Replaced Ignition coil(s)

[capecodcruiser]

This is more of a post for anyone having engine issues. My boat hadn't been in for 6 years. I put it in this year after doing much re-commissioning. Boat ran great initially. Once I was comfortable with it idling and cruising at low RPM, I started to wind it up. Would run fine at my comfortable 36-4000K RPM for about 10 min than the port engine would cough and stumble and not get above 17-2000RPM and would eventually die. Looked at fuel system, was fine. Started to think of heat related symptoms and thought of ignition coil. I swapped the coils between engines. Voila, the problem followed the coil. Easy swap with new coil. Thought problem gone. Headed out this past weekend and ran perfect for about 1/2 hour. Now the engine with the "old" swapped coil started to act up again right as I was about to go into a channel that is the most dangerous on the east coast! I was able to nurse it through and make it to my destination. Engine was doing the exact same thing as before. I bought another coil, changed it out and again, voila. Ran 1.5 hrs at 3600RPM all the way home on Sunday. Have never had a coil go bad on me in all my years of working on engines of all kinds. So, in 2 weeks I have had 2 go bad. Hope this helps someone in the future. I could have chased 10 other potential issues, but wanted to start with the easy solutions first. Happy boating!

 

[Benhole]

I was having some issues with the starboard engine, it was turning over but not firing up. I changed a battery out, engine still didn’t fire. Swapped out the coil for another used coil and the engine fired right up. Thought I was in the clear until about 15 minutes later as I was heading out to the bay, the starboard engine died. Motored most of the way in with the port engine but was able to get the starboard engine going again right before docking. A couple days later, started up the engines, both fired no problem. started heading down alleyway and two minutes later, starboard cuts out again. Is it possible that I have two bad coils as well??

 

[capecodcruiser]

I was having some issues with the starboard engine, it was turning over but not firing up. I changed a battery out, engine still didn’t fire. Swapped out the coil for another used coil and the engine fired right up. Thought I was in the clear until about 15 minutes later as I was heading out to the bay, the starboard engine died. Motored most of the way in with the port engine but was able to get the starboard engine going again right before docking. A couple days later, started up the engines, both fired no problem. started heading down alleyway and two minutes later, starboard cuts out again. Is it possible that I have two bad coils as well??

Your symptoms don't point too coil. You need to look at your fuel system as well. Also the ignition module in the distributor. You need to do more diagnostics.

 

[Benhole]

Thanks for the feedback. I originally was thinking clogged injectors or fuel pump issue but when I changed out the coil and the engine finally started it was hard to think otherwise. But I think you’re right, has to be more than just the coil. Btw- the coil is part of an ignition module that I swapped out.

 

[Mknupp]

I had that same problem, although it was intermittent and the would not start,long story short,ignition modules in distributor were bad. Replaced both, problem solved

 

[Benhole]

I had that same problem, although it was intermittent and the would not start,long story short,ignition modules in distributor were bad. Replaced both, problem solved

Interesting thanks for the reply. Doesn't look like my engines have ignitions in the distributors. Just spoke with the tech this morning and they are replacing the ignition module/coil again. Hoping this will solve the problem. Otherwise, there has got to be something else electrical. If not, going to have to start looking at fuel system.