A Really Strange Wiring Problem that I need Advise on....

[patrol50]

Hi Fed it is a 2006 Mercury Optimax 2 Stroke so not that old. Looking at the Manual it would suggest only two wires from the engine (pos and neg) and the wiring for the instrumentation cluster.

I live in Carindale on the Southside

obvious question is do you have 2 batts or do you have a 2 nd thick neg wire to a sounder etc if not then not quite sure what that 2nd heavy neg cable is in there for - if you want an expert opinion on it give grand marlin a quick look at it or trimax marine - both are good but not inexpensive although money well spent usually

cheers rob

PS carindale is on south side of brisbane and not too far from trimax marine - grand marlin is a mobile elect tech and located north side of bris

[Fed]

Yes only 2 wires for your motor.

The way I see it you have a good circuit diagram, the boat right in front of you and you still have a problem. Maybe someone here could show you or you might have to take it to a sparky.

I'm guessing Carindale on the Southside is no where near Sydney?

I'm pretty sure I've discussed the pros & cons of electrically isolating your motor from the hull with juggernaut before and we've agreed to disagree.

I say they should be connected for the following reasons.

Mercury say it offers your hull anode protection via the motor anodes.
It's pretty much impossible to 100% electrically isolate them anyway.
If you did manage to isolate them a short circuit any ground to your hull would start dissolving your transom like an Aspro.
As above if your hull is grounded to a battery negative.

Having said that I believe Quintrex do or did ground there hulls to a battery negative at some point... go figure?

Popcorn anyone?

[blairv70]

obvious question is do you have 2 batts or do you have a 2 nd thick neg wire to a sounder etc if not then not quite sure what that 2nd heavy neg cable is in there for - if you want an expert opinion on it give grand marlin a quick look at it or trimax marine - both are good but not inexpensive although money well spent usually

cheers rob

Rob

I have two batteries with the negative termainals joined together with a thick guage cable - check out the diagram I posted up. The mystery remains what are the other two for?

The wires are hard to access as they run back into a deep transom - I am guessing I might disconnect them and then test out everything and see what does not work - process of elimination I guess.

Blair

[patrol50]

Rob

I have two batteries with the negative termainals joined together with a thick guage cable - check out the diagram I posted up. The mystery remains what are the other two for?

The wires are hard to access as they run back into a deep transom - I am guessing I might disconnect them and then test out everything and see what does not work - process of elimination I guess.

Blair

sorry blair should have logged in so i could see the diagrams before replying previously -

dont know the answer to your neg setup mate so maybe process of elimination good way to go

cheers rob

[blairv70]

Well success at last! Found out some weird things though - there were 2 x negative leads between the batteries - not sure why......

Also the old fuse holder of the house wire had 12.7 v coming in and 6-9v coming out so replaced that, removed the additional lead and all is working well

I have relocated all gournd leads from the hull to the negative terminal.

Thanks everyone for your help

Blair

[tjotter]

Attachment 97725
Here is a full diagram of my wiring setup

So how did you "create" that wiring diagram ?
I like the combination of coloured Wires to show how stuff is connected & the mini-photos of the bits of Equipment.

[blairv70]

So how did you "create" that wiring diagram ?
I like the combination of coloured Wires to show how stuff is connected & the mini-photos of the bits of Equipment.

I used a program called Visio that I normally use for network diagrams for my line of work. Pictures were copied and pasted from the net (google is your friend here)

[thelump]

Work in the data/fibre optics industry blairv?