I screwed up Boat will not start

[Shape2001]

2016 242x 100 hours
Had the boat out last weekend. Everything was perfect.

Left slip in a hurry and did not realize I left keys in the ignition and in ON position.

House/start battery switches were also on. Stay and house plugged into Noco. Stayed that way for 6 days.

This weekend batteries were dead. Shut off both battery switches and ignition and left on Noco. Waited for a few hours.

Turned on house. Put in key. Turned key and no boot sequence of connext system. Turned on start and house and connect did boot. Batteries were both reading 11.x V.

Engines both crank and come close to start but neither will fire. Tried to jump using portable jumper battery and using parallel switch. Getting powerful crank but no ignition.

checked lanyard and clean out kill switches. Engine will not crank with lanyard out or hatch open. With lanyard and hatch button pushed manually or with lid the engines do crank.

Charged again overnight. Reading 12.8V on each. Same issue. No connect boot of house. Strong crank but no start. I tried factory reset. I swapped batteries. I cleaned all terminals and connections. I checked all fuses I could find. Somewhere there is a failure in the system. Not seeing any error codes or warnings

I think everything is related to my inability to boot connext from house battery alone. I never needed my start battery on to boot connext system but now I do. There must be a relay or fuse or something zapped or triggered that is not allowing me to boot connext off house alone and also not allowing my boat to pass all the checks to allow engine to fire.

Any ideas to help solve this mystery much appreciated!

 

[Acard7]

Check all the fuses for sure. It might be worth pulling the batteries and just having them checked to make sure they are good still..

 

[Shape2001]

I checked the 3 fuses in the battery compartment and all the fuses in the two banks behind the motors on the transom. All looked good

 

[Bottom Bracket]

Gas tanks empty.

 

[Shape2001]

No the tank is close to full. Just filled last time I was out

 

[Bottom Bracket]

pull a spark plug, see if its wet.

 

[Neutron]

Make sure the lanyard is properly engaged. You will still crank but no fuel

 

[Oafy44]

it seems to me you’re pretty close…., still think your volts are about 1.5 too low. I would give it another day or two on the charger and wouldn’t be surprised if it works. I also think the NOCO has a few settings depending on the batteries status so it might take a little more time to repair them if it’s able to

 

[fubar79]

Did you check the electrolyte level? Constant draw could of drained the liquid level. I had that issue when my previous boat was in a slip when the auto bilge would constantly cycle every few minutes. If you are getting a strong crank, probably not your main issue, but worth checking for the longevity of your batteries.

 

[Shape2001]

Batteries both showing 13.7

 

[Shape2001]

I don’t see any warning or engine codes

 

[Shape2001]

I keep coming back to the fact nothing happens if I turn key with house battery switch ON only. It used to boot my system, turn on dash etc and now does nothing even when I swap the battery. For dash to boot I need both start and house ON. If house only or start only is on nothing happens when ignition key is moved to ON. Both must be on to get any dash response. I feel like it’s a computer issue and something is not receiving power it should or not able to communicate properly

 

[Dave burke]

I had a similar problem with my Connext. They are very sensitive to voltage so if your house battery is not around 12.5 V with no chargers connected, it could cause problems. And of course make sure the terminals are clean but I think you've done that.

As to the engines cranking but not firing, that's a head scratcher to me. The obvious things are the lanyard and the kill switches in the clean out ports. It sounds like you've checked all that.

If I were you, I'd turn the house battery switch off to make sure there's no possible interference there (shouldn't be but just in case). Then try again. If no start, pull a plug and see if you smell gas and make sure you have a spark.

How old is the gas? Could it be bad? Could water have gotten in

Just read your post again. What do you mean but the engines come close to start but won't fire.

Another thought is if you check the spark and it's strong, maybe buy a can of ether and see if the engines will fire. If so, it's a fuel problem. Maybe plugged fuel filter?

 

[Shape2001]

I cannot post a video but engines crank fast and sound like they want to fire then die

Just had both batteries bench tested and both passed with flying colors. 13v each and full CCA Mechanic had a good thought. Make sure the house battery switch is working. Will check that next. If the switch is not turning on the battery it would explain a lot.

He also said then check the plugs as recommended here ….

 

[Dave burke]

That's good news. His idea on the house battery switch is good too.

But if it was my boat, I'd be focused on the starting issue first, ie leave the house battery off and try to start the engines and troubleshoot as we've suggested.

I can confirm the engines should start even with the house switch off. I've done this on my boat lots.

 

[Bruce]

Lead acid batteries that have been below 11V are likely to be damaged.

If the lanyard is not in place the engines will turn over without starting. Might be worth verifying that the laynard is in place and if it is testing that switch.

 

[Shape2001]

The house battery switch checked out and passed the test. Next I will pull the plugs and see how they look

 

[Shape2001]

UPDATE- fixed? I swapped all 3 fuses in the battery compartment with new despite they looked ok. Both battles on - not parallel and hit button to almost fire up. Meaning it sounds like it starts but died immediately. Press again and it ran a second longer pressed again ran a second or 2 longer again. Finally after 6-10 tries it limped back to life. Ran very rough for 30 sec or so before settling in to normal smooth rpm. Same process for starboard side. Required multiple attempts with varying results before finally and barely coming to life. Also settled in after a min or so of running rough. Let both run for 10-15 mins. No warning no errors no beeps. Killed both. Key off. Wait 1 min. Battery both off. Wait one min. Battery both on. Key on. Screen boot up ok. Auto blower on. Press port start button. Instant fire up. Press starboard button. Instant fire up. Will try and take out for a run later tonight as final test but seems all back to normal.

I still cannot access or boot connext with house batter on only but not sure if that’s really a problem or not.

I would say if facing a dead battery issue to bench test first. Double check fuses and if using a push button start do not be shy about hitting it 10-12 times if necessary. Once motor is forced to life the computer seems to take over and get everything back to normal. Fingers crossed and will cold start and test ride later

Thx for all the help and ideas

 

[adrianp89]

I'd venture to say you damaged the batteries.

 

[Neutron]

UPDATE- fixed? I swapped all 3 fuses in the battery compartment with new despite they looked ok. Both battles on - not parallel and hit button to almost fire up. Meaning it sounds like it starts but died immediately. Press again and it ran a second longer pressed again ran a second or 2 longer again. Finally after 6-10 tries it limped back to life. Ran very rough for 30 sec or so before settling in to normal smooth rpm. Same process for starboard side. Required multiple attempts with varying results before finally and barely coming to life. Also settled in after a min or so of running rough. Let both run for 10-15 mins. No warning no errors no beeps. Killed both. Key off. Wait 1 min. Battery both off. Wait one min. Battery both on. Key on. Screen boot up ok. Auto blower on. Press port start button. Instant fire up. Press starboard button. Instant fire up. Will try and take out for a run later tonight as final test but seems all back to normal.

I still cannot access or boot connext with house batter on only but not sure if that’s really a problem or not.

I would say if facing a dead battery issue to bench test first. Double check fuses and if using a push button start do not be shy about hitting it 10-12 times if necessary. Once motor is forced to life the computer seems to take over and get everything back to normal. Fingers crossed and will cold start and test ride later

Thx for all the help and ideas

It was most likely loaded up with fuel and took a bit to clear out. If it stumbles again just replace the plugs