2020 df20at alternator question.

[Zabbaskeema]

Hi all, can I disable or remove the alternator? I don't need it to charge anything at all and.

In fact the starter is connected to our house bank and I don't want the alternators to interfere with how we are charging the bank.

Thanks!

Patrick.

[Moonlighter]

So, if you do that, what is going to supply the engines ecu with power to run the engine and all the associated sensors??

Very odd question…..

Perhaps you first might more fully explain your boats current electrical arrangements eg number of batteries what their respective roles are and how they are connected and charged.

And then, what your concerns are with the current arrangements.

Then there can be some more informed comments/suggestions from members.

[Zabbaskeema]

Sure!
I have 2 lithium banks, one 12v and one 48v.
I am using another 240ah lithium battery for the windlass and starter battery for the Yanmar Generator -> the big 12v bank takes care of the 240 ah "windlass lithium battery".
I want to use the same lithium "windlass" battery to electric start these Suzukis - and supply whatever 12v power they need for ecu and whatever else.
I don't need their alternators to contribute charging a battery it simply cannot charge properly.
I should have been more precise.

So if there is a field disconnect on them it solves my problem. If not then I could simply remove the alternator altogether?

Clearer?

Thanks

[Moonlighter]

Yes that is useful clarification.

Its way above my pay grade to offer opinion on de-activation of the alternator and using an alternative source of starting and operating power as you propose, so I will leave that to others.

[Zabbaskeema]

Its way above my pay grade

Same for me
on my yanmar generator (diesel) it was just a matter of pulling a wire. But then again there is no highly sofisticated electronics in there - it just runs - all.the.time.

[Moonlighter]

Yes, there might be issues disconnecting a key component of the system such as the alternator with the way modern engine electronics are integrated.

You are wise to check before acting rather than risk damage to expensive things like ecu’s.

[redlowrey]

It would probably be a good idea disconnecting the Suzuki charging system seeing he is running a lithium setup, the internal bums would be programmed at a maximum voltage of 14.6 volts and the Suzuki system between 14.5 and 15.2 volts.

If the Suzuki system ran an alternator that was field excited I would say just unplug the reg, but they use magnetic induction from the flywheel, so I don’t know if there would be any long term problems down the track.

Probably better talking to someone who deals with permanent magnet alternators, or remove the flywheel and remove the stator ass.

[redlowrey]

I missed the spelling it should read BMS not bums.

[2014DF25ARS]

I don't know the answer either, but If you remove the alternator, I believe you'll be forfeiting the option of hand-starting your motor on the awful day that your electrical system fails. Or the odd day when you want to be a hero and loan your little motor to another stranded boat. I have a DF25AR, and there have been a couple situations where I was cruising around with some other old/antique boats, and one of them had a dead battery. They were dead in the water, and I was able to give them my battery and then pull-start my motor and return home without a battery. My understanding is that the EFI Suzukis generate enough energy on the first pull to charge a capacitor and boot the EFI computer, then start and continue running on the second pull. That can be a very valuable feature on the rare occasion when you need it.

[Zabbaskeema]

Thanks for your feedback.
in the end I bought a small FLA battery that I will use as some kind of buffer in my lithium system/starter for the two df20atl and at the same time forget about any issues potentially set forth by the above question I had.

Cheers,