Merc 470 alternator conversion help

aarons 470

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Hi all. I installed my alternator conversion bracket and alternator. Have some questions about the electrical routes.

2 yellow wires off stator wheel area are obsolete now.
The square block by stator that has small studs for wire hookups (not sure what it is) it has coolant hoses hooked to it also.

This part has 2 red wires going to it. Striped and solid. Solid comes from started solenoid. And striped comes from wire bundle, not sure source.

There's also a small black wire that comes from the square part.

Where do I reconnect these 3 wires?

Any other tips would be appreciated. I need to remount the radiator overflow somewhere anyone have a picture of a good method?
 
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achris

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That square box is the regulator.

The black wire is the ground, the red is the main feed back to the battery, hook this to your new alternator output. The smaller wire is red/purple the 'sense' wire for the old regulator. If you have a 'one wire' alternator, tape the red/purple back. Also be aware that the red/purple is live whenever the battery switch is on.

HTH,

Chris.........
 

aarons 470

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Ok thanks. I'm still confused though. And regulator brings up more questions.

So black is ground, I think I'm good on that one, lol.

My regulator will not be used at all correct?


I don't have a smaller red/purple wire so I want t make sure I have it correct.

I found a Mercruiser diagram online. Says to put the Red white on the "output" post on the regulator. So does this mean my Red and white goes to my alternator?

I'm confused with the solid red wire now. If the above is correct.

One solid red short wire goes from the regulator to the starter solenoid, Connects at the same spot as a larger positive battery cable on the solenoid (I think goes to starter?). So do I need to lengthen this wire and run it to the new alternator from the solenoid?

I have a 1 wire alternator.


I appreciate the help, thanks again
 
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stonyloam

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You may remove and discard ALL of the wires from the regulator, it's only purpose now is to hold the water tube. Tape off and fold the yellow wires out of the way. If you ever need to remove the rotor from the crankshaft you may remove the stator entirely.
 

aarons 470

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Ok glad to hear I don't have to use the regulator other than for the tube. ill wrap up the yellows.

So on a single wire alternator do you just run a wire from alternator directly to the battery?

Or do i use the red wire with white stripe to go to alternator? Online states the red/white goes To output on the regulator so it must need to go to alternator now?

There was a red wire going from regulator to solenoid as well. Should I run this wire from solenoid to alternator?
 

aarons 470

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470 Alternator conversion wiring help, Mercruiser

Hi all. I'm trying to figure out now to wire my single wire alternator to my system. Read older threads but I couldn't really find a definitive answer. Its an older engine, I've removed wires from old regulator.

I'm pretty sure I need to get rid of the short red wire jumper that went from solenoid to regulator.

And I am left with a red and white wire. And from what I've read goes to the ammeter and then back to circuit breaker then to solenoid? This wire was originally hooked to the power output on the regulator.

So it seems like you would just hook this red and white to the new alternator and be done with it? but I read this can fry the entire system because the new alternator puts out more power than the old system.

So my questions begin if I am right so far.....

Do I just tape this red/white wire off, and not use it for anything. I am worried this may kill an important circuit?

If this wire is obsolete, What should I hook my alternator power wire to? I am going to install a switch cutoff for two battery system (if this makes hookup location different)

I appreciate the help
 

achris

More fish than mountain goat
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Ok, so I can look at the specific wiring diagram, please can we have your engine serial number (or at least a year)... I will also need to know exactly what wires you have and where they currently go. I also need a picture of your instrument panel (or let me know if you have an ammeter)...

In that era (1974 to 1986) there were MANY different options and configurations of engine wiring and instrument panel, and we need to exactly which one you have....

And what is the maximum current, in amps, the new alternator will produce?
 
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stonyloam

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OK, IF you have a one wire alternator. Then you have a ground (it may be grounded through the case) and an output wires. On the 470, once you have removed all of the regulator wires, you should just be able to run a red (I think 8 gauge is recommended) wire to the battery +. Usually that connection is made using a ring type connector going to the large post of the starter ( where the red battery cable connects).
 
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aarons 470

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Thanks guys, Stony, I hope that's the case, def the easiest for me to do.
I've read so many opinions about the existing wiring just want to be sure. Then when I go to start it up I'll know this part is good to go if I have to troubleshoot. Here is the info on my engine.

Its a 1977, in a Cobia boat.

Serial number 4772759

It does have an AMP meter. I am trying to get pictures up not the easiest to do on this forum. Tried with phone and computer. Says my pictures are to big to upload.

I'll explain what I have incase pics don't work.

Amp meter has 2 thicker orange wires (or oxidized red) pretty sure there orange. on opposite terminals. looks like They go into loom to the rear.
And a single red wire goes to ignition. I replaced this wire last year, it may have been a different color originally.

I don't remember configuration of wiring on my regulator. I had it written on blue tape, it rubbed off.

On regulator done with the yellows, and small ground wire.

I'm left with a red/white wire that goes into loom.
And a short red wire going to solenoid power side. (I replaced this so may not have been red before)

I don't know anything about the alternator. Its a basic one wire, came with my conversion kit.
says "SAE J1171" on it its a marine alternator.

Thanks guys, appreciate the help
 
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stonyloam

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Well the AMP meter complicates it a bit. That is usually wired in series with the charging circuit. With the amp meter I think you would go from the alternator output to the + terminal of the meter, and from the - terminal to the + of the battery (starter post). More modern boats have voltmeters (wired in parallel) to monitor battery voltage.
 

achris

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Well the AMP meter complicates it a bit. That is usually wired in series with the charging circuit. With the amp meter I think you would go from the alternator output to the + terminal of the meter, and from the - terminal to the + of the battery (starter post). More modern boats have voltmeters (wired in parallel) to monitor battery voltage.

correct on all counts. Which is why I was asking for the information on everything in the boat. When I can get back on the computer I'll look into and get the right information on how to hook the new alternator up (currently on a phone :facepalm:)....
 

achris

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ok, at the computer. Your current setup (before the new alternator) was to have the output of the old alternator, via a regulator, go through the ammeter, as Terry mentioned. As you have an ammeter in circuit you can't just ignore it. All the feed for the instrument cluster and the keyswitch, which then means ignition and starting, feeds off that meter. The other side of the meter is then fed back to the engine harness and to the battery, to charge it....

You have a couple of options. For all options, remove and discard the red wire from the old regulator to the starter solenoid.

As the output of the original alternator setup was only 39A and the new one, I suspect, will be at least 60A you can't just hook straight up to the existing wires.

Option 1. If you want to keep everything as 'normal' as it is, and the 2 orange wires are big enough (8mm minimum). You will need to upgrade the circuit breaker to the output current of the new alternator, or it will trip whenever the alternator output goes above 40A. Move the orange wire that was on the old reg to the output of the new alternator.

If the orange wires aren't big enough, you need to run a new pair of wires, one red, one red/white, using 6 or 8mm wire. At the ammeter end, remove and tape back the orange wires. Connect the red/white to the terminal the red ignition keyswitch is on and the large new red to the other...At the engine end, connect the new red/white to the output of the new alternator and the new red to a new circuit breaker (the side that goes to the instrument panel, not the side that goes to the starter solenoid). Basically, just putting 2 new wires in place of the orange wires that aren't big enough.

The 2 yellow wires from the old stator can be either cut back as close to the stator as you can get or just sealed up and tied back. This gives you the existing system with the new alternator and the upgraded wires.

Option 2. Leave the ammeter in the panel and just have it not reading. Add big red wire (6mm or bigger) from new alternator output to the starter solenoid (where the old red was). Tape back the red/white that was on the old reg. At the instrument panel, on the back of the ammeter, remove and tape back the orange that was on the same terminal as the red for the ignition keyswitch, move the other orange wire on the back of the ammeter to the same terminal as the red that goes to the keyswitch (the one you left on there)... This will also not require upgrading the circuit breaker.

Option 3. (my preferred option :D) Same as option 2, but remove the ammeter and put a voltmeter in its place.To do that, just do all of option 2, then pull the ammeter out and put a voltmeter in it's place. The terminals of the voltmeter, '-' to any black, the '+' will have the red and the orange....

Option 4. (my least favourite). Leave the ammeter in the panel and just have it reading current drawn (I suspect this is what most people would do, but I don't like it). Add big red wire (6mm or bigger) from new alternator output and starter solenoid (where the old red was). Tape back the red/white that was on the old reg. At the instrument panel, on the back of the ammeter, remove and tape back the orange that was on the same terminal as the red for the ignition keyswitch... This will also not require upgrading the circuit breaker.

HTH,

Chris..........
(I think I got it all :D)
 
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stonyloam

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Wow Chris! That was pretty impressive, you might not be the dumbest guy on the site after all. LOL!

P.S. I like the idea of going with a voltmeter.
 
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achris

More fish than mountain goat
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Wow Chris! That was pretty impressive, you might not be the dumbest guy on the site after all. LOL!

P.S. I like the idea of going with a voltmeter.

:rofl:

Ah, man, I remember that... Who was it? He got himself banned if I remember correctly.

Have another read Terry, I've been editing it quite a bit.

Cheers,

Chris....
 

aarons 470

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Well...... I'm speechless.
Thanks Chris!!
I will take option 3 please, with a side of volt meter. Good instructions I can handle it now.

One thing, probably doesn't matter as im doing option 3?
On option 1 you mention an orange wire that went to regulator. I don't think it had one. Maybe someone changed it at some point. Just 2 yellows, ground, red/white, short red to solenoid.

ill get a voltmeter ordered, some wire and new connectors and keep you posted on what happens or if I confuse myself.

Thanks guys
 

aarons 470

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Hi guys. Wiring my stuff up. First question- on the solenoid I cant fit all the wires on the post without removing the larger inner nut that has the built in washer (shield) that covers the plastic. Is it okay to remove this and screw on a smaller nut in its place to gain room? This is how I have it now and my connectors all fit.
 

aarons 470

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Looks like I was in the process of replacing my ignition switch when I started this project. I now have a 3 pole switch. I want to double check to see if I'm wired up right. I had it marked with tape but the pen seems to be the disappearing type. And I think my old switch had 4 terminals.


1- Off of the Solenoid terminal I have a wire that goes into a small flexible sheath that connects to the throttle arm. The wire has a soft insulation instead of the regular colored plastic. So I'm not sure of the color.

2- Off of the Battery terminal I have a wire to the new voltmeter positive side.

3- Ignition terminal has 2 wires. One runs to positive terminals of gauges (except voltmeter)
And a pink or peach colored wire that goes into larger bundle to the rear.

I have a switch panel that has my accessories that will be used when boat is off. Running lights, anchor lights, radio, cigarette lighter, blower, bilge.
Do I want this to have direct power from my second battery (accessory battery, I am installing 2 batteries with switch) or should I run it to the ignition switch so I have to have switch turned to use. And what terminal would you connect to for accessory, when you turn it to the left?

Sorry about all the questions. I just don't want to fry what I'm trying to fix.:eek:

Thanks
 

achris

More fish than mountain goat
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Messages
27,468
Looks like I was in the process of replacing my ignition switch when I started this project. I now have a 3 pole switch. I want to double check to see if I'm wired up right. I had it marked with tape but the pen seems to be the disappearing type. And I think my old switch had 4 terminals.


1- Off of the Solenoid terminal I have a wire that goes into a small flexible sheath that connects to the throttle arm. The wire has a soft insulation instead of the regular colored plastic. So I'm not sure of the color.

Correct. This is the wire that pulls the starter solenoid. It runs into the throttle control for the neutral safety switch.

2- Off of the Battery terminal I have a wire to the new voltmeter positive side.

No, the only wire on this terminal should be the wire that runs from the engine harness through a 20A fuse. The one that has power on it as soon as you turn on your battery switch. The positive of the voltmeter should be on the same terminal as the positive of the other gauges.

3- Ignition terminal has 2 wires. One runs to positive terminals of gauges (except voltmeter)
And a pink or peach colored wire that goes into larger bundle to the rear.

I have a switch panel that has my accessories that will be used when boat is off. Running lights, anchor lights, radio, cigarette lighter, blower, bilge.
Do I want this to have direct power from my second battery (accessory battery, I am installing 2 batteries with switch) or should I run it to the ignition switch so I have to have switch turned to use. And what terminal would you connect to for accessory, when you turn it to the left?

I have a philosophy of leaving engine wiring and boat wiring (accessories) completely separate. I put a couple of coloured terminal blocks in (one red, one black, see picture below), run a heavy (6mm) pair of cables directly from the back of the battery switch to them and run the accessories from those. Leave the engine wiring for engine stuff only. The only things I run from the engine harness/gauges is a fuel gauge and an hour meter.

Sorry about all the questions. I just don't want to fry what I'm trying to fix.:eek:

Thanks

Acc terminal blocks.jpg
 

aarons 470

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Thanks chris. Would you happen to know the color of the wire that's supposed to go to batt term on ignition switch?

I'm not seeing a 20 amp fuse in any of my wiring. Maybe someone cut it off.

You said it comes from batt switch, is that all it is straight run from power with fuse inline?
 
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