Battery Issue

[Jonah]

Hi all,

My neighbor is having trouble with his 'otherboat'. His single Yamaha 150 will not start unless he selects 'both' on the selector switch. But this is true even with two new batteries (group 24 starters). I'm guessing it's an amperage issue, caused by some bad connections somewhere. Any other ideas of where to start the troubleshooting?

 

[seasick]

First of all, it helps to know what 'won't start' means. Does the motor crank normally but not fire or does it not turn over at all or slow? I would suspect the later.
Assuming your neighbor is not electrically savvy and wants to try to fix the problem, the place to start is checking and cleaning all the contact and connection points. Also have him or her make sure that the common cable that connects the two batteries together is indeed connected.
Don't forget that there are connections at the motor that could be bad but if so, I don't think selecting BOTH would help for the positive feed. It is possible that the switch itself is bad but the likelyhood of that is a lot less than just a corroded connection.My bet is an issues with a ground cable. The ground cable does not go through the switch so check the battery grounds AND the connection at the motor. When checking the motor connections, make sure the switch is in the off position.
A wire brush and/or a piece of emery paper will be helpful for the cleaning.

 

[Jonah]

Thanks Seasick,

Yes, sorry for failing to mention: he can use the power-trim, and the outboard will turn over, just a bit, but not start. (I haven't heard this myself, so will try to be around the next time he tests it.)

I'll help him check for corrosion, loose connections, etc. Thanks for the tips.

 

[Fishtales]

Sounds like he's swapped the batteries out and either disturbed something (connection) or didn't connect properly.

 

[Halfhitch]

While you have the batteries disconnected looking for poor connections and don't find an obvious problem, it would be a good time to check the voltage in each battery and write it down, keeping track of which is which if they are removed from the boat. Charge each battery separately with a modern charger. If they charge to 100% with no issues indicated by the charger then remove the charger and measure the surface charge within 5 minutes of removing the charger and write it down. Let the batteries rest for 12 hrs. without connecting them to anything. Check the voltage and write it down. The surface charge immediately after disconnecting the charger should be 13 to 14 volt range. It should dissipate after a few hours to 12.8 volts ideally. Write this reading down with the other information and compare all the readings. looking for abnormalities between the two. If you have a load tester you can identify a questionable battery by testing immediately after disconnecting the charger. If you have a hydrometer and understand its' use, it is a very good tool to identify battery state of charge. Also look for any bulging of the sides of the battery cases.

I look at the cost of a battery in a boat as about 1/3 of a tank of fuel. Not worth using if any doubt about it because it could prevent you from getting home...(that's where supper is waiting) If I have 1/3 of a tank of fuel that is of questionable quality, I would throw it away because it could cause me to miss supper also. Same deal with a battery. If it were my friend I was helping and his batteries weren't up to snuff, I would encourage him not to risk using a questionable battery unless he's just going out on a small lake.

All this is just my 2 cents and meant only to give you something to consider. Let us know what you find.

 

[seasick]

For the record, A fully charged lead acid battery not under load and at 65 degrees or so should read just about 12.6 volts. At 12 volts it is pretty much discharged . In cases like these, measuring the standing battery voltage is not that helpful. Load testing the batteries is a better test since it will show weak cells. Place like Autozone will do that test for free.

Measuring the battery voltage at the battery while cranking the motor will tell you a lot since that is basically load testing. Once you know that figure, measure the voltage at the motor main solenoid terminals. With no load, it will be the same as the standing (no load) battery voltage.
Cranking the starter however will give you a lower reading due to voltage drop. If the battery is in decent shape, you will see a drop at the motor than at the battery terminals. If the voltage drops to a few volts at the motor but not the battery, you have a bad cable or connection somewhere (positive or ground circuit)

First thing as mentioned is to make sure all the ground cables if removed are reconnected at the batteries. At a minimum for single engines, one batteries negative terminal will have one fat cable and the other battery negative terminal will have two fat cables.

 

[suzukidave]

i crossed up the two ground cables on a dual battery set up with only one battery installed and had this issue. it worked on "2" but had no power to crank the motor and the tilt was slow. took a little while to figure out.

 

[seasick]

i crossed up the two ground cables on a dual battery set up with only one battery installed and had this issue. it worked on "2" but had no power to crank the motor and the tilt was slow. took a little while to figure out.

I've done it myself

 

[Jonah]

I've done it myself

Seasick and SuzukiDave, could you explain this a bit further? Isn't it just that one battery's negative needs to go to the other's negative, and that negative needs to go to a ground? How is it possible to mess up the ground cables?

Or are you referring to the negative cable coming out of the outboard, and needing to make sure you send that one to the same battery as its positive cable?

 

[suzukidave]

if you cross the battery cables and connect the positive terminal on a battery to the "1" positive cable from the switch and the negative battery terminal to the "2" position negative cable then the battery will only work at all in the "both" position and it will be weak because the ground is flowing through the switch crossover.

 

[seasick]

Seasick and SuzukiDave, could you explain this a bit further? Isn't it just that one battery's negative needs to go to the other's negative, and that negative needs to go to a ground? How is it possible to mess up the ground cables?

Or are you referring to the negative cable coming out of the outboard, and needing to make sure you send that one to the same battery as its positive cable?

If all cables and connections are good for a single motor, two battery configuration is doesn't matter which battery the positive is fed from and which the motor ground is connected to.. What happens often is that folks miss the interconnecting cable connection. If the battery that isn't connected to the main ground cable has a cable for something else like the accessories ground, the current from starting flows through that cable but since the cable gauge is too small for that load, there is excessive voltage drop and the motor won't start. Sometimes the Bendix drive of the starter will even spin too slow for the gear to engage the flywheel.
Whatever the issue, it shouldn't be very hard ti isolate assuming you understand the theory Easy for me to say, I was and I guess still am an electrical engineer.

 

[SkunkBoat]

my head is spinning....

To get to the bottom of this;

start from scratch. Draw a diagram of the connections. compare your diagram to google search of a typical 1 motor, 1 switch, 2 battery system. if they are not the same, yours is probably wrong.

disconnect both batteries from the switch and each other and disconnect the motor from the switch.

connect the motor to one battery. start the motor. good yes /no?
disconnect from that battery and connect the other battery to the motor. start motor. good yes/no?

Both yes? your switch may be bad or wiring is wrong or bad connections or wire> >>> test the switch with a meter if you know how or replace it if its old regardless. Inspect all wires for signs of "green", hard spots that don't flex, frayed wire at connectors. Replace suspect wires. Reconnect the (new?) battery switch per the diagram.

Both not right? probably the cable to the motor or connection at the motor. Inspect motor wires for signs of "green", hard spots that don't flex, frayed wire at connectors.

one good, other bad? you have a bad or weak battery.



I recommend Marinco EZ Mount Selector Battery Switch....wires connect from the FRONT!!!!!

 

[seasick]

I should have just asked up front the following: Did the motor start last season and did the owner remove, disconnect or replace batteries before the problem arose? It really shouldn't be so complicated to fix.

 

[Jonah]

Thanks everyone, this is very helpful, and super interesting.

The neighbor bought the boat from our other neighbor a few months ago. At the time of purchase, the previous owner (other neighbor) said that for some reason the outboard only starts when the selector switch is on "both". When I heard that, I thought it might be a battery issue, and told the new owner to remove both batteries and put in my spare starter in Battery 1 space. He did, and the outboard still wouldn't start. (Turned over a bit, but wouldn't start.) So, he figured it wasn't a battery issue and put back in the old batteries, and returned my spare.

I suppose, now that I think about this cross-wiring possibility, that he could/should have tried selecting "Both" even when he had only my one starter in the Battery 1 space.

Anyway, I'm going to help him look for corrosion or loose connections. If that doesn't solve it, then I'll also trace his cables and make sure nothing is crossed. Skunkboat, your suggestions will be helpful there.

Will report back. Love learning new things on this forum. You guys should set up an online course. I'd pay good money for it. (Wait, don't do that; I like getting your advice for free!)

 

[seasick]

'I suppose, now that I think about this cross-wiring possibility, that he could/should have tried selecting "Both" even when he had only my one starter in the Battery 1 space. '
I don't think the motor would have started..

One thing to make a note of. If there are two batteries and the motor won't start on either but does on BOTH, the problem is more likely either 'dead' batteries or some part of the circuit that is common to the motor regardless of which battery is selected. That sort of eliminates the individual red (positive) cables to each battery from the switch. It also probably eliminates the connections at the motor. So what is left is the switch and common connection (red to the motor) and the common ground (Black) cable from the motor to the battery. To check the switch you will have to remove it. You will see the connections on the back but can't tell if something internal is bad. Those switches are pretty reliable as long as they stay sealed)
As mentioned, those cables can get corroded underneath the connectors and if the ends have heat shrink tubing, you may not be able to easily see the problem. If you suspect a bad lug, you may need to cut off the shrink tubing.

 

[SkunkBoat]

here's a pic of a "green" cable that I accidentally found on my 11 year old Suzuki 140 when I was doing my transom repair. I noticed a spot that did not flex quite like the rest and a very tiny green dot in the black rubber.
Eventually, this would have been a failure to start...probably 60 miles out in Chicken Canyon....

point is... it doesn't have to be the ends of the cable, although they are more likely.

 

[seasick]

here's a pic of a "green" cable that I accidentally found on my 11 year old Suzuki 140 when I was doing my transom repair. I noticed a spot that did not flex quite like the rest and a very tiny green dot in the black rubber.
Eventually, this would have been a failure to start...probably 60 miles out in Chicken Canyon....

point is... it doesn't have to be the ends of the cable, although they are more likely.



View attachment 5850

Nice photo. Was that at a spot where the cable bent, rubbed a grommet or a rigging tube?
To corrode like that in the mid section of a cable, there has to be moisture intrusion like an abraded outer covering.
You point about the cable feeling harder is a good point. Anywhere a cable changes its stiffness can be a problem, The area could be stiffer as yours or more flexible like when a crimped lug loosens up.