New Alternator Question

[Don S]

Re: New Alternator Question

-Red w/purple stripe ton "S"-Sense
-Purple to EXC-Exciter
-Orange to B+

That is correct.
The purple/yellow wire that you don't have is for the electric choke.

 

[Levinz11]

Re: New Alternator Question

-Red w/purple stripe ton "S"-Sense
-Purple to EXC-Exciter
-Orange to B+

I did this....now I have 15.95 v at the battery while idling.

Also; when I disconnected the red wire in the pic above I had no juice to anything. This sucks. I guess the PO did a hack job on the harness. Anybody have any ideas? I'd appreciate them.

 

[Levinz11]

Re: New Alternator Question

My Cobra factory manual shows the two wires joining each other in the harness. I also have a Volvo "LK" manual that shows the EXC and Sense wire joined on the alternator and one wire going back to the ignition switch.

There is definitely no reason to not have the sense line on the output as shown in DonS's picture. In fact, that is a way better place to sense the voltage. If you wanted to be more precise you would have it on the battery to account for voltage drops in the orange wire.

Only the EXC wire really needs to be switched.

Can you expound on this Bruce. If you were me....where would you attach my 3 harness wires and random red wire.

 

[Levinz11]

Re: New Alternator Question

For reference here is a shot of how I have it hooked up right now.

 

[Don S]

Re: New Alternator Question

Does your orange wire go to the starter solenoid on the same terminal as the battery cable?
If So, Disconnect your red purple wire from the S terminal on the alternator, and tape it off so it won't short against anything.
Then make a jumper wire (14ga or larger) that goes from the S terminal to the B+ terminal on your alternator.

Start it up and see what you get. If still too high, you may have a defective regulator in the alternator.

(EDIT Typing while you were posting the above.)

 

[Don S]

Re: New Alternator Question

Is this how your wiring is setup? Including the orange wire going to the solenoid and then through a fuse to the starter ? If so, I wonder how any of the OMC 's every charged, or even started and ran.

 

[Levinz11]

Re: New Alternator Question

Does your orange wire go to the starter solenoid on the same terminal as the battery cable?
If So, Disconnect your red purple wire from the S terminal on the alternator, and tape it off so it won't short against anything.
Then make a jumper wire (14ga or larger) that goes from the S terminal to the B+ terminal on your alternator.

Start it up and see what you get. If still too high, you may have a defective regulator in the alternator.

(EDIT Typing while you were posting the above.)

^^^^Did This^^^^

Damn, you're good Don!

Good news: 14.62v at the battery while running
Bad news: Dash gauge showing 10-11. Say screw it and go boating??

 

[Levinz11]

Re: New Alternator Question

Is this how your wiring is setup? Including the orange wire going to the solenoid and then through a fuse to the starter ? If so, I wonder how any of the OMC 's every charged, or even started and ran.

View attachment 152532

It may have been wired like that at some time but it looks like several people have made mods to the harness. Lots of homebrew tape and wiring going on. They did a pretty good job but a lot of it doesn't look like "factory" work. I didn't see a fuse between solenoid and starter because I can barely fit in there to see what's going on. I've only had the boat about 2 months and it is my first. I'm learning a LOT here.

 

[Don S]

Re: New Alternator Question

Get your DVM and with the engine running and 14+ V showing at the alternator or battery, check the + and - terminals on your dash volt meter. If your wires are screwed up, you may only be getting 10 -11 volts to your ignition.

 

[Levinz11]

Re: New Alternator Question

Get your DVM and with the engine running and 14+ V showing at the alternator or battery, check the + and - terminals on your dash volt meter. If your wires are screwed up, you may only be getting 10 -11 volts to your ignition.

11.5-12v at Dash V Meter (Meter reading the same)
11.5-12v at Ignition (key)

Is this bad news? What should I check next?

 

[Don S]

Re: New Alternator Question

Do you get your 14.5 volts at the battery or at the alternator? Did you check your orange wire and see where it goes????????????? That is a biggie, that 14 ga. red wire you have going to the battery is not something I would head to the water with. It may be a big part of your problems.

 

[Levinz11]

Re: New Alternator Question

Do you get your 14.5 volts at the battery or at the alternator? Did you check your orange wire and see where it goes????????????? That is a biggie, that 14 ga. red wire you have going to the battery is not something I would head to the water with. It may be a big part of your problems.

Yes 14.6 v at battery while running.

To find out where the orange wire goes is going to take some time and it's getting dark. It looks like I will have to remove the whole cluster of wires from the solenoid to determine if one of them is the orange one. They are dirty and have been taped up. Not to mention the space back there is minimal. Tomorrow I can really see where that orange wire goes.

Everything was fine before the alternator went. Why would someone put that 10 ga. red wire there in the first place? Is it a safety issue?

 

[Don S]

Re: New Alternator Question

Everything was fine before the alternator went. Why would someone put that 10 ga. red wire there in the first place? Is it a safety issue?

Maybe the fuse that goes from the solenoid to the starter is blown, Wouldn't surprise me, why would OMC install a 50A fuse in a circuit with a 55 to 65 amp output from the alternator?

And why would they have the wire going to the coil for power go through the alternators regulator before it gets to the coil.
Either the wiring schematic is screwed up or that is actually the way it's wires. But it looks like trouble to me.
Or maybe OMC uses the regulator in the alternator to cut the voltage down to the coil so it doesn't burn up the points. Hard to say. No wonder they went out of business.