Rewire engine ( warning long post )

[seapadrik]

I am reinstalling the engine down at the boat and since i pretty much redid everything else. I want to make sure i have all the bases covered.

I have included a bunch of photos ( hosted offsite on flikr ) and some notes. Based on that i have some questions regarding wires, voltemeter and the like.

Here are the notes:

### Background Information with photos/notes ###


* * Battery Box * *

http://www.flickr.com/photos/28554500@N08/9079715501/

# Large Reds from Perko switch, white wire on battery 1 from fusebox at instrument panel,
green wire on negative post of battery 1 i believe is a ground from the accessory bus. large black wire on battery one leads to engine compartment and i believe in the past was attached to rear housing of engine. other wires are for my guest battery charger

* * Cabin view of Perko switch/accessories * *

http://www.flickr.com/photos/28554500@N08/9081939154/

# Perko off/1/2/all switch plus, Ericson panel for accessories, and a bilge pump switch.

* * Bulkhead view of Perko switch/accessories * *

http://www.flickr.com/photos/28554500@N08/9081940710/

# accessories go to a box and then to individual devices. Bilge switch at top makes it way to battery 1.
# Perko red cables fort battery 1, battery 2, and finally engine compartment near starter.

* * Cockpit view of instrument panel * *

http://www.flickr.com/photos/28554500@N08/9081939888/

# Ammeter, oil pressure, Temperature, ignition switch, bilge switch , choke

* * Cockpit locker view of instrument panel * *

http://www.flickr.com/photos/28554500@N08/6093755821/

# Temperature and Oil pressure are daisy chained along with ignition to a fuse, which then connects directly to battery 1. Bilge switch also uses the fuse setup to get to battery 1 is standalone and not connected to ignition.
# Ammeter is there on far right, but appears to not be hooked up at all.

* * Engine compartment view * *

http://www.flickr.com/photos/28554500@N08/3593831549/sizes/o/in/photostream/

# Bilge Blower attached to its blue wire and apparently its grounded to the engine
# Battery 1 black cable grounded at aft housing
# Green wire at rear housing attaches to shaft brush grounding strap
# Red perko cable attaches to starter
# Alternator attaches to Starter
# green wire temp sender in head
# red wire oil pressure sender
# white wire attaches to starter
# black wire attaches to positive coil



####### Questions ################
1. Is it safe to say i should replace the current wire going from ignition to positive lead of coil with the 12 gauge yellow/red wire that i read about ?

2. If i replace my existing ammeter gauge in the instrument panel ( which i am going to do ). What will then be the wiring for the voltemeter ? one lead goes to battery for power and the other ?

3. That current bilge blower just seems to go to the switch at intrument panel, and then just ground off at the engine. is that normal ? what color and gauge wire for bilge blower ?

4. There is no 40 amp fuse on the existing red wire coming from perko switch to the engine compartment near starter lug. Where do i get those and can i attach it to existing wire ?

5. Do any of you have the grounding strap attached to the prop shaft as I do ? What is its main purpose ?

6. What items should be directly grounded to the engine ? it looks like in my setup only battery 1 has a ground going to engine.

7. it seems at most of my thru-hulls there are some wires attached to the bronze with a steel strap. Are these just good places to ground certain devices ? i notice at my main thru hull by my sink there are a few wires strapped there.

8. What gauge wire should i use to connect the alternator ( i have the 55 amp one that Moyer sells ) to the starter solenoid ?

Those are my initial questions. One more thing i have a proper crimp tool and if you have any reccomendations on perhaps bettter connections to some of these fittings let me know.


Thanks in advance and sorry for the long thread. But i wanted to have my ducks in a row and proper documentation before i posed my questions.

Patrick

[ndutton]

Patrick,

How pristine do you want to make this? I'm having a facial tic over wire colors, multiple grounds on the engine, wires not bundled neatly, household shore power breakers in a steel enclosure, gate valves, corrugated hose with cuffs going to thru-hulls and so on.

I'm not trying to be picky or critical but it seems to me you're trying to redo and clean up and depending on your goal with the electrical, this can be minor or wholesale replacement or somewhere in between.

For example (I don't think he'll mind) look at these before and after pictures of systemek's engine rewire in the first post of this thread. Is this your goal?

[seapadrik]

Hey Neill,

I am looking to do the right thing here. I have no problem replacing every wire on that engine, at the instrument panel or in the battery compartment.

I would prefer to deal with any "accessory" stuff for a phase2 type deal.

Also, if you see anything with that AC power that makes you cringe please share it with me. Safety is my primary goal. Then of course a clean and proper wiring job that I can understand.

Regarding the gate valves, i am getting hauled out this summer adn will replace those.

Please share your thoughts.

[ndutton]

I'd take on the engine wiring first. Ezra and I did his in a day, a complete new harness from instrument panel to the engine. All the wire was new, properly color coded following ABYC specs, butt splice free and contained in split loom.

We took measurements on the boat, made a loom tool out of a 2 x 12 using nails at the measurement points and laced a new harness on the tailgate of my truck (leaving the ends long). We then tied it up in split loom and took the new harness to the boat. Attaching it to the structure with Ty-wraps was first, then cutting and terminating the ends so they ran and fit nicely. We even had time for a very nice lunch in the middle of it all.

From what I could see the current color scheme is way off making future troubleshooting a nightmare. For that reason alone I'd go for the full Monty and replace the engine harness in its entirety. When you're done you'll have undamaged wire properly color coded and secured, free from splices and it will match at least one of the wiring diagrams available in the Drawings and Schematics forum category. If there isn't a diagram there to your liking we can tailor one to your needs, just say the word.

I hope Ezra chimes in on this to provide his perspective. I think he'll say it was intimidating at first but when it was done it was really no big deal.

Here's a link to the ABYC color code for wiring: http://www.acbsphl.org/Tips_and_hints/ABYC_Wiring.htm
and the Moyer Engine Wiring diagram: Moyer Engine Wiring.pdf
Two modifications you'll make to the diagram are omit the ammeter and orange 8 gauge wire going to and from it and instead use a short 4 gauge wire from your alternator output to the large starter post. If you have an electric fuel pump we'll have to tweak the diagram a little further. Alarm system? More tweaking but these modifications are easy. Bilge blower wiring should be added to the harness too so it's all bundled neatly.

[TomG]

Regarding the gate valves, i am getting hauled out this summer adn will replace those.

Please share your thoughts.

Padrik, I just replaced all my old thru-hulls and valves with proper seacocks. I used the guide posted by MaineCruising here: Replacing Thru-hulls. I was dreading this task, but as it turns out, it has been one of the easiest and most satisfying of this lengthy refit I've been doing. Access for me has good on two and bad on one thru hull. I went from 1/2" to 3/4" thru hulls and seacocks. Two tools I found indispensable were my Dremel SawMax



and a Step Wrench.



I actually spent more time working on the backing plates than anything else.

As for the wiring, do it right, cry once as Dave Neptune says.

[seapadrik]

Neil,

Sounds good. I will take on the engine wiring first.

I found the split loom you talked bout:

http://www.cabletiesandmore.com/blackloom.php?gclid=CMzGjr_l8bcCFcN_QgodwGgA_w

I haven't created a harness before , but if i am getting your gist we just want one form of transport ( the wires inside the loom ) from the panel to the engine compartment.

Keeping the task tied to my instrument panel of:
voltmeter, oil pressure, temperature, bilge blower, ignition

I assume I would assemble those wires:
Brown w/Yellow of ? gauge > bilge blower
Tan of ? gauge > head sender
Lt. Blue of ? gauge > oil pressure sender
purple of ? gauge from ign > positive coil

is there a second line from ignition switch of yellow/red to starter ?

In my photos I uploaded it shows all those instruments going through a fuse bus, then sharing a duplex cable to the battery 1. Is that cool ? or some other means is better ?

Also, I do have electronic ignition.

In the Moyer diagram there is a 40 fuse amp inline with the red 8 gauge connection from battery > starter lug. How do I make that happen ? where would I put the fuse ? Back at the Perko ? Near the starter lug ?

@ Tom thanks for the tip on thru-hull. Depending on situation i may pay for that service but will wait and see how I feel.

Thanks

[ndutton]

The 40 amp fuse in the Moyer diagram is there to protect the charging circuit and is sized for the standard Motorola 35A. Yours being a higher output would require a larger fuse if you choose to have one. I don't. The elimination of the orange 8 gauge wire by dropping the ammeter also eliminates the fuse within.

Depending on harness length, all wires can be 14 gauge with the recommended exceptions of the red hot and white starter that I prefer to be 12 gauge. As said in my previous post, the alternator output goes directly to the starter post with 4 gauge wire.

If you like I'll work on a harness drawing for you including lengths. The split loom allows you to have wires exit where they're needed. Mechanical fuel pump? No alarm system? Tachometer?

[Dave Neptune]

Fwiw

Patrick, I just did a rewire on mine. I did all of the main power to switch, switch to 3 panels and the entire engine.
I did not wire the engine as convention would dictate. Rather than have 2 sets of wires going aft for the main panel and the engine, I took a #6 wire to the panel and from there 18" away a #10 to the engine panel for it's power. Doing so really cleaned up a lot of the wiring.
I did change some of the color coding ( OK to cringe Neil) to the engine as I was using "harsh environment bundled cable" for a harness (5 wires) for the power to the engine. I have an ammeter wired in at the "engine" panel I have below which eliminated a 30' charging run that's now less than 3'. Everything works better and I have more voltage available everywhere due to shortened runs, a good thing to consider when rewiring.
I figure the engine is part of the boat so why not include it with the boats wiring system instead of a separate one. All I really did was pick up my engine power from a source that was close and needed to be in the same area~~food for thought. It's my boat and I don't like the "Universal" wiring kits that were supplied due to the "plug".
I did make an engine wiring diagram for the boat files.
In the years since the boat was built many things were added and dropped etc, so things can get to be a mess. Take a good look at what you have and what you want, a bit of thought can really make things a lot simpler.

Dave Neptune

[seapadrik]

Thanks again guys.

To answer Neil's questions.

- Electric fuel pump
- Yes I would absolutely love a harness drawing if you are willing to provide one.

So based on your comments I probably won't fuse the run for the 55 amp.

As to my other questions. How many grounds do you guys have on your engine ? I have a green ground that connected from a brush strap on my shaft, is that shaft a common thing ? Also the bilge blower grounds at the engine. Black Battery cable grounds there.

Is it my understanding there should be only one ground on the engine and maybe migrate the grounds off of it ?

thanks

[ndutton]

Here you go. You'll have to rotate the pdf once it opens.

The lengths on the table reflect the harness approaching the engine from the rear (opposite the flywheel) on the alternator side and wrapping around the front terminating at the oil pressure sender. Wire colors and gauges are noted at the top left of the drawing. Due to its location and if its switch is in the instrument panel you may want to add a brown w/yellow stripe (or brown or yellow) wire from the instrument panel to the blower. Bringing the blower's black ground from a ground bus avoids tying it to the engine block (see next paragraph).

Best form on the grounds is to land the battery cable on the engine block and a single #6 cable to a ground bus bar rather than a bunch of grounds peppered all over the engine. The shaft strap you have is necessary if you have a flex coupler between the engine and shaft coupler. If not, get rid of it.

Please review the previously provided ABYC color code. Of particular concern is the existing use of green and white wires in regard to the battery.

[systemek]

Re-wiring........ a pre-requisite

Here to chime in! Patrick, you are in great hands with Neil. I was overwhelmed and definitely intimidated about a rewiring. I was more comfortable with mechanical issues and the wiring diagrams seemed confusing. In the end, I found the wiring project to be one of the most satisfying boat projects of all time. It was surprisingly less scary because of Neil, who also taught me some indispensable practices (heat shrinking etc). I just peaked at the before and after pics and it gave me a buzz......Your situation doesn't look as dire as mine, but I look forward to seeing the results!

[seapadrik]

Good Stuff. Thanks Neil for the diagram that is fantastic. Next is for me to actually understand it

So i have a few questions for Ezra or others, could you kindly post a picture of where the wiring harness meets the back side of the instrument panel ? I learn much better with pictures and want to see how those connections are made.

Neil, i see you have a #12 black ground going back to the instrument panel and forward to ? what does that attach to at each end please ? Also if i had yellow would that be the same ? it seems according to that color chart both can represent ground.

Question about these 3 in the diagram:
ignition purple #12
start white #12
hot red #12

Is it safe to say all 3 of those wires begin their run on the ignition switch ?
Also is the hot red #12 interchangeable with the yellow/red wire that I keep reading about on some of these sites ?

Although while perusing around my local shops like fishery supply and some marine electric supply stores it seems that yellow/red wire is hard to come by.

I will go shopping in the morning and try to do this thing over the weekend and have it done.

thanks

[ndutton]

It's my preference to bump up the ignition wire gauge when more equipment is running off the circuit than the ignition alone. In your case that means the electric fuel pump. In my case it's the electric fuel pump AND an electric coolant pump AND an alarm system with a delay relay AND a fuel pump indicator light AND a tachometer. Same strategy with the ground if there are additional items at the control panel such as gauge lights or alarm system.

You may have to make color adjustments based on availability, it's not uncommon but I recommend you make detailed notes for future reference. Wouldn't it be nice if your previous owner provided a diagram of the things he did?

If you're using a key switch, the white, red and purple wires in the harness connect to it on the S (start), B (battery) and I (ignition) terminals respectively. There are other wires connected to the I & maybe the B terminals depending on your panel wiring. I'd give you my instrument panel diagram but it's wicked complicated with a variety of accessories that I'm afraid would confuse matters unnecessarily. It's available if you want it, just say the word.

[systemek]

Another priceless trick taught to me by the guru, himself:

Wrap-on Wire Marker Books

http://www.mcmaster.com/#wire-labels/=najzyd

Just don't lose your code chart a real PITA (don't ask how I know)

Wish I had some pics of the back of my instrument panel, but I do not, and am not near the boat right now.........

[seapadrik]

Made some purchases.

http://www.flickr.com/photos/28554500@N08/9105064094/lightbox/

I got the # 6 GA and a bus bar plus Nigel Calders book.
I just rewired my entire 1910 house ( along with a certified electrician ) converting from entirely knob and tube setup with 100 amp panel to modern 200 amp service and all new wires. So I suppose its time to divert my attention to DC wiring.

So basically there will be only two ground wires on the engine. One from the battery setup and this one here going to a bus bar in engine compartment.

My assumption is that engine compartment best place for bus bar? at a minimum i can put the blower motor ground on it. And possibly that bonding strap if it turns out i keep it.

Thanks