Grounding the Gauges

Hi Kevin.

I recently bought all new gauges for my 1985 Evinrude 140VRO, including a tach, GPS speedo, fuel and water temp.


My problem is that I am struggling with the term GROUND! I have a fiberglass boat, so is Ground the same as Negative?

Can you please advise.

Many thanks


You are correct.

On your boat, Ground is the same as the negative of the battery.

Hope this helps,


Hello Kevin

That does help.

Could you please answer another question?

I'm hooking up a second battery, deep cycle. Can I have a common buzz for negative ground for both battery's? Do all the new gauges need to be fed from the cranking battery? Or does it not matter?

Thanks for your help.

 Best regards!


Yes. Use a common ground when adding a second battery.

No. Not everything needs to be fed from the cranking battery.

Keep in mind that without some method of connecting the positives of the batteries (switch, charger, smart switch, etc), the second battery will not be charged by the engine alternator.


Neutra Salt Installation

Hi Kevin,

I bought a used Volvo Penta Neutra Salt system. It did not come with instructions for the boat wiring. Volvo Neutra Salt system

It seems fairly easy to hookup, but I’m wondering the best way to hook up to a power source. The + wire has an inline fuse, with a round connector on the end – looks like to hook up to the ignition switch? This system only needs to work with the engine running, so that’s why I’m thinking it goes to the ignition switch. I can’t find any info anywhere as to how to hookup…any help would be appreciated.

Thank you


Here is a .pdf of the installation instructions. There seem to be loads of discussions about this system on the web. You may want to check some of them out.


Outlets Out


My 1989 280DA Sea Ray’s shore input was plugged into a 110 volt system at my house. The batteries were being pulled down all the time because I was in the process of changing out all the incandescent lights for LED fixtures, and rewiring as I went. Marinco inlet

So, I plugged a battery charger into one of my 110 outlets, and turned it on. The battery charger shorted out. After that none of the 110 receptacles worked.

I have replaced the circuit breaker on the main panel, and have replaced the GFI outlets in the boat. (One guy told me it must be the charger/converter (Professional Mariner New Pro 20/35 3 Bank) So I pulled that out where I could get a look at it. However, I get good 12 volt output from it when it is hooked to a 110v source.

I am not sure what else to do.

Any ideas? If so I would sure appreciate your advice.



Hi Ron,

I would start at the panel to see if you have AC power.

Using a meter, check for AC voltage on both the line and load side of the circuit breaker. Also, check for power when a load, such as the charger is connected. If you have power at the breaker, check at all outlets in the series as they make their way to the battery charger.

You will probably find a bad connection in the line between the ac panel assembly and the charger outlet.

Hope this helps,


Can’t Stop This Thing


I have a Crusader engine that was built in 2000 with an odd problem. The boat’s key switch will not shut off the engine and the main boat battery switch will also not shut it off.

The key swtich has been changed three times but the problem remains. I have disconnected all boat wiring add-ons. The manufacturer says check all grounds.Crusader marine engine

Will a new alternator solve the problem? The alternator has a large orange wire and a small black wire and it seems to charge properly

Thank you for any help.


Hi Stephan,

It is possible that the alternator is bad, but before replacing it, I would check for an accidental short between the ignition feed wire (usually red/purple) and the ignition wire (usually purple). The purple wire supplies power to the ignition system on the engine.

  • With the key switch off, check for 12v power on the Ignition post on the key switch.
  • Chase down the purple wire through the boat harness to the engine harness.

It is also possible that the alternator sense wire (purple ignition power) is either touching the alternator output or something has happened internally to the alternator and these to posts are internally connected.

Good luck,


Sound of Silence


I recently purchased a 2006 Chaparral 236 SSI knowing that the boat’s stereo didn’t work.

After replacing the fuses on the stereo and checking the fuse panel underneath the dash, I didn’t find any breakers popped. But, I was still not getting power to the stereo. Chaparall 236

I went ahead and bought a new stereo to put in, reconnected the wires – and still have the same issue. I am trying to figure out where to start troubleshooting next.

I have pulled out all the speakers and checked their connections and they are good. My owner’s manual doesn’t help in locating anything else I could check such as ground or the which lines go where.

If you have any tips or a place for me to start I would appreciate it.

Thanks for your time. All other electronics besides speedometer and tach are working fine (that would be another question haha).


Hi Jon,

The best way to solve this is with a handheld voltmeter and confirm that there truly is 12v power at the stereo connection when you are trying to turn the stereo on.

There is probably a loose connection or corroded wire that is causing the problem.

Hope this helps,


Gang the Grounds?


I just replaced my boat battery charger with a Guest 2622A.

After more than 24 hours, the #2 red and green lights are on, #1 is green only.

The original charger had three DC wires; #1, #2, GND. Since the 2622A has an additional ground, I jumpered the two DC- together with the ground wire from the batteries connected at DC- #2. Optima deep cycle battery

Will this affect the charger? I want to confirm this is ok before looking for other causes.



Hi John,

As long as both ground wires from the 2622 are connected to the common DC ground system it should be fine.

The 2622 is actually has two separate battery chargers inside of it so both grounds need to be connected for the system to work.

Hope this helps,


Wellcraft Shore Power Wiring


I’m trying to locate a manual for my boat, a Wellcraft Monaco 3000. Specifically, I’m trying to track down a wiring diagram for the AC shorepower distribution panel.Wellcraft Monaco

Is there any chance that you may know how to get what I need? Any leads at all would be greatly appreciated.



Hi Leroy,

I have never seen a manual for your boat. But, I believe BH Electronics produces the AC/DC panel for your boat. They may be able to help.

Good luck.


Suspect Starter

Hi Kevin,

I bought a used boat, a 1987 Sunbird with 3.0 liter engine.

I get clicking sound from what appears to be a circuit breaker mounted on top of engine. Also, the voltmeter on the dash drops a good deal when I turn the ignition key. Ignition switch

I’m not sure where to start trouble shooting.

I have had the boat out and runs good, but starting it has always been suspect as it would click then kept bumping key and finally turn over. Now can’t get it to even turn over.

Any suggestions would be appreciated. I don’t know a lot about boat wiring and marine electrical systems.



Hi Joe,

I would try temporarily bypassing the circuit breaker to see if your problem goes away.

If this doesn’t solve it, I would start at the boat’s starter. A clicking on the engine usually is a sign of a starter that is not engaging due to a bad solenoid.

Hope this helps,


Thanks Kevin,

It appeared to be the starter…I’ll know for sure when I get around to replacing it.




I have a Mako 191 that is nine years old.

The VHF radio and depth finder do not work. The boat batteries are fine and everything else in the marine electrical system works. I also checked the boat’s circuit breakers and they are fine as are the two inline fuses.

The radio and depth are connected to same switch. How do I know if it is the switch that has gone wrong, vs. other connections/wiring. And, if it is switch, how do I replace?

Thanks,Mako center console boat


Hi Sandy,

The best way to track down your marine wiring problem is with a digital multimeter. You will be looking for 12 volt power at the connector when the radio is turned on.

Since both devices have quit, it would only make sense that it is either the switch, one of the switch connections, or the ground wire.

Boat builders only use a few different switches. The most common are made by Carling Switch. If the switch is bad, email me a photo and I will tell you what kind of switch it is.

Hope this helps,


Two Pumps. One Switch.

Hi Kevin,

Thanks for all of the advice and articles. They are really helpful.

Here’s my situation.Dual automatic bilge pump wiring

I’d like to add a second automatic bilge pump to my 1985 Thompson 26. But, the old marine electrical switch panel doesn’t have any available accessory switches that I can tap into. So, could you please tell me how to set up the boat wiring to handle two automatic bilge pumps from a single switch?



Hi Eddie,

Here is a boat wiring diagram that will work for you – and it’s fully compliant with ABYC marine wiring standards.

Thanks for writing.


Boat Wiring and Marine Electrical