Second battery.

[davel501]

any battery recommendations?

There are tons of threads on the subject. Some like 6v golf cart batteries, some like basic deep cycle marine and others went with AGM. I went with AGM and it seems like sort of a waste of money. Looks cool when you pull the seat off and see the 2 blue tops under there but only 1 in 50 people that you have on your boat appreciates that. Couple of group 24 marine batteries with a good warranty would be the way I would go. Look to get 3-4 seasons out of whatever battery you choose.

 

[Island Jay]

6v in series are great for a long amp hour life. But not all chargers can handle that.

For the rec boater that goes out a dozen times a year, AGM is overkill. But it is a far superior battery, especially if you need to deal with performance
Check out http://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

 

[Tom Duignan]

Can anyone assist me with a problem I just experienced? I recently installed a two battery system on my daughter's Yamaha SX210 jet boat and we used the boat several times with no problems. The other day when she started the engines on battery one, both engines started then stopped. The same thing happened when she switched to battery two. Only when she switched to the "Both" position would the engines remain running and she used it all day with the switch in the "both" position.
has anyone ever heard of this?

Thank You,
Tom

 

[tdonoughue]

What two battery system did you install? Just a switch or a switch and an ACR? Or something else? A photo might help, too...

Also, is the boat on a charger when not used?

Sounds like you have run down both batteries and need to join them in order to start it (which means only a short time before you can't start it at all). Depending on how you wire it, you may not be charging one or both the batteries from the engines (which is only a trickle anyway). That means it will start fine until the battery is out of juice and then you go to the other battery until it is out of juice...

 

[Tom Duignan]

What two battery system did you install? Just a switch or a switch and an ACR? Or something else? A photo might help, too...

Also, is the boat on a charger when not used?

Sounds like you have run down both batteries and need to join them in order to start it (which means only a short time before you can't start it at all). Depending on how you wire it, you may not be charging one or both the batteries from the engines (which is only a trickle anyway). That means it will start fine until the battery is out of juice and then you go to the other battery until it is out of juice...

Thank You for the response; I installed only a battery switch, (1 and 2 and both). Like I said it worked fine for a couple of days but maybe you're correct and they are not charging and only worked because the batteries were new. No, I don't leave it on charge when not in use. I don't know what an ACR is. The mystery for me is, why do the batteries each start the engines when using 1 or 2 but the engines immediately quit and only continue running when the switch is on "both"? Aren't the engines running on own electric when running? ThankYou

Tom

 

[addisonm06]

ACR is an Automatic Charging Relay; it is a separate device from the Switch. There are a few ways these can be wired. But generally the 1/2 are isolated circuits (1 would be for starting battery, 2 for the house items) and Both would combine the 2 batteries.

Do you have a photo of the wiring or installation?

 

[Tom Duignan]

No, I,m not near the boat today so I can't get a photo but I'm pretty sure I remember the setup. I believe I wired the positive cable from battery one to the post on the switch designated for battery one and the positive cable from battery two to the post designated for battery two. Then I wired the positive cable from the two engines to the post designated for that on the switch. As for the negatives, I placed a jumper connecting negative posts on each battery. Then I connected the negative cable from the engines to one of the batteries negative posts. I see a diagram where they recommend that you shouldn't connect the negative cables that way. Could that be the problem?

 

[addisonm06]

Have you checked voltage on the batteries? The negative wiring shouldnt be an issue. It sounds like the wiring is correct.

 

[tdonoughue]

Where did you put the other wire, though. There is a big cable that goes to the engines . Normally though there is a little wire to the positive side as well . Did you wire that to the same terminal on the switch?

 

[Tom Duignan]

Yes, checked the voltage yesterday 11.9 volts on each battery. Then I charged them but didn't check the voltage while the engines were running. I will do that this weekend. Should I get an ACR?

 

[Tom Duignan]

Where did you put the other wire, though. There is a big cable that goes to the engines . Normally though there is a little wire to the positive side as well . Did you wire that to the same terminal on the switch?

Yes all positive wires from engine went to positive post on the switch

 

[tdonoughue]

You don't need an ACR, but they are nice. Without it you should start on battery 1 and then switch to 1+2 while running, and to 2 while floating. An ACR does that for you automatically, basically.

I suspect you don't have that other wire hooked up correctly. That is the wire that provides the charge from the magneto to the batteries to keep it running and charge the battery a little.

 

[Tom Duignan]

Where did you put the other wire, though. There is a big cable that goes to the engines . Normally though there is a little wire to the positive side as well . Did you wire that to the same terminal on the switch?

Yes all positive wires from the engines went to the post on the switch together

 

[tdonoughue]

Ok, moved to my computer, where I can be more useful. Here is a useful diagram: https://goo.gl/images/7kFEpj

Our boats do not have an alternator, technically, they have a magneto. So that is the little wire to which I refer (actually, now that I think about it there may be 2). I would make sure that got connected where you think that it did. I suspect it slipped off or is on the wrong post or something. It should be as you described it, though--on that same post with the starter cables. If it is not, then the charge coming from the magneto (used to fire the plugs) will not get back to the starter wire to get to the plugs. The boat should then run on battery charge until that gets too low to fire the plugs--then it will quit.

Now, at 11 volts I don't think you are that low. But I could be wrong...

Anyway, that is my working theory so far until we have pics or you verify that the little wires are in the right place.

 

[Tom Duignan]

You don't need an ACR, but they are nice. Without it you should start on battery 1 and then switch to 1+2 while running, and to 2 while floating. An ACR does that for you automatically, basically.

I suspect you don't have that other wire hooked up correctly. That is the wire that provides the charge from the magneto to the batteries to keep it running and charge the battery a little.

Where should that other wire be connected then?

 

[Tom Duignan]

Ok, moved to my computer, where I can be more useful. Here is a useful diagram: https://goo.gl/images/7kFEpj

Our boats do not have an alternator, technically, they have a magneto. So that is the little wire to which I refer (actually, now that I think about it there may be 2). I would make sure that got connected where you think that it did. I suspect it slipped off or is on the wrong post or something. It should be as you described it, though--on that same post with the starter cables. If it is not, then the charge coming from the magneto (used to fire the plugs) will not get back to the starter wire to get to the plugs. The boat should then run on battery charge until that gets too low to fire the plugs--then it will quit.

Now, at 11 volts I don't think you are that low. But I could be wrong...

Anyway, that is my working theory so far until we have pics or you verify that the little wires are in the right place.

OK, Thank you very much! You gave me hope and something to check tomorrow. Thanks to all of you!!!!!

 

[Tom Duignan]

Yes that was it! Apparently before the last owner sold the boat he installed a new small battery, (I can't believe Yamaha made this boat with one battery), anyway when he installed the battery he had bundled the positive wires with a tie wrap and bundled the negatives with a tie wrap. When I installed the two new group 31 batteries I just followed suit with the way the wires were bundled. Yesterday I removed one wire from the negative group and connected it to the positive bundle. The engines no longer shut down. I put a meter on each battery separately. With the engine running on battery 1, it shows 13.2 volts and the same when running on battery 2. So I think that is normal. Thank You all for your assistance and patience!

Sincerely,
Tom

 

[tdonoughue]

Glad you figured it out! Good result!

When I had that type of setup (before I got the ACR), I would run on 1+2 (to charge both), start on 1 and use 2 when I was floating (to do stereo, etc.). Sounds like you are all set to do that now. Someday, you will get your Add-A-Battery kit with an ACR that will do all of that automatically. Then you will mod up the rest of the boat...

 

[subysti]

Just remember anything below 12VDC is a dead battery. Hopefully the 2nd battery is a deep cycle battery as you will kill a starting battery You also need to connect to a charger when not in use.

 

[Tom Duignan]

Now I have another question for all you ladies and gents who know much more than I do about a 2010 Yamaha SX210 jet boat;
I see two thin wires coming from a harness at the front of the port engine. I believe these wires were connected to some sort of sensing unit just beneath the exhaust manifold. There are two identical wires on the starboard engine and I followed them down to the same area on the starboard engine. Apparently they were pulled out of some sort of rubber coated sensing unit. Same location on both engine;just below manifold and just above the nose of the starter. I cannot find a clear diagram that identifies this unit and I want to either re-connect these wires or replace the unit. Any ideas what this thing is? The check engine light is on and I'm thinking that this is the reason. Thank You. I.m going to try and send photo.