keep them isolated from the starter.