Mercury outboard problem
I went down to the Little Su this morning to get the boat on the water and our 2 35HP Mercury outboards started okay and so I backed the boat off the trailer and parked it. After loading up, I attempted to restart the motors. One motor started fine - the other would not turn over. I popped the cover and manual turned the motor once and then after that the key would turn the motor with no problems, but the motor wouldn't start. Checked the plugs and they were getting spark. The gas was old so I was assuming bad gas/water in the line.
The motor eventually started and I idled it for a minute and then it stalled. Again I'm thinking "bad gas". When I turned the key to restart the motor, the motor started turning over but wouldn't start and then it wouldn't stop turning over. I physically took the key out, I put it in gear. Nothing would stop it from continually turning over.
The battery immediately started to boil so I quickly tried to get the wing nuts off of it to disconnect the motor. The battery had gotten so hot that my gloves actually caught on fire while trying to get the wing nuts off. I quickly stuck my hand in the river and went back to getting the motor disconnected from the battery.
I couldn't find any wires on the motor that may have gotten crossed. Do you think the motor was the problem or could it have been the remote throttle?
We ended up reconnecting the motor that was working fine to the battery and driving the boat back onto the trailer and called it a day. After getting home, I touched the cables to the bad motor to the battery and the engine immediately tried to turn - No key in the ignition.
Sounds like a stuck starter solenoid, for one thing.
The constant starting mode can be caused by a stuck starter solenoid, and in some designs, by a gummed up starter gear/shaft. I haven't ever worked on a Merc starter, so I can't tell you for sure.