intermittent complete power loss

[deepdesire]

The 40A red breaker and House12V should have no effect on the motor or its gauges. You can disconnect the House from the battery entirely and still operate the motor.
The motor gets its power thru the starter cable and sends 12v out to the controls and gauges thru its motor harness.
The motor however can effect the House 12v if they are using the same battery. Starting a motor draws a lot of current and that can temporarily drop the battery voltage (which is the House voltage)

Skunk your AP's are fly by wire? Check your ignition switches and see if they grabbed a power source at your helm. My Engine gauges are veiwed through the MFD and Suzuki/Simrad Is35 gauge via the nmea2k network which is powered through the ignition switch. The ignition switch grabs its hot source off the lower helm fuse block. Interupt that source and you loose gauges and engine. Whenever the key switch is on the n2k network is up. Engine controlled thru start stop switch. No load on start battery unless starting

 

[SkunkBoat]

Skunk your AP's are fly by wire? Check your ignition switches and see if they grabbed a power source at your helm. My Engine gauges are veiwed through the MFD and Suzuki/Simrad Is35 gauge via the nmea2k network which is powered through the ignition switch. The ignition switch grabs its hot source off the lower helm fuse block. Interupt that source and you loose gauges and engine. Whenever the key switch is on the n2k network is up. Engine controlled thru start stop switch. No load on start battery unless starting

hmmmm... you might be right! I was thinking my old Yamahas. The Suzuki gauges have a separate N2k Power from the rest of the network. I can't remember if it goes to the house panel or if it is fed from the motor harness. I have SMG4 gauges.

That would be a weak point in the system. It SHOULD be fed directly (thru a fuse) from the Start battery (port?).

Looking at the manual I think I was right. I have to check the boat but I do remember a small Black & White battery connection from the Zuke harness
Check yours. There should be a Black and a Gray bullet connector in the helm harness to feed the Zuke N2k power bus. To connect the Zuke N2k bus to the rest of the N2k network you need a power isolator N2k connector. It connects the data lines but not the power. The other half of the N2k needs it own power feed from the House 12V.
I really don't think your Key switch should be getting power from the house fuse panel.. maybe someone took a shortcut?

Sorry for thread creep but it is related to the OP question.

 

[Fishtales]

The boat is almost new. I'm betting a connection issue or maybe incorrect installation of battery cables that were likely removed for layup.

 

[pineislander]

Thanks all for the responses.

Called the dealer yesterday and since they happened to be in the area stopped by to check out the boat. They believe the issue is a loose post on the battery selector. Connections tight, but when moving the wire the post moved. They will replace later this week.

 

[Fishtales]

Good find... Glad to see that it is isolated and hopefully resolved. Will be a boost to your confidence on the water.

 

[HMBJack]

That discovery perfectly explains your issue.

An intermittent power loss is a huge safety concern.
Take off that defective battery selector and hit it hard with a sledge hammer!

 

[deepdesire]

hmmmm... you might be right! I was thinking my old Yamahas. The Suzuki gauges have a separate N2k Power from the rest of the network. I can't remember if it goes to the house panel or if it is fed from the motor harness. I have SMG4 gauges.

That would be a weak point in the system. It SHOULD be fed directly (thru a fuse) from the Start battery (port?).

Looking at the manual I think I was right. I have to check the boat but I do remember a small Black & White battery connection from the Zuke harness
Check yours. There should be a Black and a Gray bullet connector in the helm harness to feed the Zuke N2k power bus. To connect the Zuke N2k bus to the rest of the N2k network you need a power isolator N2k connector. It connects the data lines but not the power. The other half of the N2k needs it own power feed from the House 12V.
I really don't think your Key switch should be getting power from the house fuse panel.. maybe someone took a shortcut?

Sorry for thread creep but it is related to the OP question.
View attachment 25517

Skunk did you ever verify your wiring? I split my network and ran a dedicated clean power source from the start battery. Suzuki C10 gauge and engine interface only are active when key switch is on.

 

[SkunkBoat]

Skunk did you ever verify your wiring? I split my network and ran a dedicated clean power source from the start battery. Suzuki C10 gauge and engine interface only are active when key switch is on.

Mine is correct. In the Suzuki Port wire harness there is a White+ and Black- wire that goes to the Port Start battery. (Port is the default harness for single motor, Stbd is added)
That feeds the Key switch and controls. The Key powers the Suzuki N2k bus which powers the SMG4 gauges. The Suzuki 2k bus power is isolated from the rest of the 2k power.(google N2k power isolator) Only the data wires connect. This is by Suzuki design. Motors and gauges should run independant of your electronics wiring. Their design even calls for an N2k GPS antenna/receiver to give you speed and fuel economy data. They put that in the rigging price and take it out if you have GPS and don't want another antenna. They assume your boat has nothing.

You should look for the W &B wires. They should be on your battery.

Your electronics network should have an N2k power cable on the other side of the N2k isolator. Usually fed from the fuse block.

 

[deepdesire]

Mine is correct. In the Suzuki Port wire harness there is a White+ and Black- wire that goes to the Port Start battery. (Port is the default harness for single motor, Stbd is added)
That feeds the Key switch and controls. The Key powers the Suzuki N2k bus which powers the SMG4 gauges. The Suzuki 2k bus power is isolated from the rest of the 2k power.(google N2k power isolator) Only the data wires connect. This is by Suzuki design. Motors and gauges should run independant of your electronics wiring. Their design even calls for an N2k GPS antenna/receiver to give you speed and fuel economy data. They put that in the rigging price and take it out if you have GPS and don't want another antenna. They assume your boat has nothing.

You should look for the W &B wires. They should be on your battery.

Your electronics network should have an N2k power cable on the other side of the N2k isolator. Usually fed from the fuse block.

Thanks for the insight. I have made the corrections to my network and pulled wiring from battery to new connection on Suzuki harness W and B wires. What size fuse was used on that white wire for circuit protection? Thanks in advance.

 

[SkunkBoat]

Thanks for the insight. I have made the corrections to my network and pulled wiring from battery to new connection on Suzuki harness W and B wires. What size fuse was used on that white wire for circuit protection? Thanks in advance.

mine is 30A.. Check you wiring diagram on last couple pages of your manual. Its tiny and hard to read so scan it to a pdf and then you can zoom

 

[deepdesire]

mine is 30A.. Check you wiring diagram on last couple pages of your manual. Its tiny and hard to read so scan it to a pdf and then you can zoom

View attachment 25627

Thank you sir!

 

[ItalianAngler]

I had this exact issue occur on my other boat, it turned out to be a post connection that vibrated loose in the rough seas. Tightened up and not an issue since, drove me nuts searching for a week solid.

 

[deepdesire]

mine is 30A.. Check you wiring diagram on last couple pages of your manual. Its tiny and hard to read so scan it to a pdf and then you can zoom

View attachment 25627

Hey Skunk, cant get this out of my mind, those hot and ground power wires are no more than 18ga. Why would Suzuki install a 30 amp fuse on such a low amp carrying conductor? Any thoughts?

 

[seasick]

Hey Skunk, cant get this out of my mind, those hot and ground power wires are no more than 18ga. Why would Suzuki install a 30 amp fuse on such a low amp carrying conductor? Any thoughts?

The only reason for that would be to fry the wires to protect the fuse
Maybe that should have been a 3 amp....

 

[SkunkBoat]

Hey Skunk, cant get this out of my mind, those hot and ground power wires are no more than 18ga. Why would Suzuki install a 30 amp fuse on such a low amp carrying conductor? Any thoughts?

idk. I never looked at it until I took that screenshot. That was connected by installer. I have never looked at the fuse inside the inline fuseholder. I don't know that its 18awg at the battery.

 

[deepdesire]

idk. I never looked at it until I took that screenshot. That was connected by installer. I have never looked at the fuse inside the inline fuseholder. I don't know that its 18awg at the battery.

It is fine small wire. I opened the fuse holder and its a 30amp for sure.

 

[seasick]

If so, I would change it for something a lot smaller, probably 5 or so.

 

[deepdesire]

If so, I would change it for something a lot smaller, probably 5 or so.

Suzuki wiring diagram in engine manual shows fuse as 30 amp. See Skunkboat's post and diagram of April 27.

 

[seasick]

If the wire gauge is as small as you say it is, a 30 amp fuse is a recipe for a fire should the circuit short out. Something is not right.
Skunkboat's diagram does not show wire gauge. If the fuse is correct, the wire size is wrong. If the wire size is adequate for the expected load, the fuse is sized too big.

 

[SkunkBoat]

Its factory. They did it for a reason. leave it alone.