Both engines won’t start

[Woodsy]

I am on a roll with boat issues. The fluttering rpm issue of yesterday seems to have resolved itself. Had no problem with that today. However….
We spent about 2 hours on the water water skiing and zup boarding. Great time, all was good. Started and stopped the motors many times. Last ride behind the boat was finished, stowed away the gear went to start the motors, the port motor started for a second then stopped. Neither motor would start. Full power to dash, no error codes. So I did the following:
- cycled the throttles, made sure in neutral.
- disengaged and reseated the safety kill lanyard.
- pressed down both kill switches in the clean out hatch and turned the keys.
- tried to jump the battery with the noco battery booster
- turned the battery switch off and back on.
No luck. So I called a friend to get a tow. While waiting, I figured we might as well try once more. Turned the battery on again, turned over the motors, and they both started! Drove back to the launch in no wake mode without issue. All seemed right. Once at the ramp, I turned off the motors, and once again neither engine would start. Walked the boat on the trailer, and once back at the house 15 minutes later, tried both motors again and neither will turn over.

What do you think all my wise friends on this forum?

 

[FSH 210 Sport]

Did you check the battery connections, and the connection on the battery switches?

Seems like a place to start since it’s affecting both engines.

 

[Woodsy]

The battery terminals are tight. Checked those. But I will add checking the switch connections to my todo list.

 

[FSH 210 Sport]

It sounds like an intermittent electrical problem.. there have been several issues caused by bad grounds as well.

 

[Dixemon]

Hows your fuel level? Battery state of charge?

 

[Woodsy]

Found some boat time today. Fixed the problem.

It was simple, removed all the negative leads off the battery, sand papered them all clean, along with the battery post, put them back on the battery and cranked it on tight.

Nothing better than a quick easy fix. A little bit surprised how the helm ground was good and the motors weren’t when they all shared the same post.

 

[Judge]

Bad grounds are the #1 root cause of issues like this on any vehicle. We have all had our fair share whether we knew it or not at the time.

After a ground that drove me nuts on a snowmobile many years ago, I came with a very quick and easy test to check for a bad ground anytime electrical issues with staring pop up unexpectedly.

All you need is the negative lead from a set of jumper cables.

Take one of the alligator clamps and connect one end of the negative jumper cable directly to the (-) post of the battery. Take the other end and clamp it somewhere onto the engine block. Then try to start the engine(s).

If it fires up, you can then start looking at the grounding cables at the battery, the engine block and all other grounding points.