Most practical way to upgrade Yanmar alternator?

[roland stockham]

Very simply a 12v alternator will not charge a 12v battery without an external regulator. They are designed to provide axillary power and maintenance charge for vehicles, ALL OF THEM. A marine one simply means it has some corrosion protection, good cooling and connections already in place for the regulator. I like the Sterling Power one, cheap (under $200) simple and takes about an hour to fit. Will do all the things you want. Sterling Power USA : Advanced Marine Alternator Regulators

[Cheechako]

A proper regulator will do a much better job of charging. There's a huge difference in the different ones out there as far as initial amp output.
Having said that, you will likely find that 20 mins or so of max alternator output is about all you can do without burning up the alternator or the battery.
In theory all you need is voltage to the Field if you want to run the alternator to death without a regulator...
Cruising Equipt company used to sell an ammeter and big rheostat panel to adjust your field voltage and put out whatever you want. I think it disappeared due to liability reasons!

[a64pilot]

Originally Posted by rwidman

I don't think it's a wise idea to allow air from the cabin and engine room or bilge to mix for several reasons. Ducting air from outside the boat would be fine.

You know that is a given for power boats, I assume maybe it's because two big DD's would evacuate all the air conditioned air from a cabin in a real hurry, but I haven't seen hull vents like the "gills" you see on power boats, seems sail boat engines are mounted in the Salon actually and as far as I can tell the only place they can get air is from either the bilge or the salon.

[a64pilot]

Originally Posted by svlamorocha

Many thanks; that is great stuff.

The numbers are not as good as that because the 3YM20 only displaces 52 cubic inches and there are 1728 (not 144) cubic inches to a cubic foot, hence you only get 29 cf per minute of air coming in. Still, I have to try this because it is "free".

Obviously I confused square with cubed, should have knows the numbers were crazy, but you do understand the point.

[hellosailor]

"Very simply a 12v alternator will not charge a 12v battery without an external regulator."


Thank the Gods for mass hallucinations! I guess that's the only thing that's been keeping our batteries charged in so many places for so many years. I think I'll go try to find virgin electrician to make as burnt offering, in thanks.

[rwidman]

Originally Posted by a64pilot

You know that is a given for power boats, I assume maybe it's because two big DD's would evacuate all the air conditioned air from a cabin in a real hurry, but I haven't seen hull vents like the "gills" you see on power boats, seems sail boat engines are mounted in the Salon actually and as far as I can tell the only place they can get air is from either the bilge or the salon.

I don't know where sailboats get the air to run the engines but it seems sharing a salon or berth with a diesel would be pretty smelly and with gasoline, dangerous as well. And hot and loud with either.

But, I guess today is not a wasted day if I learned something.

[hellosailor]

"I don't know where sailboats get the air to run the engines but"
You need to get out more, Ron.
Most of us buy it, in large tins, freeze-dried to save space, at the local West Marine. Some folks try to home-brew it, but of course, that's an EPA violation as well.
And don't even think of using any out-of-state air in California, what's compliant in the other 49 states does NOT meet California CARB standards for marine engine use.

[rwidman]

Originally Posted by hellosailor

"I don't know where sailboats get the air to run the engines but"
You need to get out more, Ron.
Most of us buy it, in large tins, freeze-dried to save space, at the local West Marine. Some folks try to home-brew it, but of course, that's an EPA violation as well.
And don't even think of using any out-of-state air in California, what's compliant in the other 49 states does NOT meet California CARB standards for marine engine use.

Yea, that was a big help.

Sometimes when you have nothing to say, it's best to just not say it.

Is your engine in the saloon? Does it get its air from the saloon? Perhaps we can salvage your post.

[hellosailor]

No, most sailboats are too small to put the engine in the main cabin. It is normally under the companionway, behind the steps, and mainly under the cockpit. They draw air from leaky enclosures, partly from the cabin, but since that would mean NOISE in the cabin, most of the air comes from the stern vents, normally two, one feeding in fresh air low, the other removing hot air high. Perforated pegboard and other material often let the engine breath from (and heat and dry out) the lazarettes. Intake faces forward, exhaust faces aft. Over the years, owners may change that at random.

We don't use "gills" because with a typical freeboard of less than three feet and a boat that normally will be heeled and reduce that in half, gills would lead to rapid flooding of the boat.

Those engines that I've seen located in the main cabin (usually in the bilge when they are) normally are covered in a wood cabinet, and left to find what air they can drawing it from between the cabin sole and the hull or similar "highly engineered" solutions.

[Cheechako]

Originally Posted by hellosailor

"I don't know where sailboats get the air to run the engines but"
You need to get out more, Ron.
Most of us buy it, in large tins, freeze-dried to save space, at the local West Marine. Some folks try to home-brew it, but of course, that's an EPA violation as well.
And don't even think of using any out-of-state air in California, what's compliant in the other 49 states does NOT meet California CARB standards for marine engine use.

hah! I'm rollin'.........

[svlamorocha]

I think I found the alternator I was looking for.

Mark Grasser - DC Power Solutions

Has anyone had any experience with Mark Grasser´s alternators?

[svlamorocha]

Originally Posted by Cheechako

A proper regulator will do a much better job of charging. There's a huge difference in the different ones out there as far as initial amp output.
Having said that, you will likely find that 20 mins or so of max alternator output is about all you can do without burning up the alternator or the battery.
In theory all you need is voltage to the Field if you want to run the alternator to death without a regulator...
Cruising Equipt company used to sell an ammeter and big rheostat panel to adjust your field voltage and put out whatever you want. I think it disappeared due to liability reasons!

I do understand how regulators work and I can find many affordable regulators that will do well what I need (regulate absorption voltage and protect the alternator with temperature sensing) and more or less well something I do not need (switch to float) because of the way I use the boat.

My post is about alternators because I know that the Yanmar Hitachis have weaknesses (for cruising use) that no regulator can fix (namely for a given charge current they heat too much and do not withstand high temperature). The only reason I have not moved away from Hitachis so far is that I was not prepared to pay Balmar´s price for a hot-rated 100A alternator with 3.15" saddle mount and connectors for external regulation.

[sailinglegend]

Originally Posted by svlamorocha

...The only reason I have not moved away from Hitachis so far is that I was not prepared to pay Balmar´s price for a hot-rated 100A alternator with 3.15" saddle mount and connectors for external regulation.

I don't think you will find a non marine-rated alternator that will make you a happy bunny. Because of temperature compensation they will all reduce their output voltage, and therefore their output current very quickly when charging a house bank - especially Lifelines AGMs - even when the bank is nowhere near reaching its absorption voltage.

Even my Balmar series 6 regulator reduces it's output considerably, and very quickly, when working on its internal regulator only. Balmar recommend a switch to allow you to quickly switch to internal if the external regulator should fail, so I have done many tests on this.

I asked Balmar why the output falls when it gets hot and they explained there are two kinds of temperature regulation - I quote:

A few internal regulators will reduce the alternator output and voltage based upon the internal alternator temperature in order to protect the alternator.
The second is monitoring the temperature of the battery so the regulator can adjust the voltage to ensure the battery is being charged at the optimal voltage and not gas the battery or under charge the battery.

So the Balmar "assumes" the battery is in the engine compartment and will also be increasing in temperature, so it reduces its output. This should never happen on a boat!!

If you look at the modern alternator temperature compensation curves they reduce by so many mV per degree as the alternature temperature increases. The Yanmar voltage gradient is 0.01V/1ºC at 20°C, so at on 70ºC the voltage will be down to 13.9 volts! At 100ºC it will be down to 13.6 volts.

So the internal regulator needs to be disabled and an external alternator regulator added that will monitor and control the alternator output with an alternator temperature sensor. With a Balmar ARS5 external regulator it cuts the output by 50% at I think 105ºC. A battery temperature sensor and should also be used.

This is the only solution to get maximum charge current - ideally coupled with a "marine" alternator. If the budget doesn't allow a full upgrade go with the Hitachi until it finally gives up, but with only a 200Ah bank it might be ok.

According to Lifeline their AGMs will accept an in-rush current of 5C not 0.5C. This will not last for very long but will reduce to a charge current up to absorption of 1C or more, so with Lifeline AGMs you really are better off with a high current hot rated alternator.

A Marine Alternator', like the Balmar, is 'engineered' to provide its rated output current even at a temperature of over 100 degrees C, so it will maintain that output and charge the bank much quicker.

This 'hot rated engineering' may mean:

- High temperature diodes mounted on big heat sinks
- Heavier gauge stator windings
- Precision balanced rotor
- Copper composite brushes
- Heavy duty bearings with high temperature grease
- Corrosion resistant materials & coatings
- Dual cooling fans
- access to field windings
- tachometer output
- maybe an isolated ground terminal

All this comes at a much higher price - it's not just painting it in "Balmar" colours!

[svlamorocha]

Originally Posted by sailinglegend

I don't think you will find a non marine-rated alternator that will make you a happy bunny. Because of temperature compensation they will all reduce their output voltage, and therefore their output current very quickly when charging a house bank - especially Lifelines AGMs - even when the bank is nowhere near reaching its absorption voltage.

Even my Balmar series 6 regulator reduces it's output considerably, and very quickly, when working on its internal regulator only. Balmar recommend a switch to allow you to quickly switch to internal if the external regulator should fail, so I have done many tests on this.

I asked Balmar why the output falls when it gets hot and they explained there are two kinds of temperature regulation - I quote:

A few internal regulators will reduce the alternator output and voltage based upon the internal alternator temperature in order to protect the alternator.
The second is monitoring the temperature of the battery so the regulator can adjust the voltage to ensure the battery is being charged at the optimal voltage and not gas the battery or under charge the battery.

So the Balmar "assumes" the battery is in the engine compartment and will also be increasing in temperature, so it reduces its output. This should never happen on a boat!!

If you look at the modern alternator temperature compensation curves they reduce by so many mV per degree as the alternature temperature increases. The Yanmar voltage gradient is 0.01V/1ºC at 20°C, so at on 70ºC the voltage will be down to 13.9 volts! At 100ºC it will be down to 13.6 volts.

So the internal regulator needs to be disabled and an external alternator regulator added that will monitor and control the alternator output with an alternator temperature sensor. With a Balmar ARS5 external regulator it cuts the output by 50% at I think 105ºC. A battery temperature sensor and should also be used.

This is the only solution to get maximum charge current - ideally coupled with a "marine" alternator. If the budget doesn't allow a full upgrade go with the Hitachi until it finally gives up, but with only a 200Ah bank it might be ok.

According to Lifeline their AGMs will accept an in-rush current of 5C not 0.5C. This will not last for very long but will reduce to a charge current up to absorption of 1C or more, so with Lifeline AGMs you really are better off with a high current hot rated alternator.

A Marine Alternator', like the Balmar, is 'engineered' to provide its rated output current even at a temperature of over 100 degrees C, so it will maintain that output and charge the bank much quicker.

This 'hot rated engineering' may mean:

- High temperature diodes mounted on big heat sinks
- Heavier gauge stator windings
- Precision balanced rotor
- Copper composite brushes
- Heavy duty bearings with high temperature grease
- Corrosion resistant materials & coatings
- Dual cooling fans
- access to field windings
- tachometer output
- maybe an isolated ground terminal

All this comes at a much higher price - it's not just painting it in "Balmar" colours!

Many thanks; correciton taken on the Lifeline inrush current and everything understood and agreed, except that I am still trying to find an alternator with all that good stuff but for $400 or $500 instead of Balmar's $1000. I have not been able to get a quote from Rod aka Maine Sail but have one from Mark Grasser. Both of them make "marine hot rated alternators" that do everything you and I want.

The question left is: Do any CF members have experience with marine alternators from Maine Sail or Mark Grasser and how do they compare to Balmars?

[rwidman]

Originally Posted by hellosailor

No, most sailboats are too small to put the engine in the main cabin. It is normally under the companionway, behind the steps, and mainly under the cockpit. They draw air from leaky enclosures, partly from the cabin, but since that would mean NOISE in the cabin, most of the air comes from the stern vents, normally two, one feeding in fresh air low, the other removing hot air high. Perforated pegboard and other material often let the engine breath from (and heat and dry out) the lazarettes. Intake faces forward, exhaust faces aft. Over the years, owners may change that at random.

We don't use "gills" because with a typical freeboard of less than three feet and a boat that normally will be heeled and reduce that in half, gills would lead to rapid flooding of the boat.

Thanks. That sounds more reasonable. I've been on a few sailboats and never saw the engine. The last one belonged to a couple we met cruising and except for not having airconditioning, it seemed pretty luxurious.