Need help/ advise for creating complete new wiring system.

I need to rewire my jet boat in my profile picure. Need help selecting the proper fuse block to be placed under the dash. The bigger the better, and I would like to know how big of a circuit breaker would be needed to attach to a #8 size positive wire from the engine compartment to the dash area that would end at a buss bar. I plan to use two buss bars, one for positive and one for negitive # 8 wires to these. I would wire in a fuse block to keep everything else fused to prevent the meltdown I had happen this summer.

My boat does not have a stereo, but I would like to add navigation and anchoring lights and one 12 volt power source in the dash.

I do have instrument gauges in the dash for water temp, oil pressure, volt meter, tachometer, and one fuel gauge to monitor two saddle tanks switchable in dash - has electric solenoid to select between tanks.

Any good advise would be welcome.

Thanks,

Mikes402jetboat

Re: Need help/ advise for creating complete new wiring system.

Here are a couple of links to good help...
http://forums.iboats.com/forumdisplay.php?f=23
or
http://www.google.com/search?client...ource=hp&q=Boat+Electrical&btnG=Google+Search
It's all a logical process. Find the load, decide the wire size for the load and it's run distance, fuse correctly. Assemble with appropriate connectors and methods.
You probably want tinned wire in your project, it is much more resistant to corrosion than plain.
Have fun & good luck. Wiring is one of those things I actually enjoy doing.
I hope you enjoy it as well.
Best of all you KNOW what was done.

Re: Need help/ advise for creating complete new wiring system.

I found some wiring harnesses here on iboats, not what I needed but it might work for you.
As for buss bars, I use one for the grounds and use the fuse block for hot.
Indoards use a circuit breaker at the engine, you might find that here too.

I like a 'clean' wiring system that's easily expandable!

Look around on the forum, I have seen some nice basic wiring diagrams....it may be a 'sticky'!

Re: Need help/ advise for creating complete new wiring system.

Mikes402Jetboat said:

I need to rewire my jet boat in my profile picure. Need help selecting the proper fuse block to be placed under the dash. The bigger the better, and I would like to know how big of a circuit breaker would be needed to attach to a #8 size positive wire from the engine compartment to the dash area that would end at a buss bar. I plan to use two buss bars, one for positive and one for negitive # 8 wires to these. I would wire in a fuse block to keep everything else fused to prevent the meltdown I had happen this summer.

My boat does not have a stereo, but I would like to add navigation and anchoring lights and one 12 volt power source in the dash.

I do have instrument gauges in the dash for water temp, oil pressure, volt meter, tachometer, and one fuel gauge to monitor two saddle tanks switchable in dash - has electric solenoid to select between tanks.

Any good advise would be welcome.

Thanks,

Mikes402jetboat

Click to expand...

you want to carry your battery cables(#8 wires) up to the dash? why?

Re: Need help/ advise for creating complete new wiring system.

You don't need a positive bus bar. The postive feed from the battery terminates at the fuse panel. Individual circuits branch out from there. And why the emphasis on as "bigger is better". You don't have that many electrical loads. And why are you even doing this. The stuff you want to add is insignificant from a load standpoint. Add it using in-line fuses. No need to totally rewire a boat unless there is some major underlying reason the existing wiring is unsafe or problematic.

Re: Need help/ advise for creating complete new wiring system.

NHGuy said:

Here are a couple of links to good help...
http://forums.iboats.com/forumdisplay.php?f=23
or
http://www.google.com/search?client...ource=hp&q=Boat+Electrical&btnG=Google+Search
It's all a logical process. Find the load, decide the wire size for the load and it's run distance, fuse correctly. Assemble with appropriate connectors and methods.
You probably want tinned wire in your project, it is much more resistant to corrosion than plain.
Have fun & good luck. Wiring is one of those things I actually enjoy doing.
I hope you enjoy it as well.
Best of all you KNOW what was done.

Click to expand...

Thanks for quick response to my questions, and thank you for the links to some diagrams. I appreciate the fact you took some time to reply back to me.

Mike

Re: Need help/ advise for creating complete new wiring system.

1fishbone said:

I found some wiring harnesses here on iboats, not what I needed but it might work for you.
As for buss bars, I use one for the grounds and use the fuse block for hot.
Indoards use a circuit breaker at the engine, you might find that here too.

I like a 'clean' wiring system that's easily expandable!

Look around on the forum, I have seen some nice basic wiring diagrams....it may be a 'sticky'!

Click to expand...

Thanks for the tip on the negative buss bar is only needed, and positive wire to the fuse panel only. I am a newbie when it comes to rewiring this jet boat, I wanted to try to give as much circuit protection I could, instead of just replacing fried wires with new ones, and hope it holds up.

I did buy a book named "The 12 volt bible for boats" to try to get all the information on figuring out the AMP load I might use and the correct Marine tinned AWG wiring size I would need to support the new items I wanted to install.

My original wiring did not appear to have any fuse panel or circuit breakers built into the wiring anywhere. Not even an On/Off switch for the battery. The only on/off was at the dash key switch.

The boat was purchased about 3 years ago, I bored out and completely rebuilt the engine and heads in 2010 and managed to get 3 hours of run time on it before the melted wiring issues cropped up.

All wires going to the starter were fused together, except the main battery wire. I removed the key switch and the switch tested out fine, the wires to the starter and solenoid apprear to have been spliced before with butt connectors and nothing there was color coded correctly.

I removed the back bench seat and passenger front bucket seat and side apholstry to get to the wiring, and found more melted wires along the gunnel area. This is what made me decide to redo the whole wiring system instead of taking chances burning my boat up on the lake.

I have alread purchased some of the marine tinned AWG wire in #10 size
(100ft) in both black and red colors. I also bought 25 ft of #8 Orange Marine tinned wire just for the alternator wire. I bought a new one wire 105 AMP Marine Delco style alternator to replace the NON marine type that came with the boat. Since the alternator sits low, right next to the port saddle tank, I thought it might be a good idea to get one that can't spark out on me.

I was thinking that #8 AWG tinned cable should be run up to the fuse panel based on possible wiring needs in the future, is this wire size overkill? If so what would you recommend for the correct size wire to run from the battery/starter solenoid connection to the fuse panel?

Re: Need help/ advise for creating complete new wiring system.

You have the right idea about the alternator. Non-spark protected ones are a violation and a safety hazard.

Unless you are planning to add a lot more electrical devices to the fuse block than you've listed, 10 gauge wire should be perfectly adequate, not to mention easier to work with and cheaper.

Re: Need help/ advise for creating complete new wiring system.

Silvertip said:

You don't need a positive bus bar. The postive feed from the battery terminates at the fuse panel. Individual circuits branch out from there. And why the emphasis on as "bigger is better". You don't have that many electrical loads. And why are you even doing this. The stuff you want to add is insignificant from a load standpoint. Add it using in-line fuses. No need to totally rewire a boat unless there is some major underlying reason the existing wiring is unsafe or problematic.

Click to expand...

I meant the bigger the better for the fuse panel, so if I needed to add higher amp items in the future I would have the fuse capability to do so.

I am a newbie doing this wiring job, and in Missouri I could not even get the local marina's to discuss my wiring issues because it is a jet boat. They refuse to give any advice on parts, or do any work on the boat because it is a "jet boat".
Last year I replaced my entire steering system myself, and removed and replaced the engine from home in my shop as l could not get any assistance. My boat did not come with a manual, nor a wiring diagram for me to follow, and I have never done elecrical wiring in the past. The boat is a 1976 Starbuck jet boat with a 402 chevy big block / Berkeley 12JC jet pump. The company is no longer in business, and manuals do not exist for this boat.

Since I had three strikes against me already, with no hope of even getting advice...I came here for some advice. I did buy a book "The 12 volt bible for boats" it has some information about AMP loads and wiring distance/ wire size's needed. Perhaps I over estimated how many AMPs were going to run down the wire to the fuse block, which is why I was going to run # 8 Marine tinned wire to the fuse block. I did not plan to run my battery cables to the dash. I am adding a Perko on /off switch at the battery. I wanted to run an extra line from the starter/battery connect forward to be able to fuse my circuits to prevent future shorts that melt thing down. If # 8 AWG is overkill from the starter/solenoid to the fuse panel what to you recommend for this.
I am just guessing, and trying to figure in a line large enough to carry a big load if needed.

I am also replacing ALL the wire because of the age of the wires, and my dicovery of melted wires in the starboard gunnel and in the starter area. I will have to yank the starboard tank to get the wiring out, so I might as well just redo all of it now, so I know what is actually back there behind the tank. Wiring in front of the tank to the dash didn't look good at all.

Thanks for taking the time to ask.


Mike

Re: Need help/ advise for creating complete new wiring system.

NYBo said:

You have the right idea about the alternator. Non-spark protected ones are a violation and a safety hazard.

Unless you are planning to add a lot more electrical devices to the fuse block than you've listed, 10 gauge wire should be perfectly adequate, not to mention easier to work with and cheaper.

Click to expand...

Thanks for that advise, and since I already have the marine tinned AWG wire from Genuinedealz.com I will use that instead of the # 8 AWG I was going to use.

I went to Cabella's in Kansas this after noon and was able to get some other advice from "Mike" at the service shop. He stated the guages can be powered up from the ignition switch, and would not need to go throught the fuse panel. I plan to take that advice to heart and wiring it accordingly.

Thanks for all the input, and hope to hear from you again, if I might run into any other questions not spelled out in The 12 bible for boats book I bought.

Mikes402jetboat - Im Missouri - Pronounced Misery

Re: Need help/ advise for creating complete new wiring system.

Rewiring and the fact that you own a jet boat has absolutely nothing to do with each other. The engine has a charging system. The drive (prop or jet) does not contribute to that. The folks you've been talking to obviously don't have a clue so you've come to the right place. But back to the wiring. You still don't need a positive bus bar if you rewire from stern to bow. You do need a fuse or breaker panel that has that built in. A ground bus is desired but it too may be built into the panel. Figure out what you need switches for, what you have now, what you "might" add in the future, and that will detemine how many switches and how many fuses/breakers you need.

Be aware that there are two electrical systems on a boat. 1) one system runs from the engine to the helm. That system powers the instruments and controls engine starting. 2) The "boat" system runs from the battery to the helm (fuse/breaker panel) and then branches out to feed the lights, radio, fish finders, interior lights, etc.

Re: Need help/ advise for creating complete new wiring system.

I used one of these Blue Seas [URL="http://bluesea.com/products/5026"]fuse blocks[/URL] when I rewired my boat and it's pretty nice. (This is a screw terminal fuse block, but they have spade terminal blocks too.)

My Mercruiser wiring harness has a 10ga wires for the connections to the fuse block (and a 50 amp breaker at the engine for the 10ga wire going to the helm). The usual loads (lights, radio, etc) are fine with the 10ga main power wire, but I wouldn't run a big stereo off it. The 8ga wire you have is fine for wiring up the fuse block, but kind of over-kill.

I'd defiantly use some heavy gauge wire for the 105 amp alternator and terminate the alternator + connection at the starter, I used 6ga when I added a 100 amp alternator. If you have an ammeter, get rid of it and switch to a volt meter. An ammeter requires the alternator's + lead to connect directly to the ammeter gauge, not something you want to do with a high output alternator. (If your 105 amp alternator was pushing a bunch of current to the ammeter..... it could have melted wires.)

There is a standardized marine wiring color code and manufacturer's (IE: Mercruiser) have their unique wiring diagrams for the engine. If your jet's wiring is such a mess that you can't make heads or tails of it, I'd try to follow one of the manufacturer's wiring diagrams as they should come close to all the systems you need to wire up, alternator, ignition, starter, etc..

What ever you do, make sure to use different colored wires (red, blue, purple, pink, yellow, etc.) for the different circuits.

Re: Need help/ advise for creating complete new wiring system.

Mikes402Jetboat said:

He stated the guages can be powered up from the ignition switch, and would not need to go throught the fuse panel. I plan to take that advice to heart and wiring it accordingly.

Click to expand...

That is bad advice. Every wire should be from a fused circuit. There should be a heavy gauge wire that goes up to your panel from a circuit breaker near your battery. from your fuse panel there should be a fused wire that goes to your ignition which can also include your gauges.

Re: Need help/ advise for creating complete new wiring system.

Here is a generic wiring diagram, courtesy of Silvertip. Note that the gauges are indeed powered by the ignition switch. The ignition circuit needs its own fuse. Also note that the main circuit breaker/fuse isn't shown; it goes between the master switch and the battery positive terminal.

Re: Need help/ advise for creating complete new wiring system.

Bubba1235 said:

My advice, use your boats manual and wire it back to factory specs. it'll save you all sorts of heaqdaches in the future when someone has to work on it.

Click to expand...

I bought the boat on eBay 3 years ago, it was built in Colorado by Starbuck in 1975 and I don't have a manual. Nobody in Missouri or Kansas will even touch a jet boat. So, I have made my own wiring harness design on my computer using Paint last night. I incorporated a fuse panel into the front of the boat to fuse my ignition, bilge pump, lights, 12 accessory outlet. Could any of you electrical guru's take a look and give any advice you might have for me please?

Mikes402jetboat

Re: Need help/ advise for creating complete new wiring system.

fishrdan said:

I used one of these Blue Seas [URL="http://bluesea.com/products/5026"]fuse blocks[/URL] when I rewired my boat and it's pretty nice. (This is a screw terminal fuse block, but they have spade terminal blocks too.)

My Mercruiser wiring harness has a 10ga wires for the connections to the fuse block (and a 50 amp breaker at the engine for the 10ga wire going to the helm). The usual loads (lights, radio, etc) are fine with the 10ga main power wire, but I wouldn't run a big stereo off it. The 8ga wire you have is fine for wiring up the fuse block, but kind of over-kill.

I'd defiantly use some heavy gauge wire for the 105 amp alternator and terminate the alternator + connection at the starter, I used 6ga when I added a 100 amp alternator. If you have an ammeter, get rid of it and switch to a volt meter. An ammeter requires the alternator's + lead to connect directly to the ammeter gauge, not something you want to do with a high output alternator. (If your 105 amp alternator was pushing a bunch of current to the ammeter..... it could have melted wires.)

There is a standardized marine wiring color code and manufacturer's (IE: Mercruiser) have their unique wiring diagrams for the engine. If your jet's wiring is such a mess that you can't make heads or tails of it, I'd try to follow one of the manufacturer's wiring diagrams as they should come close to all the systems you need to wire up, alternator, ignition, starter, etc..

What ever you do, make sure to use different colored wires (red, blue, purple, pink, yellow, etc.) for the different circuits.

Click to expand...

I stayed up very late last night until morning creating a Marine color coded wiring diagram that I uploaded, after doing so the diagram looked fairly small and hard to read...it printed out too small as well. I'm going to try uploading it again and would appreciate it if you could take a look and give me an opinion about it. The 100 AMP alternator has not been installed in the boat yet, so it was not the reason for the melt down I had. The 105 AMP rating would be at high RPMs only from what I can read about it. Looks like it will be around 58 AMPs at an idle and increases Amperage with RPM increases. The motor is a 402 Big block Chevy recently completely rebuilt in 2010 and I doubt if it will be running much over 4500 to 4700 RPMs even though I had the machine shop build it to be able to handle 6000 RPMs sustained. It was bored 040 over, new Keith Black 10.5 to 1 pistons and Eagle H racing rods. I also had it balanced and the heads completely rebuilt. Large oval port heads with Crane roller rockers and heavy springs.

Back to the wiring, if you could please check out my diagram and see what you think please. If you can't read it due to size limitations on this site, I could send it to you at your regular email address if you are comfortable with sharing that with me.

Thanks for your time, and replying to my thread about this.

Mike - Mikes402jetboat
EDIT

Re: Need help/ advise for creating complete new wiring system.

Looks pretty darn good, but....

Tooooo much 10ga wire, 10ga for a bow/anchor lights, bilge pump, gauge lights, etc? 14 or 16ga would be plenty. (FWIW, my trolling motor uses 10ga wire inside, to the motor. That puppy is carrying some serious current, 24V x 40 amps) 10ga is overkill for most of the wiring and will be a real pain since it's so large and hard to bend.

A terminal strip (for ground wires) at the transom will help clean up the ground wires. I have 5-6 ground wires (low current) on mine, then a 12ga wire going to the engine ground.

You should have a breaker (50 amp?) at the engine, between the starter's + lug and the fuse panel's + supply wire.

If you are going to use lighted switches, you will need a ground wire to each switch for the light inside the switch. The light's + wire goes to the load (switch output), so the switch's light comes on when the device is on.

Fuse ratings too high, bow/anchor lights 5 amp (?), bilge pump should be 3-5 amp (depends on pump draw), ignition? The fuse shouldn't be higher than the wire can handle, but can be smaller to protect the device attached.

Why only a 6 slot fuse panel (copy-n-paste from ST's diagram?)? Add a stereo, some coutesy lights and the panel is maxed out. I installed a 12 slot and filled it up,,, had to put all 3 of my fish finders on 1 circuit/fuse...

Since you are modernizing the wiring, a kill (dead mans) switch in the ignition circuit would be a nice touch. Even though you might not use it all the time, it would be nice to have if you were in really bad water, keep you from getting run over if you were tossed out of the boat.

Re: Need help/ advise for creating complete new wiring system.

fishrdan said:

Looks pretty darn good, but....

Tooooo much 10ga wire, 10ga for a bow/anchor lights, bilge pump, gauge lights, etc? 14 or 16ga would be plenty. (FWIW, my trolling motor uses 10ga wire inside, to the motor. That puppy is carrying some serious current, 24V x 40 amps) 10ga is overkill for most of the wiring and will be a real pain since it's so large and hard to bend.

A terminal strip (for ground wires) at the transom will help clean up the ground wires. I have 5-6 ground wires (low current) on mine, then a 12ga wire going to the engine ground.

You should have a breaker (50 amp?) at the engine, between the starter's + lug and the fuse panel's + supply wire.

If you are going to use lighted switches, you will need a ground wire to each switch for the light inside the switch. The light's + wire goes to the load (switch output), so the switch's light comes on when the device is on.

Fuse ratings too high, bow/anchor lights 5 amp (?), bilge pump should be 3-5 amp (depends on pump draw), ignition? The fuse shouldn't be higher than the wire can handle, but can be smaller to protect the device attached.

Why only a 6 slot fuse panel (copy-n-paste from ST's diagram?)? Add a stereo, some coutesy lights and the panel is maxed out. I installed a 12 slot and filled it up,,, had to put all 3 of my fish finders on 1 circuit/fuse...

Since you are modernizing the wiring, a kill (dead mans) switch in the ignition circuit would be a nice touch. Even though you might not use it all the time, it would be nice to have if you were in really bad water, keep you from getting run over if you were tossed out of the boat.

Click to expand...

Thank you for the reply, and wiring information fishrdan!
I will definately size down the wires based on your recommendations. I have never done electrical work before, let alone tried to design a complete boat wiring diagram before.
I am actually going to use a 8 slot fuse panel instead of the 6 that is shown, but found the one out here to copy for what I needed for now. I still have two open fuses for a stereo and ? for later in that 6 fuse block shown, if I ever add anything else. This is a 65+ MPH jet boat with a Big Block Chevy and 12 JC jet pump in it, fast enough to scare the cra# outa me and my 3 extra passengers...anyway it's not your average fishing boat. (I already have a 66 Glastron with 100HP merc for fishing and tubing and water skiing). I don't really plan to add more electrical than what I have now, because even if you added a stero, you would never hear it with the 4 inch over the transom water inject headers blasting away back there! LOL.

I would have to add another battery to my Perko switch to ensure I didn't drain the battery if I used a stereo while beached.

Thanks for the tip on the size of the breaker to use...I was planning on adding something in there, but until I have the boat running again and can actually get a reading on my total AMP draw it's kind of hard to know what's right or wrong for an electrical newbie.
By the way...where I live, I could not get any advise from any of the boat shops...once they find out it's a jet boat they all clam up. They won't work on them, or even give any wisdom or advice for fear of a law suit....pretty stupid if you ask me. After all, they have been making boats with V8 big blocks in them for many years. who cares what propels them through the water! It doesn't have anything to do with the wiring... I bought the boat about 3 years ago, it didn't come with a manual or a wiring harness diagram.
Once the wiring fried along the starboard gunnel and solenoid area this summer, I figured it was time to be safe and just figure it out and replace all the wires with new Marine AWG tinned wire in the correct color codes as outlined in the ABYC standands. I just want to do this once, correctly and cleanly so if they are any problems down the road, I will at least be confident the wire colors and sizes are right to keep me out of trouble.

Thanks for all the information, it is very helpful to me and I am in your debt!

I liked the idea of the dead man switch for the ignition even though this is strickly a lake boat, I'll look into that.

I can easily update the Paint document with the right size AWG wire numbers, and add that 50 AMP breaker in there too. I plan on printing a copy of it when I get it right on photo paper, and have it laminated so I can put it in the boat under a seat for troubleshooting any future issues.

Thanks again!

Mike

Re: Need help/ advise for creating complete new wiring system.

Hey Mike,

Check out this wire size calculator, it will help you select the correct size wire.

http://beta.circuitwizard.bluesea.com/

IE: for the bilge pump wire I input;

- 12V
- 5 amps
- 30' of wire (total length of wire run, + and - wires)
- 10% drop
- fixed load

and the calculator spit out 18ga wire. Though, the note suggests that 16GA wire should be used per AYBC.

When I rebuilt my boat I had to go through all the wiring and I'd say 75% of the stock wiring was either 16 or 14ga wire. Very few wires were heavy gauge, alternator, battery, ignition, lighter. (Though I did add in a bunch of heavy gauge wiring for trolling motors, TM batteries and an onboard charger,,, stuff you won't have on your rig)

Re: Need help/ advise for creating complete new wiring system.

Mikes402Jetboat said:

If 8 AWG is overkill from the starter/solenoid to the fuse panel what to you recommend for this.

Click to expand...

Just scanned through this lengthy thread, but have a couple thoughts... On the above, my boat has 12AWG with 30A fuse which works fine for my loads. But you said you already bought the 8 and 10 AWG... so I'd go ahead and use it. If you have it on hand, why not? Also try These guys for an alternative to fuse blocks... I was very happy with my custom breakerized panel from them.

Good Luck!