Voltage a bit high

[JPass]

So I had the issue with slightly burnt wires going into the regulator/rectifier. I replaced them with new connectors.

Prior to swapping them out I was getting about 14.8v to the battery and also to the 12V plug on the dash. I used a small USB charger that has a voltage readout in the dash to monitor voltage.

After replacing the Deutsch connectors, I'm now getting 15.1v to both the battery and the dash plug. This is just a tad over spec. I'm not getting any high voltage alarms and the wires leading into the rectifier/regulator do not feel hot.

Should I be concerned and possibly replace the rectifiers or should I just keep an eye on it?

 

[ski-d00]

Have you verified voltage with a good multimeter? Not sure I'd trust one those cheap readouts.

I would swap out the rectifier with a used OEM for like $20 if the voltage is indeed high.

 

[JPass]

Have you verified voltage with a good multimeter? Not sure I'd trust one those cheap readouts.

I would swap out the rectifier with a used OEM for like $20 if the voltage is indeed high.

I did confirm with a handheld VM as well. Being that I have twin motors, should I swap them both?

Quick search shows a few used in the $50 -$60 range. Plenty of off brand new for same price (not the way I believe I should go). New OEMs for $160.

Not seeing any used OEM for $20.

 

[ski-d00]

I would swap one and see if it changes. If not, swap out the other motor with the new one and see if that changes anything.

 

[JPass]

I would swap one and see if it changes. If not, swap out the other motor with the new one and see if that changes anything.

Good idea.

Am I correct in my understanding that the non-OEM rectifiers are not worth buying?

 

[ski-d00]

My opinion is that they are junk. I've seen a lot of them and some work well but others don't work out of the box or last 1 hour. OEM just more reliable.

 

[JPass]

My opinion is that they are junk. I've seen a lot of them and some work well but others don't work out of the box or last 1 hour. OEM just more reliable.

That's kinda what I've seen.

OEM it is.

Thanks for the help.

 

[JPass]

So I went out today with a brand new OEM rectifier ready to swap out. Ran the boat for a bit and monitored the voltage. Never got past 14.8v.

Went to the sandbar for a few hours and turned off the main batt switch as we listened to music over the BT speaker.

Left the sandbar and went for a quick cruise, voltage was now back to 15-15.1v

I shut down each motor and ran each by itself to roughly 6k rpm. When running each motor by itself, each was reading about 13.8v. When I ran them together, I was back to 15v.

Why would they run fine alone, but then high together? Should I just swap out a regulator and see what's up?

 

[Premix]

Well, this is interesting. I’ve been thinking of proactively replacing those Deutsch connectors with bullet connectors.

 

[Mister Magoo]

Remember Ohm's law: volts=resistance x amperage. Could be resistance in a connector but sounds like a diode in the rectifier.

 

[JPass]

Remember Ohm's law: volts=resistance x amperage. Could be resistance in a connector but sounds like a diode in the rectifier.

But wouldn't I see a spike in voltage being delivered when I isolate each motor? Boat has two rectifiers, one per motor.

 

[Mister Magoo]

There has to be a commonalty between the two systems, like the battery charging circuit. Now I'm not looking at the wiring diagram but I assume that either system can charge the system which would mean there is a switch, a transistor/diode switch. Find that component and look for high resistance in a connector/wire. I think the 15.1 volts is the spike and if that voltage is found at the battery with either engine running the problem is downstream of where the two charging circuits come together.

 

[Mister Magoo]

I'm sorry I misread the prior post: Normal voltage with either engine running alone. Look between the battery and the component where the two circuits combine.

 

[Mister Magoo]

Just looked at the wiring diagram 2012 2 engine challenger. Both charging systems go to fuse block 2 fuse A on the A1 side then go to the starter solenoid and from there to battery switch. Have to think about why 15.1 together and not when one alone, which I think eliminates the regulators/recs.

 

[JPass]

I'm sorry I misread the prior post: Normal voltage with either engine running alone. Look between the battery and the component where the two circuits combine.

I'll check for a combiner of sorts. Looks like I'm just a hair over the max output of 15v. I have a buddy with a BUDS. I may have to hook it up and see what's really going on. I'm not getting any high voltage codes or anything yet.

 

[Mister Magoo]

Just for shits and giggles, after you start both engines disconnect the negative side of the battery and do a voltage reading between the negative cable and the positive side. BTW, the wiring diagram does not show any kind of switch/combiner, its a fairly simple system. I would suspect both regulators/recs have diodes internal to prevent any kind of cross circuit feedback.

 

[JPass]

Just for shits and giggles, after you start both engines disconnect the negative side of the battery and do a voltage reading between the negative cable and the positive side. BTW, the wiring diagram does not show any kind of switch/combiner, its a fairly simple system. I would suspect both regulators/recs have diodes internal to prevent any kind of cross circuit feedback.

Yeah no combiner that I can see. So start the motors, while running, disconnect negative terminal from batt. Check voltage between negative cable and positive batt terminal?

I believe we'll be testing the grounding cable with this? I won't be using boat until at least the weekend, so it'll be a few days before I can test it again.

Appreciate the help.

 

[Premix]

it'll be a few days before I can test it again.

How did you make out?

 

[JPass]

How did you make out?

I never swapped out the regulator being that I was literally just on high side of spec. Each time I head out, I check the voltage. It seems to be in range for the vast majority of the day with the occasional spike to 15.1V

Wires going to the regulator are not hot, so for now I'm just going to continue to monitor it.