Have a 2000 h410, 4 cylinder Yanmar with 80A alternator. Lives at a mooring during the season, rarely at a dock. My batteries do not seem to be charging adequately. Would appreciate advice. The setup is two banks of 2 6V golf carts each, and separate engine battery (with the standard solar panel to help charge it). One of the sets of golf carts is new last year. Boat spent the Winter in water, mostly on charge at a dock. This year I have noticed that the batteries never seem charged. After motoring for a few hours this weekend, for example, house voltage was only about 12.3 as soon as the engine was off. The voltage with engine on at cruising speed never exceeds 13 V. I think it was lower than that until last week when I tightened the belt on the alternator. Question is: is my alternator OK? What should the voltage be when the engine is up to speed, and/or is this being dragged down by dead batteries? Have I killed my batteries by undercharging them with a loose alternator for the past season or two? Appreciate advice from all you experts. Don't mind replacing a few batteries, but don't want to kill them off prematurely again. S/V Breathless h410 #250
what's killing my batteries?
- Thread starter Steve Feinsilver
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Not an expert, but it sounds like you are
undercharged if you are trying to charge with alternator only for a few hours. Suggest you get a Honda 2000 you will get 70+amps/ and plug it into your shore power receptacle. Your smart charger should do the rest and it will tell you when you are 80% charged (if you have a smart 3 stage charger). Second invest in a Link 20 type system so that you know the state of your batteries at all times, how many amps going in, voltage of batteries and so on. To answere your original question, I think my alternator on my H36 volts is around 13.3...keep in mind if you want to really know your voltage don't pay attention to your analog gauge, you need digital and the Link system really helps. You might post what kind of charger you have and if you do have a Links type system so that they next person may answere your questions better. Hopefully, if you did ruin your batteries the above suggestions might prevent it from happening again. Just my 2 cents
undercharged if you are trying to charge with alternator only for a few hours. Suggest you get a Honda 2000 you will get 70+amps/ and plug it into your shore power receptacle. Your smart charger should do the rest and it will tell you when you are 80% charged (if you have a smart 3 stage charger). Second invest in a Link 20 type system so that you know the state of your batteries at all times, how many amps going in, voltage of batteries and so on. To answere your original question, I think my alternator on my H36 volts is around 13.3...keep in mind if you want to really know your voltage don't pay attention to your analog gauge, you need digital and the Link system really helps. You might post what kind of charger you have and if you do have a Links type system so that they next person may answere your questions better. Hopefully, if you did ruin your batteries the above suggestions might prevent it from happening again. Just my 2 cents
Smart regulator
Standard alternators have automotive type regulators. They always undercharge batteries. Lead acid batteries should be charged to around 14.3 volts and kept at that level untill they will accept only about 5% of their rated size. EG 100 amp hour battery accepting less than 5 amps. Then a float cycle is started to keep the voltage constant around 13 volts. You MUST have a 3 stage charging regime if you want charged batteries and decent battery life. Forget generators, see Heart or Balmar for smart regs and chargers.
Standard alternators have automotive type regulators. They always undercharge batteries. Lead acid batteries should be charged to around 14.3 volts and kept at that level untill they will accept only about 5% of their rated size. EG 100 amp hour battery accepting less than 5 amps. Then a float cycle is started to keep the voltage constant around 13 volts. You MUST have a 3 stage charging regime if you want charged batteries and decent battery life. Forget generators, see Heart or Balmar for smart regs and chargers.
What I have found
I recently trouble shott my battery system. Hear is what I found. The solar panel was discharging the battery overnight. It suppose to have a diode to keep this from happening but it was not working for whatever reason. I plan to add a diode shortly as the panel puts out fine in the sun. Currently it is disconnected and the battery stays charged just fine. I also found the 110 volt charger was discharging the battery when not connected to shore power. I disconnected it when not charging the battery. I also found that if I leave the battery switched on and everything off it still draws a small amount. I now make sure I have it switched off when not using the boat.
I recently trouble shott my battery system. Hear is what I found. The solar panel was discharging the battery overnight. It suppose to have a diode to keep this from happening but it was not working for whatever reason. I plan to add a diode shortly as the panel puts out fine in the sun. Currently it is disconnected and the battery stays charged just fine. I also found the 110 volt charger was discharging the battery when not connected to shore power. I disconnected it when not charging the battery. I also found that if I leave the battery switched on and everything off it still draws a small amount. I now make sure I have it switched off when not using the boat.
Not my own opinion
I'm no expert. But, I went to a course given by one. He is Larry Berlin of Mack Boring, the Yanmar dealer. He recommends charging with a 3 stage charger preferably with temperature regulation from shore power. Also, if you charge with the engine you must run the engine at high RPM, no matter what type of charger is installed for it to effectively charge. This is almost a quote: If your're charging your battery at idle on your mooring you are doing almost nothing for the battery. This is a quote: "Be a power boater one weekend a month." I don't know if any of this applies to you but I hope it helps. Good course if you ever have the opportunity.
I'm no expert. But, I went to a course given by one. He is Larry Berlin of Mack Boring, the Yanmar dealer. He recommends charging with a 3 stage charger preferably with temperature regulation from shore power. Also, if you charge with the engine you must run the engine at high RPM, no matter what type of charger is installed for it to effectively charge. This is almost a quote: If your're charging your battery at idle on your mooring you are doing almost nothing for the battery. This is a quote: "Be a power boater one weekend a month." I don't know if any of this applies to you but I hope it helps. Good course if you ever have the opportunity.
misleading
First off...the engine uses an alternator...not a charger. Second of all, an alternator is putting out max electricity at about 1100 rpms...a little above idle. Third of all, a 3 stage charger isn't going to do any good when he is at a mooring unless he got a generator which is overkill. I don't know how many times I'm going to have to say this. Go solar. When you come out on Saturday morning the batteries will be fully charged (most likely). Run the engine a couple hours that weekend and then put it back on the mooring. When you come back out the following weekend (very few actually go each weekend) the batteries will be fully charged again (once again...most likely) and this is at a fraction of the cost of a generator. Now if he was a slip guy, then yeah, go get a nice charger to use the shore power.
First off...the engine uses an alternator...not a charger. Second of all, an alternator is putting out max electricity at about 1100 rpms...a little above idle. Third of all, a 3 stage charger isn't going to do any good when he is at a mooring unless he got a generator which is overkill. I don't know how many times I'm going to have to say this. Go solar. When you come out on Saturday morning the batteries will be fully charged (most likely). Run the engine a couple hours that weekend and then put it back on the mooring. When you come back out the following weekend (very few actually go each weekend) the batteries will be fully charged again (once again...most likely) and this is at a fraction of the cost of a generator. Now if he was a slip guy, then yeah, go get a nice charger to use the shore power.
Thanks to all
I knew I would get some interesting responses. I have no interest in an expensive charger as I rarely use shore power, prefer to anchor when cruising, and usually am at mooring. I have the same (fairly basic) AC charger that Hunter installed. In my experience, I agree that charging with the alternator is about the same at fast idle or high speed, at least judging by voltage. BTW I am using a VOM for all readings. My real question was is the voltage my alternator produces about right (12.8-13.0), is it my batteries fault, or should I suspect it is not working properly? But as long as I have some experts around- my h410 came with a solar panel connected to engine battery, which I think used to work. Lately, it doesn't seem to be doing much. Have checked the wiring. Should a six year old solar panel, or its charge controller, go bad? I have wondered whether the diode is working, or whether it is discharging the battery overnight. This should not affect the house battery banks. Have been thinking about replacing the solar panel with a bigger one, as big as will fit in its spot over the companionway, in which case I might wire it to the house banks as well, or maybe put in a switch to trickle charge whichever bank. Ideas? Thanks- S/V Breathless 2000 h410 #250
I knew I would get some interesting responses. I have no interest in an expensive charger as I rarely use shore power, prefer to anchor when cruising, and usually am at mooring. I have the same (fairly basic) AC charger that Hunter installed. In my experience, I agree that charging with the alternator is about the same at fast idle or high speed, at least judging by voltage. BTW I am using a VOM for all readings. My real question was is the voltage my alternator produces about right (12.8-13.0), is it my batteries fault, or should I suspect it is not working properly? But as long as I have some experts around- my h410 came with a solar panel connected to engine battery, which I think used to work. Lately, it doesn't seem to be doing much. Have checked the wiring. Should a six year old solar panel, or its charge controller, go bad? I have wondered whether the diode is working, or whether it is discharging the battery overnight. This should not affect the house battery banks. Have been thinking about replacing the solar panel with a bigger one, as big as will fit in its spot over the companionway, in which case I might wire it to the house banks as well, or maybe put in a switch to trickle charge whichever bank. Ideas? Thanks- S/V Breathless 2000 h410 #250
more help
Those panels that come with the boat don't last long. If you got 6 years out of it that's good. As for your alternator...yes...it should be putting out more volts but make sure your readings are correct before you replace it...they are expensive. I would go get a hard 100 watt solar panel and run that through a diode to a combiner.
Those panels that come with the boat don't last long. If you got 6 years out of it that's good. As for your alternator...yes...it should be putting out more volts but make sure your readings are correct before you replace it...they are expensive. I would go get a hard 100 watt solar panel and run that through a diode to a combiner.
charging
Steve, I have a 98 410 with same alternator/house bank you do. had a similiar problem last year, found the ground at the engine block and at the ground buss on the port side of the engine compartment were loose. I had about 5 ohms resistance between the engine block and the negative terminal on the house bank. after tightening these my alternator will now put out around 60 amps when the batteries will accept it. also make sure you have a ground strap from the alternator to the engine block ground. Bryce S/V Spellbinder H410
Steve, I have a 98 410 with same alternator/house bank you do. had a similiar problem last year, found the ground at the engine block and at the ground buss on the port side of the engine compartment were loose. I had about 5 ohms resistance between the engine block and the negative terminal on the house bank. after tightening these my alternator will now put out around 60 amps when the batteries will accept it. also make sure you have a ground strap from the alternator to the engine block ground. Bryce S/V Spellbinder H410
Charging
Steve, All of the other postetrs have good thoughts, but having worked through similar situations, I thought I might weigh in. First, the stock alternator is internally regulated and will not put out much more than 13.8V and will never fully charge your batteries. The cheapest alternative is to take the alternator to a shop and have rewired to accept an external regulator such as a Balmar 612. Since you are on a mooring, either a wind generator and/or a solar panel array will recharge your batteries and keep them charged when you are not using your boat. I found a 120W solar panel and an AirX Marine wind generator would produce about 80 ampHr/day. Finally, don't give up on the solar panel on the spray hood yet. First check the wiring as it is not uncommon for the companionway hatch to push against the wires causing them to fracture. Easy 20 minute fix with butt connectors. I also added a 1" thick block of teak to the lip on the companionway to keep the hatch away from the wires. I hope this helps.
Steve, All of the other postetrs have good thoughts, but having worked through similar situations, I thought I might weigh in. First, the stock alternator is internally regulated and will not put out much more than 13.8V and will never fully charge your batteries. The cheapest alternative is to take the alternator to a shop and have rewired to accept an external regulator such as a Balmar 612. Since you are on a mooring, either a wind generator and/or a solar panel array will recharge your batteries and keep them charged when you are not using your boat. I found a 120W solar panel and an AirX Marine wind generator would produce about 80 ampHr/day. Finally, don't give up on the solar panel on the spray hood yet. First check the wiring as it is not uncommon for the companionway hatch to push against the wires causing them to fracture. Easy 20 minute fix with butt connectors. I also added a 1" thick block of teak to the lip on the companionway to keep the hatch away from the wires. I hope this helps.
Only replaced one battery ..
goes against all that I have read. Most experts advise that all of your batteries should be of the same age and stored at the same temperature while charging. Am I way off base here?
goes against all that I have read. Most experts advise that all of your batteries should be of the same age and stored at the same temperature while charging. Am I way off base here?
That's what I've heard also
Buy all of them at the same time,charge and store together over the winter "warmer place like my garage" charge all once a month. I'm on my 5th year and still going strong. I've got two 90amp and a 105amp and have had no power issues. I only use both or 2 never on just one.
Buy all of them at the same time,charge and store together over the winter "warmer place like my garage" charge all once a month. I'm on my 5th year and still going strong. I've got two 90amp and a 105amp and have had no power issues. I only use both or 2 never on just one.
some results
Thanks for all the inputs. I have tightened and cleaned every connection I can find on the alternator, and now puts out about 13.5V- likely the best it will do. I have also purchased and installed a 65W hard solar panel, which fits pretty neatly on the area where the original panel was. I have removed the original panel (the wiring was OK, btw), and I wonder if it and/or the charge controller was the culprit. New charge controller with neat digital readout (another gauge to check). Put out 4 Amps on a not very sunny day late in the afternoon. This is about half of my total needs, with refrig and everything on. Another $1K to West Marine, but I love it. I know I committed a cardinal sin by replacing only one set of batteries last year, but it is only 1 year older than the other set, exactly the same, and they are completely separated except sometimes when charging. I think I may be finished with this project and will go back to actually sailing the boat for a while. S/V Breathless h410 2000 #250
Thanks for all the inputs. I have tightened and cleaned every connection I can find on the alternator, and now puts out about 13.5V- likely the best it will do. I have also purchased and installed a 65W hard solar panel, which fits pretty neatly on the area where the original panel was. I have removed the original panel (the wiring was OK, btw), and I wonder if it and/or the charge controller was the culprit. New charge controller with neat digital readout (another gauge to check). Put out 4 Amps on a not very sunny day late in the afternoon. This is about half of my total needs, with refrig and everything on. Another $1K to West Marine, but I love it. I know I committed a cardinal sin by replacing only one set of batteries last year, but it is only 1 year older than the other set, exactly the same, and they are completely separated except sometimes when charging. I think I may be finished with this project and will go back to actually sailing the boat for a while. S/V Breathless h410 2000 #250
batteries 12.3 volts
steve (doc) after reading your post ,I have the same boat as yours..... guesswhat same exact conditions. But I will bet you a bottle of rum that you realy do not have a problem with batteries???? When you shut off the engine the meter says 12.3 volts but if you take a digital volt meter and check at the battery terminal you will get 12.65 volts ??????? there if some res. going up the cable to the meter. your charging system also works ok . after I come back from the hunter party up in Mystic ct.this weekend and then Block IS. for a week ,I ll check into it further. 410 murphys law
steve (doc) after reading your post ,I have the same boat as yours..... guesswhat same exact conditions. But I will bet you a bottle of rum that you realy do not have a problem with batteries???? When you shut off the engine the meter says 12.3 volts but if you take a digital volt meter and check at the battery terminal you will get 12.65 volts ??????? there if some res. going up the cable to the meter. your charging system also works ok . after I come back from the hunter party up in Mystic ct.this weekend and then Block IS. for a week ,I ll check into it further. 410 murphys law
Don't forget the belt
A loose alternator belt will also keep you from charging your batteries. With the engine off you should not be able to grab a cooling fin on the alternator pully and turn the pully. Also look at the belt and area around it. If the belt is "pollished" on the contact side it is slipping. if you see "black fuzz" around either pully or the engine the belt is slipping.
A loose alternator belt will also keep you from charging your batteries. With the engine off you should not be able to grab a cooling fin on the alternator pully and turn the pully. Also look at the belt and area around it. If the belt is "pollished" on the contact side it is slipping. if you see "black fuzz" around either pully or the engine the belt is slipping.
thanks again for input
I feel I now know much more about my 12V system than I ever wanted to. Ken: I agree that the voltage at the battery is higher than at the panel by about 0.3V, discovered this myself last weekend. However, my batteries were going flat in no time, they really were not very charged, Think I may have fixed the problem by tightening belts and connections at alternator. I got ambititious and replaced the solar panel with a big one anyway (see photo in photoforum- I was so proud of this project). See you on the water (we often anchor in Cold Spring or West Harbor for weekend). Bill: Think I did help things by tightening belt- plan to replace it when I find a new one- original and 7 yrs old, probably time. S/V Breathless h410 #250
I feel I now know much more about my 12V system than I ever wanted to. Ken: I agree that the voltage at the battery is higher than at the panel by about 0.3V, discovered this myself last weekend. However, my batteries were going flat in no time, they really were not very charged, Think I may have fixed the problem by tightening belts and connections at alternator. I got ambititious and replaced the solar panel with a big one anyway (see photo in photoforum- I was so proud of this project). See you on the water (we often anchor in Cold Spring or West Harbor for weekend). Bill: Think I did help things by tightening belt- plan to replace it when I find a new one- original and 7 yrs old, probably time. S/V Breathless h410 #250
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