Intermittant running of 50 HP Force

BPShooter

Recruit
Joined
Apr 29, 2012
Messages
3
Hello - I am new to this forum but a longtime boat owner. Unfortunately I have to start my first thread with a tech question and I'll try to keep it short and direct. Last summer my 50 HP Force died - no spark from either coil but power everywhere else. I got it in the shop a couple weeks ago to work on it and while I happened to be holding a coil wire I spun the motor and got a 'poke' - Ok now I have spark (again) but I noticed as I stuck a screwdriver into the cap and held it close to the block the spark became progressively weaker. I pulled the cap off the wire and discovered the spring connector for the spark plug was heavily corroded and making poor connection. I pulled it out, stripped the wire and spun the motor and now had a bright blue spark. I changed the connectors on both wires and the motor started right up but had a miss and I heard a 'snapping' sound which turned out to be the top coil 'leaking' to ground. I took the coil out of the bracket to isolate it and the motor ran with out a miss but I would get a shock when I touched the coil so I replaced the coil. The motor ran fine with the new coil, I took it out to a local reservoir and it ran perfectly. I thought I had it fixed but yesterday I was getting ready to take it out I decided to give it a test start and nothing again - no fire. I have copies of the diag procedures for the Force and did some of them with no change. I have checked all wires for broken or open connections and everything looks good. I do not see any evidence of hot wires as there is nothing burnt and all have normal coloration. Initially I thought it might be the switch box (as it is called) but then I discovered the plug wire problem and had good spark so I dismissed the switch box as the problem. The frustrating part of this is the intermittent problem - I mean when it ran last week it ran fine and then nothing again. Now, one observation I need to mention - When the key is 'on' I do not detect any power at any of the terminals of the bus bar on the switch box/coil mounting plate where all the connections are made. Shouldn't there be power to the switch box when the ignition switch is on? That is it - I'll stop here. Any help will be appreciated. Thanks.

Ed Miller
LaPine, OR
 

BPShooter

Recruit
Joined
Apr 29, 2012
Messages
3
Re: Intermittant running of 50 HP Force

One more question about this - Is it possible for the switch box to operate intermittently or are they a go/no-go part?
 

BPShooter

Recruit
Joined
Apr 29, 2012
Messages
3
Re: Intermittant running of 50 HP Force

Would the next course of action be to remove the flywheel and examine the stator & related components? Any help will be appreciated with this.
 
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