Starting and breaker panel

[Terry Kerr]

Inside my salon I have a panel of circuit breakers. Among them are two that say “Port Engine” and “Starboard Engine”.

Ever since I bought the boat, if I wanted to start the Port engine, that port breaker would have to be on. Then I would need to go up top and the port start on/off rocker switch would have to be switched on (there is no key). Then immediately an alarm would sound. After that, I would push the start button and the engine would start and the buzzer sound would disappear as the oil pressure rose. To turn the engine off simply turn off the start on/off rocker switch. This all sounds reasonable to me.

However, the starboard side is very different. It doesn’t matter if the breaker is on or not. If I am up top and the start rocker switch is on, buzzer sounds and then pushing the start button the engine starts and the buzzer turns off as the oil pressure rises. This is regardless of the circuit breaker in the salon. In addition if the start rocker switch is off and I push the start button, the engine starts and then dies.

I’m guessing it starts and then dies because the fuel solenoid gets turned on with the start rocker switch?

While both engines start fine I don’t like that the breaker below may have somehow been bypassed or the breaker is fried and is on all the time. to test the latter, I removed the breaker completely, disconnected ALL the wires attached to it, so nothing was connected and the engine still starts. Hmmmmmm

Before I charge ahead, I need to get a better understanding of how the wiring works (I have no idea how to read a wiring diagram nor do I have one).

Both port and starboard circuit breakers are wired identical. There is a single red wire going to the “hot” side of the breaker that shows voltage on my meter in the on of off position . On the other terminal there are 3 red wires. One tiny one that goes to the indicator light. One medium sized one and one thicker one.

Assuming that the port is functioning as designed, then can somebody explain how it all works? what do the medium and thick red wires on the “non hot side” actually do?

I would think they would work their way up to the start on/off swtich/start button and then back down to the starter and fuel solenoid?

TK

Topic

[Terry Kerr]

Each diesel can run independently

Yes each can start and run independently. There are separate thick red positive wires going to the flybridge and straight to my port and starboard on/off switch. The bridge breaker can be off and both can run. The Cabin breakers can be off and both can run.

However if everything is off, including the port engine breaker, the the port engine will not start, as expected. flip that breaker and the port starts right up.

But if everything is off, including the starboard engine breaker, the starboard engine will start right up.

I tested the breaker, it is fine. I don’t think the wiring is hooked up through that breaker.

My guess is when the previous owner ripped out the gas engines and installed the diesels, they bypassed that breaker for some reason.

My question was: does it only take two positive wires to start a 6BTA? one heading to the starter and one heading to the fuel solenoid?

If so, then I need to find them and trace them back to the helm and see if I can redirect them back to the breaker.

Also looks like a guy in England on the Luhrs forum has a wiring diagram. Guess i need to learn how to read these things…..

[Tony Athens]

No way, no how could this be sorted out without a complete wiring diagram of what you are trying to explain.. And even then, only a maybe.. Sounds like this is a boat builder thing & not a Cummins thing..

If the engines are somehow tied into the the house wiring system, then IMO, that is major mistake #1.. SORRY, but the engines should be able to run independent of each other, and anything to do with the rest of the boat.. That’s the #1 idea behind have twins and “diesels” .

[Author]

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