I have a 1998 Mercury 9.9 two-stroke. It has started giving me intermittent starting issues. Sometimes it has spark, sometimes it does not. I replace the electronica control box, no change. I replace the rectifier, no change. Replace ignition switch, no change. I checked / bypassed the kill switch, no change. Once I start it once and warm it up I can use the boat all day. It doesn’t matter if I’m trolling all day or stopping and starting it 20 times moving to different places. It works flawlessly once it starts for the first time.
Today I pulled the boat out into the driveway and put it in a bucket of water to try troubleshooting some more and it started instantly. I started it multiple times and ran it for a half an hour. It runs smooth quiet and flawless. It might just be in my head but it seems like with it doesn’t want to spark it is cold or cool out. It sat in the afternoon sun today, could that be why it started? Every time I think I find a problem by wiggling this or tapping on that because it decides to spark. I find out later that it just decided it wanted to spark.
As you can see this is driving me crazy. What else can cause intermittent spark and yet once it starts run all day and start dozens of times? I do not have a wiring diagram for the electrical system. If I did I would at least be able to start troubleshooting rather than throwing parts at it.
I am thankful for any experienced suggestions from someone who has dealt and fixed this issue before.
Today I pulled the boat out into the driveway and put it in a bucket of water to try troubleshooting some more and it started instantly. I started it multiple times and ran it for a half an hour. It runs smooth quiet and flawless. It might just be in my head but it seems like with it doesn’t want to spark it is cold or cool out. It sat in the afternoon sun today, could that be why it started? Every time I think I find a problem by wiggling this or tapping on that because it decides to spark. I find out later that it just decided it wanted to spark.
As you can see this is driving me crazy. What else can cause intermittent spark and yet once it starts run all day and start dozens of times? I do not have a wiring diagram for the electrical system. If I did I would at least be able to start troubleshooting rather than throwing parts at it.
I am thankful for any experienced suggestions from someone who has dealt and fixed this issue before.
