Engines won't start!!! Batteries?

[buster53]

My suggestion on batteries...others may not agree,
Genset should have a starting battery as that is all it does..start the genset.
The other 2 are both house and starting batteries. They both should be deep cycle. They will start your engines just fine and will better hold up to the needs of the house.
I had a Carver 3807 for 7 years with twin 7.4's and my deep cells never caused us any problems.
Some may suggest the dual purpose deep cell/ starting battery. I've read lots of threads over the years saying that is not a good way to go.

[tomschauer]

Rickie, when on shore power your battery charger should charge the batteries no matter what the position of the switch is. If you have it off, none of your 12 volt accessories will work, such as your lights. I would leave it on 1 or 2 and switch it every other week or something like that.
Your nav lights are of course 12 volts, so if your 12v is dead no nav lights. If your other 12v stuff works on the bridge, dash lights depth finder etc. It is an isolated issue. I would check each light individually. Id doesn't take much for these to stop working. Pull a bulb, test it for continuity, and test for 12v with the nav light switch on. If both are ok, take some light sandpaper and clean the fixture contacts and the bulb contacts.
If you don't have 12v check the Nav light breaker. Mine is on the bridge under the front seat, not sure where they are on a Mariner.

[jcoll]

Source of the post My suggestion on batteries...others may not agree,
Genset should have a starting battery as that is all it does..start the genset.
The other 2 are both house and starting batteries. They both should be deep cycle. They will start your engines just fine and will better hold up to the needs of the house.
I had a Carver 3807 for 7 years with twin 7.4's and my deep cells never caused us any problems.
Some may suggest the dual purpose deep cell/ starting battery. I've read lots of threads over the years saying that is not a good way to go.

My experience with batteries has been the same. The deep cycles start the engines without any noticeable down side. Longevity has been good and the deep cycle is what I want when anchoring overnight.

[mjk1040]

When we are on shore power, our charger is always on smart charging our batteries. When we leave the boat we turn the batteries to off. We leave the battery charger on and the receptacle breaker that the fridge is on, that's it on the AC panel. We also turn off shore water. Also, every chance we get we exercise our generator, at least once a week and/or if go out the generator is running. If u don't use it, u will loose it. Also, during the winter months we will plug the shore power in while we are at the boat to charge up the batteries and run a ceramic heater to warm the boat as we work. Each boater has there own preference on this issue.

[RickieT]

Well I charged the batteries using the Noco Genius G3500 and both are at 100%. Tried to start both engines and both still won't turn over. I tried placing knob on "both", engine 1, and engine 2 none would turn over.
Any thoughts?
Got a guy helping me and my next step is to bring the 2 batteries in to be load tested. They can read 100% charged and have no current according to him. So frustrating...want to her out to see if port engine is still overheating and can't even start the damn boat to do so!

[bud37]

Have you tried giggling the shifters around as you have the key turned to start?.....any clicking sounds at all....all the engine grounds from the batteries clean and tight?......You had the boat running before all this, correct ?

When you turn the key to start do you hear the start alarm, at the engines do you hear anything at all ?

[tomschauer]

Rickie, +1 on what Bud says above, also look at your volt meter on the dash (assuming you have them) when you turn the key to start does the meter nose dive? If not, its something else not even letting you try to start.

[RickieT]

Thanks....I do hear the start alarms then turn the key and hear clicking noises. I will go back to the boat and try giggling the shifters and also make sure the engine grounds are clean and tight. Will also check the volt meter on bridge...Thank you all!

[Viper]

If you hear clicking the shifters are in neutral. Do you hear a single click or does it keep clicking for as long as you have the key in the start position? A few possibilities but the type of clicking is a clue.

[RickieT]

When I turn the key it clicks continuously and after a bunch of tries no more clicks. The first couple of tries the engine want to turn over but after that just the clicks.

I checked the handles are in neutral and when try to start either engine the volt meter dives right down.