Yamaha corroded ground wire.

[KJM]

Yesterday i had to be towed back to the slipway (oh the shame!). The motor just lost all power while idling. I checked wires and some fuses, no luck. Anyway when i got home and proceeded to see what was the problem the ground wire came clear of the battery with the connecter still on the battery! Problem solved, but I noticed that the connector was steel while the wire is copper. Would this cause it to corrode thru because of dissimilar metal? The copper wire had turned green and brittle where it joined the connector.

 

[99yam40]

Yesterday i had to be towed back to the slipway (oh the shame!). The motor just lost all power while idling. I checked wires and some fuses, no luck. Anyway when i got home and proceeded to see what was the problem the ground wire came clear of the battery with the connecter still on the battery! Problem solved, but I noticed that the connector was steel while the wire is copper. Would this cause it to corrode thru because of dissimilar metal? The copper wire had turned green and brittle where it joined the connector.

bad connection heats up that connection and caused it to burn and get brittle.
if you check and clean/lube the battery connections like you should this would not happen

 

[KJM]

bad connection heats up that connection and caused it to burn and get brittle.
if you check and clean/lube the battery connections like you should this would not happen

The motor is new to me this year, I did clean and lube the connection but maybe the previous owner never did this. I missed the corrosion because it was under a black rubber wrap at the join between the end of the wire and the ring terminal connector. Lession learned.

 

[99yam40]

I would not like to have a steel connector on a saltwater motor/boat, but even the lead to copper connections go bad sometimes also.
I have seen cables go bad in the middle of the cable too

 

[KJM]

I would not like to have a steel connector on a saltwater motor/boat, but even the lead to copper connections go bad sometimes also.
I have seen cables go bad in the middle of the cable too

The new one I put on was copper. Haning a cable go bad in the middle somewhere would be hard to track down.

 

[boscoe99]

If the crimp did not hold the wire in place the solder should have.

Very interesting that a cable completely come out of its connector.

 

[KJM]

It didn't come out of the connector. it corroded away exactly at the point where the connector and wire meet. There was still some wire left in the connector.

 

[boscoe99]

What does "came clear of the battery" mean?

"the ground wire came clear of the battery with the connecter still on the battery!"

 

[boscoe99]

The new one I put on was copper. Haning a cable go bad in the middle somewhere would be hard to track down.

A voltage drop test will tell you this.

 

[KJM]

What does "came clear of the battery" mean?

"the ground wire came clear of the battery with the connecter still on the battery

What does "came clear of the battery" mean?

"the ground wire came clear of the battery with the connecter still on the battery!"

 

[KJM]

The ground wire broke off from the battery and left the connector still attached. Am I right to assume this would cause the motor to die while idling? Its a 2016 Yamaha F90 EFI.

 

[dingbat]

Am I right to assume this would cause the motor to die while idling? Its a 2016 Yamaha F90 EFI.

Amongst other things.....
Lucky you didn't take out the charging system in the process.

Steel connectors will suffice for automotive applications but a no-no for marine applications.

Guessing the cable isn't "Tinned" as well. Better off to replace the cable with a Marine grade cable

 

[KJM]

Its the wire that came with the motor, i think its the original equipment, its likely stainless steel as its not rusty. Its also not tinned that i can see. I was thinking about the charging system as well as this would be similar to turning off the battery switch while running wouldn't it? Must have some kind of protective system (diode?) built in. Would it cause the motor to die while idling?

 

[boscoe99]

The wire in Yamaha battery cables is not tinned. Just plain copper. But the cable is usually soldered to the crimped on end fitting as one corrosion protection method.

Most Yams will not run with the battery disconnected. Some might idle but if you come up on power the motor will die.

A battery becoming disconnected from a running motor may or may not harm the electrical generation system. More likely if the motor is running at power than at idle but it does not always happen. Because it might, care is taken to prevent it from happening.