Kevin,

I am in the process of restoring a pontoon boat and doing some research on the fuel system.

If using a plastic fuel tank with rubber hoses that go from the tank to the metal deck fill on the side of the railings, should you ground the metal inlet to eliminate any static charge?

The U.S Coast Guard’s Boating Safety website says that any portion of the fuel system that is metallic has to be grounded. This confuses me because if you ground the inlet, it will essentially ground the entire marine electrical system, which could potentially cause corrosion issues.

Any advice you can give me would be great.

Thank you,

Bill

Hi Bill,

It is important to ground all of your boat’s metal fuel fill components together to prevent accidental, static discharge.

When fuel flows down a hose, the swirling action creates a static buildup. If the fill is not grounded to the tank, there is a change of a static discharge when the pump is removed from the fill which can cause an explosion. If the fuel fill is made of plastic, this static ground wire is not required.

Galvanic corrosion (the corrosion that occurs when dis-similar metals are electrically connected) will not be a concern. To cause galvanic corrosion, the two pieces of metal need to be electrically connected and submerged in the same body of electrolyte (water). If your boat’s fuel fill and tank are continuously under water, you have more serious concerns than galvanic corrosion.

Please let me know if you have any other questions,

Kevin

Kevin,

Thank you for quick response.

The way the boat was originally wired, there was a tank ground wire from the filler to the negative terminal of the battery.

The tank is plastic so I do not think bonding them together would discharge the static energy. The only metallic portion of the fuel system is the filler.

Is this the correct way to go about this?

Again, thank you for your help.

Bill

Bill,

Beyond connecting all metal components in fuel system that can come it contact with fuel, the system must also be connected to the boat ground.

The full intent of this practice is to give a low resistance path back to ground – metal fill – wire to tank – tank – to ground on boat – ground connected to metal underwater gear – boat in water – that will help prevent static discharge buildup.

• If your boat fuel tank has a fuel gauge sending unit, connect the static ground to the sender and the sender ground to the battery negative/ground bus.
• If your boat does not have a sender, connect the static ground wire directly to the battery negative/ground bus.

Hope this helps,

Kevin

Kevin,

This clears it all up.

Thank you very much for your help.

Bill

Kevin,

I could really use some of your wiring wizardry.

I have have a 2009 Centurion Avalanche. I put it up for winter and everything was working fine. I charged and installed the boat batteries after winter. All of the switches work, horn, stereo, pump, etc. I go to bump the key and I get nothing. The boat is still on the trailer and before I drag it to the lake I wanted to ensure that power was getting to the starter.

I made sure that the batteries are fully charged, boat battery switch is in the on position, emergency kill switch is in place, boat is in neutral…and I get nothing when I bump the key. I pulled the fuse behind the ignition switch and it looked fine.

The boat has dual batteries. The boat dealer added an marine battery switch last year as the batteries were draining even though the battery switch was turned to the off position.

The boat on has forty hours on it. After working in a confined space and pulling my hair out, I could use some expert advice.

Thanks,

Tommy

Hi Tommy,

If the instruments have power when you turn on the key, then I would check the neutral safety switch. Based on Standard Boat Wiring Colors, follow the yellow/red wire from the starter post on the key switch to the neutral safety switch in the shifter control.

If the key switch has no power, I would check the breaker on the engine that feeds power to the ignition.

If you use a voltmeter or a test light, you will be able to find the problem. It may be something as simple as wiggle the shifter a little or replacing the starter solenoid.

Hope this helps,

Kevin

Kevin,

I’m in the boat now with even less hair.

The ignition in the on position does nothing as well as the start position.

It appears that power isn’t getting to the switch. The fuse leading up to the switch looks good. I have also been playing with the shift lever to find the sweet spot, no luck.

Trying to locate the breaker on the engine.

Thanks for all of your advice, hopefully I can get on the lake today.

Tommy

Kevin,

You the man!!! It was the engine breaker.

Tommy

Kevin,

I have a 1987 Sea Ray Sorrento S-19 with a 4.3 Liter OMC Stern Drive - with less than 400 hours on the motor.

I just put the boat in the water this weekend – and experienced a slight electrical shock when touching the shifter handle after starting the engine. Given that they are slight shocks I am thinking it may be the ignition switch.

I’ve looked at the boat’s wiring as much as I could see and didn’t see anything that would suggest a short. It all looked in good shape. I also reconnected the boat battery wiring and that didnt work. 

Fuses? Ignition switch? Any thoughts?!

Thank you!

Larry

Hi Larry,

It is probably not your boat’s ignition switch.

The starter circuit goes through the shifter, but not the ignition. Since your problem is still occurring after the engine has started, I would look at connections on the engine.

Your boat motor has a shift interrupter circuit that basically connects your ignition coil to the shift cable. When operating properly, the shift interrupter will momentarily ground the coil during shifting. When not functioning properly, crazy things happen.

The shift interrupter should be on the starboard side of the engine and will have a shift cable connected to it. Chase the wiring from the negative side of the ignition coil to the interrupter to find your problem.

Good luck,

Kevin

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Hello Kevin,

I have a Wellcraft Portofino that I have owned for several years.

When I bought the boat it had an AM/FM CD player in the cockpit that worked fine. I added a car style radio to the salon about three years ago. I wired the unit properly and attached the “memory” lead to an empty, fused position on the same 12 volt bus as the cockpit radio.

From day one the salon radio would lose it’s memory on engine start while the cockpit radio did not. In between engines starts is not a problem. I double checked my wiring, which seemed good and wrote the problem up to buying a cheap radio on sale.

Midway through last season I replaced the cockpit AM/FM radio with a new Sony Marine unit. I now have the same problem with this radio! The tuner memory holds until I start engines. I just don’t get it!

The marine electrical is set up with two battery banks. The starboard bank is a 4-D and starts that engine and navigation equipment including the cockpit Sony radio. The port bank is a bank of four 6 volt deep cycle batteries wired series/parallel for 12 volts that start the port engine and also supplies the house.

I have checked all of the radio connections. I have switched the memory lead from the original fuse panel to different bus bars. Nothing has helped, as soon as I start an engine with the same battery bank the the AM/FM radio memory leads are attached to, the memories go blank.

I am starting to think that this is a surge problem. I believe I have confirmed this by using my master boat battery switches to start engines on the battery bank that does not have the radio memory. If I do that there is no memory loss. Starting and running my boat in this manner is not practical for me and leaves open the possibility of draining the wrong battery bank.

This situation is really starting to drive me nuts, I’d greatly appreciate any recommendations you may have.

Thank you,

Michael

Hi Mike,

Stereo memory circuits are sensitive to low voltage and you are suffering for a voltage drop “stack up” and will reset after only a few milliseconds of low voltage. This is very common with newer, higher draw, higher tech stereos.

The power feed to your helm has a drop. The more current that you draw through it, the more the voltage drop in the circuit. When higher draw devices such as bilge blowers, cockpit lights, stereos, the voltage drop is even higher. Slightly corroded connections induce voltage drops. When you start the engine, the source voltage (the battery) drops lower which makes the stereo input voltage that much lower.

Solution:

• Increase the size of the power feed wiring and ground to your helm panel.
• Run a dedicated power and ground lead from the battery to the stereo.
• Make sure you use circuit protection at the source of power. An increase of 0.1 volts will mean the difference between the stereo memory resetting and remaining.

Hope this helps,

Kevin

Kevin,

Here is a boat wiring diagram for the marine electrical on my 2008 Clearwater 2200WA with a 225HP Yamaha.

I have a two battery configuration where one is used for starting and the other is the house battery for electronics and the like. I have both boat batteries connected via a dual circuit marine battery switch (5511e) and both batteries are charged via isolated leads from the outboard since this outboard provides an accessory charging lead in addition to the primary lead to the starting circuit.

I keep both batteries off via the battery switch when the boat is not in use and the only direct wiring to the battery is for the bilge pump float switch.

The other day, I could not start the motor because of a discharged starting battery after the boat had sat for several days. I switched to the combine mode and the motor started. Ran all day with no issues.

Two questions, please: Is there a problem with the boat battery wiring or charging circuit? Will this circuit accommodate a battery charger if the boat battery switch is in the off position?

Thanks.

Frank

Hi Frank,

This is a great marine electrical system and the dual circuit PLUS battery switch is one of the key components. My best guess on the dead battery would be the device that is connected to the mystery red lead connected to your starting battery (at the switch). It is probably a stereo memory wire or some type of memory device.

With the switch in the off position, you will need to use a dual output battery charger or manually connect your charger to one battery and then to the other. If you are installing a dual output charger, I strongly recommend connecting the battery at the switch and your ground bus and not at the battery. Too many battery connections become confusing and the mix of small and large wires on the terminals always causes a loose connection.

Hope this helps and nice wiring diagram,

Kevin

Hello Kevin,

I have a 1989 Four Winns Liberator 201 with a 350 OMC motor. I pulled the boat out of winterization today and wanted to check everything before I put the boat in the water.

When I went to hit the boat horn to test it, the horn sounded weak and eventually faded and did not work.

Next the navigation lights would not turn on. But when I hit the horn, the lights will turn on until the horn is released then they go off. Not sure if it could be a bad ground or short in the wiring.

I removed the access cover and found someone has cut and spliced wires on the boat before. There are also some wires disconnected and zip tied up and others just cut.

The boat blower motor did work when starting the boat but now it also will not turn on. I’m not an expert in marine electrical by any means but would like to find the issue my self. I have a voltmeter but never used it other than checking glow plug relays on diesel engines. I have used a test light on trailers – checking for power and such so I do have a little knowledge but not where to start on this project.

Any help would be great.

Thanks

Mark

Hi Mark,

I’m a HUGE Liberator fan. I worked at Four Winns during the era after their production.

There are few marine wiring items to check since several things have quit working.

• Main engine plug – round plug 1 1/4″ diameter on the starboard side of the engine. Unplug and check terminals
• Boat harness ground – check ground connection on rear bell housing of the engine
• Helm fuse block – check ground and power leads on the main fuse block under the helm

Once your find the corroded connection, replace as necessary.

Good luck,

Kevin

Kevin,

Thanks for all of your great boat wiring advice.

Last year when I purchased my boat, a 2006 Centurion Enzo, I had the a Perfect Pass installed. To do so, as is common practice with these boats at least, the gauge which is essentially a blank with some power run to it for lights I would assume, is removed and the Perfect Pass gauge is installed in that location.

Well the marine electrical installer apparently took those four hot wires and taped them together and stuffed them back in the dash. Couple of times last year while we were out, I could occasionally smell what I knew was an electrical fire, but thought that it was my switches that I run my ballast pumps through. I was not using a relay and the pumps pulled just about as many amps as the switch was rated to handle. I just assumed that the switches were failing.

As boating season approaches, I have been spending some time cleaning up the horrible marine wire runs from the Perfect Pass install and in doing so I came across the source of what I am pretty sure is the source of my fire smell. It appears that the wiring wore through the tap or the tape came off and the wire was contacting the metal brackets that holds the gauge into the dash panel. You can be the judge by looking at the attached pictures.

Anyways, my question is what do I do with these wires and how do I properly and safely dress them to prevent a future catastrophe. Unfortunately pulling a fuse doesn’t seem to be an answer because all to the gauges seem to be off the same power run.

Thanks.

Mike

Hi Mike,

The best solution would be to trace the wires back to their source and remove them completely. The main one to remove would be the purple, in standard boat wiring colors, this is the ignition power lead.

If you simply tape them up again, the same problem will eventually happen again.

Happy boating,

Kevin

Believe it or not, the electrical system in your boat faces a foe more sinister than the ravages of time or the harshness of the marine environment. Your electrical system’s greatest nemesis might be staring back at you in the mirror each morning as you brush your teeth.

Yes, you. Joe Saturday. Mr. DIY.

You see, in a former life, I was a parts guy. I worked in parts stores and a GM dealership for more than 10 years. I have met Joe Saturday and he is evil…

As you can tell, Brett’s a good writer and his advice is excellent. Give it a read.

Hello Kevin,

My question is regarding marine wiring.

On my marine electrical, I’m using an isolation transformer in order to transform 220V to 110V.

Recently, the boat’s reverse polarity indication light is on. I’ve opened the circuit to see how this indication is measured and saw that there is a diode and led connected between the neutral and the ground.

I’ve realized that in the current situation the output of the transformer is basically floating, therefore the neutral line can have any voltage. One of the solution that I’ve seen online is connecting the neutral line at the output of the transformer to the boat’s ground (that is not connected to the shore’s ground). So I have several questions about it:

1. Is there advantage in connecting the neutral to the boat’s ground over working with floating voltage?
2. Is it ok to make this connection?
3. For about a year, the indication was off, what can be the cause for it to be on now?

Thanks in advance,

Ilia

Hi Ilia,

At the source of power, the neutral must be connected to the ground. With an isolation transformer, this is on the output (boat size). Please connect the output neutral and ground together immediately. It is an extreme shock hazzard as is.

The reverse polarity indicator is connected to the input side of your transformer. With an isolator transformer, the light is more of a nuisance than a concern. It is telling you that the polarity is reversed (Neutral is hot) on the input. Since you have an isolation transformer, you really don’t care as long as the neutral and ground are connected together on the output side.

Hope this helps,

Kevin