Balmar 60-100 fails to deliver amps with MC 614

[claptrap]

During our last passage something happened with our alternator. It now fails to deliver amps and the charge lamp is permanently lit.

When I put it in 'small engine mode' using the 614 regulator it delivers about 30A at 2000rpm.

In normal mode, it fails to ramp up the amps and the charge lamp is permanently lit. According to the manual this indicates 'no voltage on stator'.

Is this something that one can debug and fix, or do I need to get the alternator rebuilt or a replacement? I am having trouble understanding why it 'works' in small engine mode but not in normal mode.

[nuku34]

To the OP:
It would help us if you specified the details of the alternator: make and amps.
Do you have a temp sensor on the alternator?

Have you double checked the Balmar MC 614 settings? It looks complicated to do this using the magnetic screwdriver, but its not too hard and there are plenty of good vids to help. Marine How To has some very good advice and vids. https://marinehowto.com/programming-...age-regulator/



A simple check of the alternator is to temporarily apply full 12V voltage to the field of the alternator with the engine running at say 2000rpm.
First arrange a wire from any +12V source that can reach to the alternator. Then disconnect the Balmar from the alternator. Start the engine. Have someone watching the amps output. Momentarily touch +12V wire onto the field connection on the alternator. Amps should immediately jump to full rated output of the alternator. If alternator passes this test, the problem is the regulator.

[claptrap]

The alternator is a 60-100-SR-IG.
We had a temp sensor on there, but it failed sometime during the last voyage, however the batteries were full at that point so the alternator was no full-fielding for a long time and likely did not overheat (no smell or anything, the alternator passes all multimeter checks fine).
At some point it must have stopped producing power all together. The programming of the MC-614 has been working fine for years (!) and thousands of engine hours already.

I have since rewired the alternator to use the internal regulator (did not work) and back to external regulator. It now works again in normal mode and small engine mode. This suggests there is/was a loose connection on the wiring loom. I will have to replace all the extraneous plugs with butt connectors.

[sailorboy1]

I agree it is a wire issue since it worked in small engine mode. Check your fuse

[claptrap]

You mean the battery voltage sensing fuse? I'll double check that as well.

[nuku34]

To OP:
Happy to hear you found the fault. I've replaced all the Balmar reg and many of my Nani diesel electrical multi-pin plug connectors with waterproof butt connectors. Those plug connectors are only there for ease of connection (plug and play), but subject to corrosion and vibration.

[claptrap]

What about the 4-pin connector on the alternator itself? That one is at least 'sealed' with a silicone gasket...

[HuffinPuff]

Did you add Lithium batteries to your boat by any chance?

[claptrap]

The boat has had lithium batteries for 3y already and was full-time cruised during all that time. So there are plenty of cycles on that alternator/regulator/battery combo.

[sailorboy1]

Just on another note, the only time my alternator mystery stopped charging and I spend a bunch of time troubleshooting

It turned out to be the belt

[claptrap]

I have now dialed down the alternator using the belt load manager not to go over 50A (so no extended period full fielding) and am closely monitoring the temps until I can get a new temp sensor installed.

[tanglewood]

Maybe you have failing brushes?

[jdiazrv]

Small engine mode is achieved by shortening pins 5 and 6 of the MC-614.
Those same pins are the ones MC-614 uses to send temperature from alternator.
when mc-614 is operating check the scaling lcd. "AL" followed by a number is the alternator temperature. What is the value?
Does it work if you disconnect connectors to pin 5 and 6?
You can also put the mc614 in the long display mode (actually I believe in any case it is better to have it in that mode) and read what is the value of "FE". If FE is greater than 0 alternator should be producing amps.

[claptrap]

I have wired a switch to the pins to engage small engine mode and dialed the output down using the belt load manager so the temperature stays below 95 degrees celcius (measured at the back on the diode pack using an infrared temp sensor). That seems to work fine until i get a new temp sensor.

[Mickeyrouse]

I have had Balmar alternators for years. The 612 regulators never gave a problem, but the diodes in the alternator were constantly frying. I always carry a spare, necessary because it always seemed one was being rebuilt somewhere. Finally a quite knowledgeable repair dude convinced me to modify both alternators to “ single wire” thus using the internal regulator. That meant I no longer had access to the “ smart” features of the 612 regulators. It was also the end of my alternator troubles.