Balmar (and other premuim) alternator worth the expense?

[pwillems]

I believe I am going to be replacing my alternator very soon and am looking at options. It seems to me that there are some very big price differences between the standard and the more premium products.

For example, Bosch K1 120A for around AU$500 vs. Balmar 6 120A for around AU$1100.

Is the price difference here justified? In durability? In hot rating output?

[nhschneider]

My Aqua Marine Genset was originally equipped with a 150-amp Delco-Remy off-the-shelf alternator. About 600 operating hours ago, I replaced it with a brand new 150-amp Leece-Neville for US$180. The new alternator outputs the full amperage with less load on the engine. For the cost differential, you could buy several of the non-marine alternators, have plenty of back-ups and still have spent significantly less money.

Fair winds and calm seas.

[twinboat]

I went thru a few 150 amp specialty alternators with external 3 stage regulators. $200 US, every time it was rebuilt. Did that for 4 years, swapping in the OEM Mando 50 amp as my backup, until that failed.

I picked up a new 10SI Delco clone 105 amp alt from Amazon for $65 US and threw it on. Been 2 years and still going strong. I just ordered a spare 10SI. I cruise a bit slower the first hour to keep it under 85 to 90 amps but it seems to handle it.

[sv Winterlude]

When we wanted to upgrade from a 55 amp alternator to a 110 amp version, our diesel mechanic recommended a standard off the shelf Delco alternator. We put it in, bought a spare because we were headed offshore, replaced it ourselves plug & play in Mexico when it needed rebuilt several years later. Then had the original rebuilt... in Mexico. We used the rebuilt version in Panama a few years later, and had the 2nd one rebuilt. We still have the Panama rebuilt Delco on the boat and it's been 6 years. And the rebuilt rebuilt one as a spare.

Keep in mind, if you're headed to the Caribbean, it may not be easy to get spare parts and locals can almost always rebuild a "regular" off the shelf alternator. They're used to it.

I'd go Delco, but that's just our .02 cents.

[rwidman]

Originally Posted by twinboat

.......... I cruise a bit slower the first hour to keep it under 85 to 90 amps but it seems to handle it.

I would hate to have to base my speed on my alternator. This is something you shouldn't have to think about, it should just work in the background.

[geoleo]

Originally Posted by pwillems

I believe I am going to be replacing my alternator very soon and am looking at options. It seems to me that there are some very big price differences between the standard and the more premium products.

For example, Bosch K1 120A for around AU$500 vs. Balmar 6 120A for around AU$1100.

Is the price difference here justified? In durability? In hot rating output?

Balmar waste of $ get more solar

[sailorboy1]

Originally Posted by twinboat

I cruise a bit slower the first hour to keep it under 85 to 90 amps but it seems to handle it.

Check your regulator directions to see if you can derate the output.

I don't know if the Balmar are worth more money than others. I bet it it is at best a cost verse life thing. Kind of like the starter I got that was $85 instead of the OEM starter that was $600. People said it wouldn't last but it has been 5 years.

[a64pilot]

How do you guys externally regulate an off the shelf alternator?
How do you know the output of your alternators?

[twinboat]

Well I shouldn't be charging a 800 AH bank with a small frame alternator either.

That all I can fit in my old volvo, without hanging something on the side.

The high priced one would overheat and de-rate.

I cruise at 6 knots instead of my blazing 7.5 knots.

[twinboat]

Internal regulator. Balmar 3 stage in storage.

[twinboat]

Output is monitored by a TriMetric battery monitor

[a64pilot]

Originally Posted by twinboat

Output is monitored by a TriMetric battery monitor

I can see how that would work assuming of course no Solar or other charge sources, and I assume you see only what is going into the batteries? Meaning if your charging at 100 amps, but using 10 amps to run "stuff", your monitor will show a charge rate of 90?
I asked as I installed an ammeter on my alternator and I don't think many have, it of course measures alternator output directly, and I found what I suspected, that is at least in my case, you don't get say 150 amps out of a 150 amp alternator, you get significantly less, then as it heats up, output drops further assuming you have a temperature compensated regulator.
I'd rather this happen, than I had the thing burn up, so I'm not complaining, just making an observation.

[twinboat]

I have solar but it doesn't factor in, in early morning departures.

If the solar is charging, I make a mental note of its output and do some rough math.

The 105 amp "clone", SI 10 delco style, alternator I have outputs it's rating, even hot.

I thought the cheap alt would fail quickly but it keeps going. It was a temporary fix that I was using until I picked up an externally regulated replacement. Then enjoying life got in the way.

If your amps are dropping off, check the gauge of both the + and - cables coming from the alternator.

I have 4 or 6 gauge wire, right to the house bank bus bars.

[motion30]

I . bought a large frame l N alternator off of ebay for 60 bucks. It without put its full rated amperage Atlanta until I saw the boat

[Island Time O25]

Agree with twinboat. As a temp fix got a 110 amp Delco clone off of ebay for $70 thinking I'll have the Powerline which came with the boat rebuilt. But since then decided against that rebuild as too pricey. The clone's still working 3 seasons later. At $70 I can afford to replace it each season and will still come out ahead compared to buying a Motorola for $700.