No 12v Power on the boat!

[billwilletts]

Just bought a 1981 56MY and its very strange but the complete 12v system is down. Even with the 12v charger on there is nothing. The 12V panel power light is not on. I have spent several hours trying to find something major that i am missing but nothing jumps out. Do these boats have a 32v to 12v transformer or do they rely upon the 12v batteries in the generator room? it has to be something major that i am overlooking. Even my surveyor was scratching his head.

I actually have the original manuals and there is nothing in the manual regarding a 12v system. The 12v panel is from the factory though and is in the main electric cabinet with all the rest of the electrical switches at the pilothouse. Any help would be appreciated.

 

[Boatsb]

Most 32 v boats have a 32 to 12v DC converter.

Also many have a second 12v system that's for electronics and has its own battery. The schematics should show either or both.

 

[SEVEN]

First question because I did. Did you turn off anything? Any switches? Push in any buttons? Is the 32 volt system working?

 

[billwilletts]

THe 32v system is working perfect. Whole system checked out. The schematics in the owners manual show nothing of a 12v system but the factory panel is there. I don't know where a converter would be. Checked under the helm and didn't see anything obvious. Not sure the 12v battery condition in the gen room but regardless the charger is on for 12v batteries and charging. Does anyone know if they would have used a 32v to 12v converter in 81 or just relied upon the gen batteries?

 

[SEVEN]

In my 1979 I have just one 12 volt battery which starts the generator. It has its own charger which is in the gen room. I have a 24 volt system that is for the bow thrusters. Those batteries and all the 32 volts are being charged thru the charger inverter system. Another question do your helm gages and radios work?

 

[billwilletts]

All gauges work as does the Robertson auto pilot. That is pretty much it (as far as electronics).

 

[SEVEN]

Are you on the west coast? If so I'll PM you with my number and we can discuss rather than typing everything. Let me know if your interested I send you the cell number. If not tonight another time as well.

 

[Scarlett]

My experience with these boats has shown me that the 12 volt systems on them are all different. As others have said some use 32 to 12 converters, but their locations are all over the place, no set location. Also some, as mine use a combination of converters and 12 volt batteries. It gets even more complicated as people start adding additional 12 volt stuff like toilets , blowers etc. if I were you I would go on a big converter hunt, could be in engine rooms, gen room, under flybridge or under lower helm. Also try to trace any wires hooked to your 12 volt batteries that don't go to the charger or gen's and see if they go up to the panel. Good luck, hope you are a good detective. John

 

[scottinsydney]

In Port engine room may be a shoe box sized black Newmar 32-12 converter. The output wire positive may be traced to a big original fuse on the forward Portside engine room wall. Check converter is turned on and that fuse has not blown. I replaced this fuse with a circuit breaker as I had similar issue.

 

[johnjen50]

My Newmar 32/12 converter is in the strbd engine room. There is a switch on top of the unit and a green light indicates it is on. No green light no 12 volt anything.

 

[billwilletts]

These are the only boxes I can find that resemble a converter. It looks like these power possibly individual electronics at lower helm? These 3 boxes are underneath the lower helm - nothing on the upper.

Ok well it won't let me upload or share a link. I get an error when i upload the file - its only 1MB. When i try to share a link it says invalid link LOL. This is harder than working on a boat.

 

[MikeP]

There was no 12v on the boat from Hatt OTHER than the 12 v converters at the helm to operate the gauges. If there is a 12V system on board, it was added at some point. Therefore, there is no telling how well or badly it was "designed" by whoever did it.

The OEM wiring diagrams that came with the boat show what was there when it left the factory. Anything not shown there was added by somebody. It may have been done well, in accordance with the recommended practices at the time but there's a good chance that it was installed by whatever method seemed the easiest to whoever (PO or Mechanic) did it.

Quite often, when the OEM Generator was replaced, it was replaced by one that used a 12vdc starter as opposed to the OEM Genny with a 32VDC starter. Sometimes that 12v "system" (which would have been just a 12 battery for the Genny starter) was expanded. Again, whether it was expanded in accordance with correct practice or just jake-legged will totally depend on the PO...

 

[SEVEN]

That's exactly how. One is set up Mike. I've been texting him and the. If issue is his batteries are all dead. Although you are correct and some prior owner switched things to 12 volt on some items. I'm going to call him and discuss it.

 

[billwilletts]

Thanks guys - I have photos of what is there and also of the 12v panel which looks OEM but it must not be if what you say is true. It looks exactly like the 32v panels and is right in the same electric panel as the OEM ones so they must have left room for one to be added. At any rate I am not on the boat any more but I am going to start at the panel and trace the power backwards to see where the source is. Any suggestions on a 12v tracer?

I have not used this forum before to post - but I have been a long time reader. Why won't it let me upload photos or link to one? I see others doing it.

 

[SEVEN]

Adding photos is easy once you know how to do it. The hard part is explaining how to do it. Maybe when we talk I'll walk you through it.