1994 9.9HP Evinrude Suddenly Stops

[mikeschumann]

For the last year or two I have been having continuous problems with my 1994 9.9HP 2 stroke Evinrude motor. It works just fine for a while, and then suddenly quits. It will be running just fine at 1/2 to full speed and abruptly stops, just like you turned off the ignition.

I have taken it to two different mechanics 3 different times, who found nothing wrong. One time they replaced the power pack. Yesterday, when it died, we towed the pontoon back to the dock. The next morning, it started and ran just fine, and then about 20 minutes later abruptly died again.

Any ideas what might be wrong and how I can troubleshoot the problem? Unfortunately, I can't get anyone to come out to the lake to look at the motor when it is dead, so we are never going to figure this out if I don't diagnose it myself.

 

[Joe Reeves]

Is this a remote setup engine (control box, ignition switch, etc)... or a tiller engine, manually operated at the transom?
Is it electric start or just rope start?
Do you have a Dead Man's Kill (lanyard) switch setup?
I assume that regardless of any setup, it has a kill button on the engine?

 

[oldboat1]

sure sounds like a keyswitch or kill switch issue. Did the mechanics check that out?

 

[mikeschumann]

It's on a pontoon, so it has a remote control box setup.

 

[boobie]

Get a cheap spark tester at a parts house, set it at 7/16" air gap and see if you have spark when it quits.

 

[Joe Reeves]

It's on a pontoon, so it has a remote control box setup.

Understood..... When this failure occurs, or before if you wish... remove the black/yellow wire (kill circuit) from either the ignition switch or the powerpack, whichever is easiest to get at. If that cures the problem, you have a intermittent short within the ignition switch... OR... a conductance type short at some point in that black/yellow wire leading from the powerpack to the ignition switch.

Checking for a conductance type short is done simply by having the black/yellow wire connected to the powerpack... but removed from the ignition switch.