2020 Alternator Issues

Hey Guys,
My 2020 SA has had the alternator replaced per the Indmar recall/TSB.
I had it at the dealer for the warranty transfer and the tech said he was only getting 12V from the alternator.
I've always seen it staying at 13-14V .

Yesterday on the water I noticed my batteries hovering around 11-12V. I bumped up the RPMs up to try and charge no dice, so I turned the key off and back on and boom right back to charging 13-14V. No issues the rest o the day.

Does anyone know the specific issue that the alternators of the 2019-2020 Raptors are having? I find it really odd that simple toggling the ignition would have any effect on the alternator.

I find it alarming that SC is still having alternator issues since 2019.


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I thought it was the wiring harness from a 3rd party. Might be multiple things going.

Twice I have had to switch the battery because I get a read on screen that says "low voltage, increase RPM to 1500" this is while pulling tubers.
I thought I had a bad battery but now I wonder if I'm having the same issue.
Before I call my dealer, how do I know whether is alt low voltage or battery?
Just FYI, I plug my batteries into the onboard charger every day when I get home.

Quote:

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Originally Posted by Isaguel

Twice I have had to switch the battery because I get a read on screen that says "low voltage, increase RPM to 1500" this is while pulling tubers.
I thought I had a bad battery but now I wonder if I'm having the same issue.
Before I call my dealer, how do I know whether is alt low voltage or battery?
Just FYI, I plug my batteries into the onboard charger every day when I get home.

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It's 95% an alternator issue if you're seeing low voltage while at tubing rpm.
You should always be 14+v at those rpm.

It could also be battery but unlikely on something this new. It would show up more when you're sitting listening to music than what on the go.

It’s interesting. The 2020 manual recommends running the boat in 1+2 battery setting, 2018 for example recommends only running in 1 or 2 and only using 1+2 mode in emergency low battery conditions.

My assumption is they changed how the batteries are wired.


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Quote:

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Originally Posted by larry_arizona

It’s interesting. The 2020 manual recommends running the boat in 1+2 battery setting, 2018 for example recommends only running in 1 or 2 and only using 1+2 mode in emergency low battery conditions.

My assumption is they changed how the batteries are wired.


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No change on wiring according to my tech, just 2 batteries is better able to deal with the large amp draws on the system these days. 6 ballast pumps + stereo + lighting + ecu + etc etc ends up with large draw that can pull down a single battery quickly.
I run in both and switch to a single if I'm sitting with the engine off with the stereo on for more than a couple house so I have a backup to crank from if the stereo kills the battery.

So this appears to have happened to me today. For reference, we have always had the dual battery switch on 1+2 (combo) when running the boat. Always. Session starts out normal, after we fill and start surfing we get the, "low voltage, increase RPM to 1500". We were obviously at much higher (i.e. 4800 rpm) for surfing. We do one more pull to see if it changes, it does not, so we start deballast and head back to dock. We're at far end of lake from our dock. We go from 11V down to 10V, 9V during the deballast. We're losing 1V every 3min or so I'd guess. I get worried about the engine cutting out so I turn off ballast and we continue to head back to dock with about 30% ballast still left in. We run for a minute with no other electrical draw on the system and we gain back +1V. Eventually we get back to dock and are able to finish deballast. Voltage is still showing low ~9-10V after the deballast. (Ran in neutral at 2000 rpm to finish deballast.)

So after all that, I start reading forum, see this thread, call dealer, talk to local non-dealer marina mechanic, and take batteries out for testing at local auto shop. Dealer says that other moomba 2021's have had some alternator issues this spring/summer but wants us to confirm that it isn't water in the bilge sloshing up on the serpentine belt and shorting/stopping the alternator from working??? Tells us to air out the engine compartment and alternator for a few hours and try again the next day...see if problem persists. We are 3.5 hours from dealer and just starting a 10 day stint at the lake so the timing here is real bad.

The testing from the auto shop on the two batteries is interesting. They are both 850 CCA batteries. One of the batteries checks out at 12.5V and 810/850 CCA. The other battery comes up at 440/850 CCA. Both batteries pass the structural integrity??? part of the test. The auto mechanics saying the one battery is just low and needs to be charged up. This kinda took me by surprise because I thought that when we set it to 1+2 that we're essentially paralleling the batteries, are we not? Why would one battery be so low compared to the other if I always run 1+2? Is there some sort of controller circuit happening in the background that would isolate one battery over the other during starting or ballasting? I thought I understood the dual battery switch and now I'm not sure.

Anyone have any ideas on this?

The plan for tomorrow is to finish charging the one battery overnight, then do everything the same as today but run a meter across both sets of battery terminals and see whether I'm getting +13-14V on the battery terminals at 4000 rpm. If we are not, then I think I can safely say it is alternator, yes?

You are not supposed to run in 1+2.

Recharge fully and use only 1 or 2.

If you run in 1+2, the alternator can’t keep both batteries charged.

Check you owners manual. The 2020’s were wired differently and recommended using 1&2, but 2021 changed back to how it was before.

Perhaps your dealer used the 2019 battery hookup method.

https://uploads.tapatalk-cdn.com/202...0bc4e55d6e.jpg


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Hrm. When I talked to dealer he asked the question to confirm that I was running 1+2. He never mentioned or insinuated that I should've been running 1 or 2. Thanks for the heads up, I will take a look at the manual.

We have put 75 hrs on our new to us 2019 since may running on both batteries with no issues. The alternator should have no issues charging both batteries at once.

That's the bit I don't get, if I've been running dual mode since the start, why would there be such a discrepancy between the two batteries?

Quote:

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Originally Posted by Hayden

That's the bit I don't get, if I've been running dual mode since the start, why would there be such a discrepancy between the two batteries?

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Sometimes one just get week and will drag the other one down. How old are they

Never mind I see your boat is a 2021. I would check for loose connections at the alternator itself. I had charging issues on my last boat once and it was a loose power wire on the alternator

I checked the connections on alternator. All looked solid. I made a quick video showing us testing the battery voltage (on battery terminals) and alternator voltage (on alternator terminals) under 3000 rpm load.

Is there anything else I can do to prove/disprove that this is an alternator failure?

https://photos.app.goo.gl/gctPey6cZtCL1xoe9

Quote:

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Originally Posted by Hayden

I checked the connections on alternator. All looked solid. I made a quick video showing us testing the battery voltage (on battery terminals) and alternator voltage (on alternator terminals) under 3000 rpm load.

Is there anything else I can do to prove/disprove that this is an alternator failure?

https://photos.app.goo.gl/gctPey6cZtCL1xoe9

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Voltage is normally 14-14.4 on my cars I work on. 2021 mojo showed 14 on the dash with 1&2 batteries on.


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Quote:

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Originally Posted by boating406

Voltage is normally 14-14.4 on my cars I work on. 2021 mojo showed 14 on the dash with 1&2 batteries on.


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Is that under load (ie. 3000 rpm) or idle or engine off?

Voltage should be between 13.7-14.4 vDC when charging from alternator, and that charge is “bulk” charge.

Here-in lies the problem of using one battery during float time. Lead acid and AGM batteries once depleted past 50% capacity (critical depth of charge) will drop 20-30% from total capacity. So, if you drop a new LA battery below 50%, the new capacity is going to be 80% or less. This won’t affect CCA until you reach 50% of original capacity as that is related to charge cycles, depth of charge, and charge rate, but dissipation rate will decrease. AGM batteries can handle more cycles and decay is on the lower end of scale.

So now you have a battery that only has 80% capacity, and you drop it below 40-50% of its original capacity, and now you have a battery that has only 40% capacity. This cycle continues and it depletes CCA, and if starting in parallel, the discharge rate in attempt to equalize both batteries and crank the engine can pull the second battery below 50% under high dissipation load which accelerates second battery decay.

LA and AGM batteries are best charged slowly with absorptive charging, as rapid charging and bulk charging can overheat the cells slowing electrolysis. Multiple rapid charges at depth weaken the transfer of electrons between the solution and electrode plates and mesh because heat created during the reaction causes solute to gas, being unavailable to receive electrons.

The process of relying on manual methods to balance battery drain are antiquated and would easily be solved with adaptive shunts and load managers that keep dissipation at above 60% capacity.

The dual battery switch is a tradition embedded in any leisure boater, but is a relic of a time when tech couldn’t adapt. If you look in any emergency vehicle built after 2006 that utilizes multiple battery banks and has extreme electrical loads, load managers will shut down systems in order of least needed to highest priority and maintain a starting voltage of >12.7vDC. The battery banks are paralleled to maintain constant states of dissipation and charge, so the batteries fall in the same replacement cycle and don’t have to take care of each other.

Until boats are fitted with load managers to reduce parasitic and non-charge state drain, and because we are human and fallible, floating on one battery versus both, and running on both batteries offers the least probability of an incapacitating event.

We ran our boat on both batteries, and floated on one, being mindful to switch to Bat1 on odd days, and Bat2 on even days. But even this system has a failure point. Maybe weather and work have only allowed us to boat on odd days. Bat1 is going to get battered and it’s life cycle is only going to shorten.

I argue that modern leisure boats need solar battery chargers to maintain battery systems and extend battery life. A 30amp panel and 40amp PCM charge controller would cost less than $200 and could be incorporated into the unusable dash space. This would provide enough absorptive charge to reduce most parasitic and entertainment voltage uses prolonging the dissipation time, keeping the dual battery switch as another safety-system factor.


Currently boatless

Quote:

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Originally Posted by Hayden

Is that under load (ie. 3000 rpm) or idle or engine off?

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Idle or higher rpm. If you have a massive stereo and running all 6 pumps you could see the voltage drop.

13.7 - 14.4 like the above poster mentioned.


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I don't have much to add because when it comes to electrical stuff i am an idiot. Is it possible that you just have a battery that is going bad? I've had a battery crap out in just a few years and others that have lasted 10 yrs in my car.

As far as using 1 battery or both when running the boat our dealer said to always use 1+2 so that you keep both charged up. I've seen at least one other video from another dealer doing a walk through on a new Moomba on youtube and they also said to use 1 + 2 as well.

Step A: Test the battery with lowest charge first. Ensure battery switch is off. This will be your baseline voltage. If less than 11.7 vDC, charge battery for several hours with a smart charger. Retest voltage.

Step B: Next turn the battery switch to the lowest battery. Measure and record voltage. This will ID parasitic drain voltage.

Step C: Turn on ignition and let systems fully boot up, approx. 30 sec. ensure audio, lights, pump systems, blower, are all turned off. Record voltage.

Step D: Turn ignition off and select power off on control system. Wait 10 sec, then turn ignition back on and let system boot up, blower run. Audio, lights, pumps should be off. This is your pre-start voltage. Measure and record. If low battery is below 11.7 vDC, battery should be replaced.

Step E: start engine and record voltage input. At idle, voltage should be 13.7-14.4vDC. If not, check alternator connections to battery switch/bus bar. If no issue, and voltage is 12.9 vDC or less, have voltage regulator on alternator tested, and assess for engine / fuel system shorts and bad connections, then move on to next step. Goal is to have idle voltage between 13.7-14.4.

Step F: at idle, engage pumps for 5 min. Record voltage. If voltage at battery drops below 11.7 vDC and remains after pumps are shut off and engine at idle, there is a short in the pump system. If voltage returns to 12.9 or better, system is ok, but not performing optimally. Isolate and assess any parasitic drains. Clean/replace/tighten connections.

Step G: at idle, run audio system for 10 minutes at volume you would usually float with. If voltage drops below 11.7 vDC and remains after audio is shut off and engine at idle, there is a short in the audio system. If voltage returns to 12.9 or better, system is ok, but not performing optimally. Isolate and assess any parasitic drains. Clean/replace/tighten connections.

Repeat with Bat2.

Idle voltage 12.9 or less suggests poorly performing alternator, voltage regulator, or circuits. Cycle all breakers and ensure no partial disconnects that may be causing resistance. Check belt condition and tension, pulley tightness, etc.

Unequal idle voltage between battery banks may indicate failure in charge circuit or battery switch / bus bar. Repeat test with Bat1 or Bat2 physically disconnected. If voltage returns to 13.7-14.4 replace disconnected battery as a cell may have collapsed.

If none of this results in diagnosis or solution, the gremlins may be deep. Seek professional help and good alcohol to absolve your frustrations.


Currently boatless

What was the voltage at the alternator?

Quote:

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Originally Posted by gedakbx

What was the voltage at the alternator?

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12.5V


RE: 2in2out's posts, I have lots to work on there. Did you get that from a website? If yes, have a link?

I could have a less efficient battery now according to those points. It tested ok at mechanic shop. Still not sure how there could be such a big descrepancy between the two if I've always been running them shared.

Appreciate the suggestions. Thanks.

Quote:

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Originally Posted by Hayden

12.5V


RE: 2in2out's posts, I have lots to work on there. Did you get that from a website? If yes, have a link?

I could have a less efficient battery now according to those points. It tested ok at mechanic shop. Still not sure how there could be such a big descrepancy between the two if I've always been running them shared.

Appreciate the suggestions. Thanks.

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12.5v at the alternator indicates a malfunctioning alternator or regulator. 12.9v is a minimum input voltage to keep a battery topped off and provide systems voltage for critical engine components. For accessories, more voltage needs to be supplied by the alternator, hence the 13.7-14.4 range. A weak battery can put a lot of load on the alternator causing premature failure.

Given the materials and worker shortages I can see vendors cutting corners and a lot of system components failing. This should be a warranty issue and I hope it can be resolved quickly.

Batteries can fail for multiple reasons. Discharge rates, temperature, and manufacturing issues. If you shock a battery hard enough you can collapse a cell, decreasing output and battery life. This can happen when it’s being loaded on a pallet for shipping, etc. Lead acid batteries are weak, cheap, and prone to failure. AGM batteries are more expensive, have better service time, but require a lot of care in the charge/discharge cycles.

As far as a website for this info, I did a lot of research on RV solar systems and went down a van conversion rabbit hole. I learned a lot about integration of different battery systems into vehicular charging systems from electrical engineer blogs. I left lithium batteries out of the discussion as they aren’t practical cost wise, or system wise, but they would handle better as “house” batteries.


Currently boatless

So now I'm thinking the one battery may be compromised because I ran it down to 9V trying to get back to the dock and deballast.

Quote:

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Originally Posted by Hayden

So now I'm thinking the one battery may be compromised because I ran it down to 9V trying to get back to the dock and deballast.

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I would still have the alternator bench tested, but replacing that battery is probably a wise choice.


Currently boatless

I sent my testing videos to my dealer and then took the boat in to have it checked out. It was 100% a faulty alternator and dealer was saying that with the (Indmar) boats they've sold in the last year, 1 in 6 came back in for faulty alternator this spring/summer. It's running 14.7V when above 2000 rpm now.

My 20 sl450 did this last season several times. Usually when we had all the lights on at night. My batteries were never low though. Dealer looked at it last fall and couldn’t find any issues. I’ve had a several times this summer where I get the voltage below 11, maintain rpms above 1500 warning still. At this point I’ve just disregarded it as a glitch in the system. You would think there would be some kind of problem but dealer couldn’t find anything and it hasn’t caused any issues.

Quote:

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Originally Posted by Hayden

I sent my testing videos to my dealer and then took the boat in to have it checked out. It was 100% a faulty alternator and dealer was saying that with the (Indmar) boats they've sold in the last year, 1 in 6 came back in for faulty alternator this spring/summer. It's running 14.7V when above 2000 rpm now.

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That's a good find!

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