Troubleshooting Evinrude 70

[74Cobia]

Hello, I need help. I have a 90s model Evinrude 75, have run 70 hp motors for years. After 3 years of troublefree operation, the motor simply wouldn't start one day. The next day it started no problem. I was able to drive it back to the ramp as if the issue never happened. I immediately thought "power pack". I ordered one, installed, and the motor ran with one issue, no spark to the bottom cylinder. I rotated the coils, the problem stayed with the bottom cylinder. I even tried reinstalling the old power pack, and the problem remained. No spark to the bottom cylinder. I have cleaned all the grounds and used new wiring concerning the bottom cylinder but no change. I was under the impression that the power pack received power from one lead, and then sent out power to the three coils. Any suggestions would be appreciated.

 

[Joe Reeves]

Re: Troubleshooting Evinrude 70

If that engine has the round type rubber connector plugs, check to make sure that the pins or sockets haven't been pushed back somewhat within the plug(s) which would result is a poor or non existent connection.

Also make sure that a wire has not broken off of a pin or socket...... I've seen this many times where the wire would still be stuck within the rubber socket BUT with no connection to the pin or socket.

 

[74Cobia]

Re: Troubleshooting Evinrude 70

Thanks, that is kind of where I was thinking. So what I'm hearing is I'm probably good from the plugs, to the coils, to the power pack, and I may have a commection issue elsewhere with the 2 rubber connector boots/pins? I just assumed that if the pack was sending spark to 2 cylinders that it was getting power to distribute to all three.

 

[Joe Reeves]

Re: Troubleshooting Evinrude 70

The powerpack derives its power/voltage from the stator. The timing sensors regulates which coil is fired at any particular time. My first stop would be at the rubber plug connector leading from the timing sensors under the flywheel to the powerpack.