Balmar (and other premuim) alternator worth the expense?

[BobFord]

Perhaps of interest- I have just replaced a Bosch 24v alternator for the second time in 3 years. About 300 hrs before they ' open circuit'.This one not in warranty so had it rewound. Sparky's comment ( in Aussie ) - " bloody things are now made in China , what do you expect? ". Surprised me , but the label clearly states ' Made in China'. I have asked Bosch to comment.

[TheThunderbird]

I have a 3Lt turbo charged Volvo TAMD 31-LA (1997) 130 HP

I am changing a silly power-Alt, and first changed the pulley from one to two 1/2" belts

Then I went searching for second hand large frame truck alt, but with no success (I found 100A at 40EUR)... till when a yard gave me an almost immaculate Bosch 150A 12 V made in GB ! (120EUR)

Still struggling for mounting it, possibly welding is needed on engine frame.

I will have a 150Ammeter on the B+, close to batteries!

And NO, no expensive regulators.... I intend to use it for BULK charge primarily, early in the morning, and then let the Solar do the filling up...

I will see how it goes...

[twinboat]

When I use the delco style small frame alternators, I have to drill out the mounting foot for the metric bolt.

They are built 3/8" and I bore them out to 7/16".

I have a Volvo Penta TAMD40B.

[roland stockham]

IMPORTANT - this only applies to standard deep cycle lead acid batteries (sealed or vented) other batt technologies need different charging setups if they have higher charge acceptance rates. (such as lithium or NiCad and some 'high tech' lead acids like cyclone cells)

Absolutely not, would not even consider one on most boats. The alternator output should be no more than 1/5 the battery capacity and 1/10 is fine so 10-20a for each 100a/hrs in the bank. Anything bigger gives little advantage and will rarely be used. The alternator output is governed buy the charge acceptance of the batteries not the alternator output. The most efficient charge is at the 10hr rate which will get you to 90% at about 14.8v. Up that to the 5hr rate with a higher output alternator and you are only at 80% when you get to 14.8v. The charge rate then drops dramatically so the time gained on the bulk charge is lost. There are time it can be worth it of course but not as often as you might think.
You can 'marinize' and alternator by opening it up a spraying with a high temp conformable coating and replacing steel bits with stainless, this is what high end ones do. But a standard auto is designed to run under the hood of a car with loads of salt spray from the wheels, they are pretty tough and personally never had one fail through corrosion.
Overheating is potentially an issue. It is said that standard auto alternators are not rated for the continuous high output you get from charging. This is tue but in prctice not usually a problem, here is why. On a car the rev limit is between 6-10,000 rpm so the alternator pulley is size for that speed, on a boat it is more likely 3-4,000. Most alternators don't develop full output until they are doing about 90% of there max speed so when you put a 100a alternator on a boat engine it is going to give about 60a max unless you do some major work on the belt pulleys. Effectively you have just de-rated it to an output it can continuously maintain without overheating!
So unless you run a batt bank above 750a/hr a standard 85-120a auto alternator is fine. Save the money and install a decent 3step regulator instead, will give you far more effective charging. I like the Sterling power ones but there are others.

[Jubilee39]

Originally Posted by Dockhead

Does anyone know whether Balmar actually do anything to that alternator besides stencil their brand name on it? Whether it's worth it or not probably depends on the answer to that question.

They don't indeed do anything to the SmartGauge battery monitor except double the .

No they dont. I ran a marine service shop for a while. I stockef Lestek alternators who built Balmar before Lestek was bought out and production went elsewhere. Occasionally Lestek would ship me my alternators painted and branded Balmar. These where the same alternators used in trucks and ambulances.

[Nicholson58]

we have 1.5 KW truck alternators 24 V. One on the engine, one on the Genset. Every big lightening strike has blown one or the other. Rebuild cost me 60 bucks at the alternator shop, a grungy place with alternators & starters stacked high in all the windows. A High end replacement is 1400 to 2400. ---- NOT HAPPIN'N. Re-build includes all 18 diodes, tear down, inspection of all coils & rotor windings, bench test.


I do have a Balmar charge controller. I recommend that or equal.

[RaymondR]

I standardized on Bosch Universal 85 amp alternators years ago, they are cheap and readily available and appear to abuse very well.

The first thing I do when I get a new one is solder 5 watt resisters onto the voltage sense and from-ignition-switch terminals so I don't accidently blow up the requlator.

You can change the regulator to a brush set if you want to run an external regulator, I usually just remove the standard regulator and solder a couple of wires onto the brush terminals when or if I want to externally regulate.

I have two alternators on the engine, one dedicated to the cranking batteries and one to the house. Gives me a readily available spare ready to go by changing a couple of terminals.

I have on occasions paralleled an alternator onto both banks using a bike spoke as an adjustable, heavy current resister but pretty well any fairly thin stainless wire or rod will do the job. Hang it up clear on anything so it will air cool and not set things alight.

There's a lot of very enjoyable, smug, gratification to be had by foiling the plans of those folks who peddle expensive "marine" stuff.

[SimonV]

Originally Posted by btrayfors

You can sometimes find very good prices on quality products, like the Balmar alternators.

Fifteen years ago I installed a BALMAR 100-AMP ALTERNATOR MODEL 912-100-D. I also installed a Balmar MC-612 external regulator. They have been rock solid for fifteen years.

I de-rate the alternator by 20%, using the option on the regulator. This means I never load the alternator to more than 80 amps. Since I have only a single 1/2" belt on my Perkins 4-108, this works very well. I don't burn up belts and the alternator isn't over-taxed.

Like the poster above, I also installed an ammeter on the alternator output. It's a big analog type mounted on the aft cabin bulkhead so I can see it from just about anywhere in the cabin, and see exactly how much amperage the Balmar is putting out at any time. On engine startup on the morning, after the 45-second ramp-up delay occasioned by the Balmar regulator, I see the ammeter needle peg on 80A and stay there for quite a while. Very reassuring.

Don't forget, batteries will only take the amount of charging amperage that they want, based on their state-of-charge, temperature, condition, charging voltage, etc. It doesn't matter how much amperage your charging sources can provide; the batteries themselves will determine how much they're going to take, at any fixed charging voltage.

And, while AGMs and gelled batteries can take a lot more charging amperage initially, it will still take them HOURS to reach a truly 100% charge....normally, much longer than you'd like to run your engine. That's why solar panels and/or frequent shoreside charging make sense, especially for AGMs which need frequent full charging.

Bill

Exactly the same as mine except my regulator is an SR4. I changed the drive belt after 7 years because I thought I should. I kept the old one as a spare.

Sent from my GT-N7105T using Cruisers Sailing Forum mobile app

[doublewide]

If u have AGM batteries then u need an externally regulated alternator like Balmar or you will quickly destroy your batteries through over charging. AGM batteries float at 13.3 V. Your OEM alternator probably charges at over 14 V. That is the best reason I know to buy a Balmar. Mine cost about $800 USD with regulators and temp probes for alt and batt. You really can't hang a much bigger alt on your engine and still drive it with a single pulley. Remember too that every 25 A costs you 1 HP. Trying for more amps is not a good reason to buy a Balmar.

[a64pilot]

Originally Posted by TheThunderbird

And NO, no expensive regulators

Not too bad price wise, so far it's been flawless for me

Mark Grasser - DC Power Solutions

[darylat8750]

Originally Posted by GordMay

For 10SI users, see: ➥ Catalog

Good link GordMay.
I point out that they don't recommend the large case for "high performance" applications BUT their version of high performance is cars stuff not boats. We have no issue with high rpm on our applications. Large case is much preferred if you have the room.

[donradcliffe]

Originally Posted by a64pilot

My guess would be your regulator isn't adjusted / set correctly, incorrectly installed maybe? I'd check that before I started buying parts.

If you want to know what you rexternal regulator is telling your alternator to do, simply measure the voltage between the field terminal and the alternator ground (case). If the batteries are discharged, the voltage will be at least 12v. If the batteries are charged, the voltage will be between 5 and 8 volts, depending on the electrical load.

[twinboat]

If you want to test the alternators output and hav an external regulator, put 12 volts to the field and watch the amps climb.

If you don't have an amp meter you can watch the volts climb, just a bit slower.