Constant drain of 1 of 2 batteries

[nola mike]

So no connection between the batteries? What's a parallel switch? And stbd is the draining battery? Seems like an odd setup.

 

[dingbat]

One of the batteries for stbd engine and everything else, the other battery seems to be for port engine only. and I have a parallel switch on dash.

A battery switch on the helm is weird.
Never heard of or seen of such a thing on a Grady.

I have a light at the helm that lets me know when the ACR is active.
Have a OFF/ON/Combine switch on the transom

What year and Model?
All the Grady wiring diagrams are on-line

 

[nola mike]

A battery switch on the helm is weird.
Never heard of or seen of such a thing on a Grady.

Can't be a regular battery switch, it would take too much high current wiring

 

[crazy charlie]

So no connection between the batteries? What's a parallel switch? And stbd is the draining battery? Seems like an odd setup.

Got the boat with that setup over 20 years ago and never thought twice about it. Never an issue. Parrelel switch is a spring loaded toggle on the dash which when held to "on"connects both batteries momentarily for startup when 1 battery is weak.

 

[dingbat]

Can't be a regular battery switch, it would take too much high current wiring

Not necessarily.
A 12V switch would be all that is required to actuate a remote battery isolation relay.

If that is the case, that would be high on my list of things to check as well.

 

[nola mike]

Not necessarily.
A 12V switch would be all that is required to actuate a remote battery isolation relay.

If that is the case, that would be high on my list of things to check as well.

Yeah that's why I said "regular", would have to be a relay trigger with the relay near the batteries, which is what it sounds like. A stuck closed relay might do strange things

 

[crazy charlie]

The switch is working fine and does exactly what it is supposed to by giving me both batteries for the moment of cranking to start.

 

[dingbat]

The switch is working fine and does exactly what it is supposed to by giving me both batteries for the moment of cranking to start.

Doesn’t have to be “broken” to be leaking current across the windings