What are some things that people have done to charge the batteries on their boat besides the motor. I have an O'day 22 and I finally got a motor for it but the problem is that I don't think it has the capability to charge the batteries. I will be running a Garmin 215 chart plotter off it as well as lights and possibly a stereo and various other electronic devices. The motor is a 1984 Johnson 7.5 long shaft. Is there a way to get the motor to charge the batteries? What about solar power. This is a tight budget boat and I am looking for the cheapest possible way to do it. Any ideas would be appriciated. If someone has a motor with an alternator that they would like to trade that would also be great. All Ideas are welcome.
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$49.99 solar panel
Hello, I used this when my Catalina 22 was ona mooring: http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=41144 I would connect it when I left the boat and store it when I was using the boat. On my C22 all I had was a VHF radio, running lights and interior lights. I only used the lights for the occassional night sail. Since most of the time the boat just sat on the mooring, the solar panel was easily able to keep up. I don't think it would work for a week cruise, but I didn't need it too. Barry
Hello, I used this when my Catalina 22 was ona mooring: http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=41144 I would connect it when I left the boat and store it when I was using the boat. On my C22 all I had was a VHF radio, running lights and interior lights. I only used the lights for the occassional night sail. Since most of the time the boat just sat on the mooring, the solar panel was easily able to keep up. I don't think it would work for a week cruise, but I didn't need it too. Barry
Outboard alternator
Outboards specifically designed for sailboats have alternators. I don't think you can add one but keep in mind when upgrading that these motors are out there. They work well.
Outboards specifically designed for sailboats have alternators. I don't think you can add one but keep in mind when upgrading that these motors are out there. They work well.
We use solar panels
We have 2 of the $49.00 panels, hooked in parallel, I wouldn't change a thing. Tom s/v GAIA
We have 2 of the $49.00 panels, hooked in parallel, I wouldn't change a thing. Tom s/v GAIA
Charging on Johnson 7 1/2 ...
is probably possible. You will need a rectifier kit at the very minimum (about 50 bucks, around that for labor), and possibly some magnets to attach to the flywheel (more money, more labor). I have the manual for these years of Johnson, and a 7.5 is not listed for 1984, by the way, but was manufactured in 1983. They only made a 6 and an 8 in 1984 (if my specifications history is correct). I show that from 1980-1983 the 7.5 came with a "Type II flywheel magneto ignition with Sensor Coil." The instructions in this section of my manual are not very helpful in determining the precise nature of the equipment, but I believe that connecting the sensor to either a rectifier or a charging coil assembly will likely work. Call the dealer and hope that they will be willing to do this for a reasonble price. I just had this done to a 2000 Yamaha, but I don't know about the labor on your model. Mine was free as part of the dealer's desire to unload this motor that had been on their floor for five years.
is probably possible. You will need a rectifier kit at the very minimum (about 50 bucks, around that for labor), and possibly some magnets to attach to the flywheel (more money, more labor). I have the manual for these years of Johnson, and a 7.5 is not listed for 1984, by the way, but was manufactured in 1983. They only made a 6 and an 8 in 1984 (if my specifications history is correct). I show that from 1980-1983 the 7.5 came with a "Type II flywheel magneto ignition with Sensor Coil." The instructions in this section of my manual are not very helpful in determining the precise nature of the equipment, but I believe that connecting the sensor to either a rectifier or a charging coil assembly will likely work. Call the dealer and hope that they will be willing to do this for a reasonble price. I just had this done to a 2000 Yamaha, but I don't know about the labor on your model. Mine was free as part of the dealer's desire to unload this motor that had been on their floor for five years.
and Steve...
...don't expect much juice. Skip the stereo and buy a battery boom box. The chart plotter alone will, by the time you factor in line voltage drop, consume half (or thereabouts) of your power.
...don't expect much juice. Skip the stereo and buy a battery boom box. The chart plotter alone will, by the time you factor in line voltage drop, consume half (or thereabouts) of your power.
Volkswagen Dealer...
New Volkswagens ship with a 12 volt solar panel battery charger to keep the battery up while in transit and storage. Plugs into a lighter socket. In the cars it is held to the inside of the windshield with 4 suction cups. Easy on/off. Great for cars, SUV's, boats, campers and RVs. Panel produces 18.8 volts 3.2 watts @170 m amps. This is perfect for maintaining a battery charge on a car, boat, or truck that is not used daily. Will work with any 12 volt system. I bought one on eBay for $10.00. If you know a VW dealer you might be able to get a dozen of them for nothing. I use one in my truck in the winter when it gets nasty in Minnesota and in my H23 in the summer. I'm not running a stereo of the 12 volt system though.
New Volkswagens ship with a 12 volt solar panel battery charger to keep the battery up while in transit and storage. Plugs into a lighter socket. In the cars it is held to the inside of the windshield with 4 suction cups. Easy on/off. Great for cars, SUV's, boats, campers and RVs. Panel produces 18.8 volts 3.2 watts @170 m amps. This is perfect for maintaining a battery charge on a car, boat, or truck that is not used daily. Will work with any 12 volt system. I bought one on eBay for $10.00. If you know a VW dealer you might be able to get a dozen of them for nothing. I use one in my truck in the winter when it gets nasty in Minnesota and in my H23 in the summer. I'm not running a stereo of the 12 volt system though.
84 7.5E
I have a 84 Mercury 7.5E. If your outboard has electric start it more than likely also has a rectifier. I pretty much have the same load on my battery and the outboard has been able to keep up with it.
I have a 84 Mercury 7.5E. If your outboard has electric start it more than likely also has a rectifier. I pretty much have the same load on my battery and the outboard has been able to keep up with it.
Solar Panel
I have a 32 watt solar panel. On a sunny day, it will run my depth finder, am/fm, VHF, and keep the battery fully charged. If there are any stars out, it will run my anchor light. I did drop $350 for the panel and controller.
I have a 32 watt solar panel. On a sunny day, it will run my depth finder, am/fm, VHF, and keep the battery fully charged. If there are any stars out, it will run my anchor light. I did drop $350 for the panel and controller.
A second battery
The cheapest way to go is to buy another battery or maybe even two. This assumes that you are using your boat primarily on weekends for an overnight and that you have access toshore power to recharge the batteries. The small solar panels put out very few amps. this is OK to maintain a battery but not enough to quickly recharge. Do the math a 32 wat charger at 15 amps puts out 2 amps under ideal conditions. this is usually from about 10 am to 2 pm or about four hours that's 8 amp hours a day. We'll be generous and say that you can get 12 amp hours a day. Most anchor lights pull about 1 amp for 10 hours so that leaves you with 2 amp hours not even enough to run your depth sounder. But a 115 amp hour battery fully charged should easily give you 60 amp hours. And you can buy one at Wal-mart for about $60.00. I am not against solar panels especially if you don't have shore power but the cheapest way to add amp hours is to add a battery. Tom
The cheapest way to go is to buy another battery or maybe even two. This assumes that you are using your boat primarily on weekends for an overnight and that you have access toshore power to recharge the batteries. The small solar panels put out very few amps. this is OK to maintain a battery but not enough to quickly recharge. Do the math a 32 wat charger at 15 amps puts out 2 amps under ideal conditions. this is usually from about 10 am to 2 pm or about four hours that's 8 amp hours a day. We'll be generous and say that you can get 12 amp hours a day. Most anchor lights pull about 1 amp for 10 hours so that leaves you with 2 amp hours not even enough to run your depth sounder. But a 115 amp hour battery fully charged should easily give you 60 amp hours. And you can buy one at Wal-mart for about $60.00. I am not against solar panels especially if you don't have shore power but the cheapest way to add amp hours is to add a battery. Tom
David, could you tell me more?
Actually I think it is a 83, you seem to know your stuff. I think your idea is the most promising and cost effective. The motor is in great condition and has 110lbs of compression so I think I will have it for a while. would you mind going a little more in depth with me? Such as what parts I should be looking for and what I should look for on the motor. This is the most ideal way to make this work. What you are saying is that it could be as easy as attaching a rectifier or a charging coil to the sensor coil, I might be able to draw some electricity from the motor. Wouldn't I be steeling from the spark though? Or what I would hope is that the motor came with the capibility to add the rectifier as an option back in the day. Do you know if that might be the case?
Actually I think it is a 83, you seem to know your stuff. I think your idea is the most promising and cost effective. The motor is in great condition and has 110lbs of compression so I think I will have it for a while. would you mind going a little more in depth with me? Such as what parts I should be looking for and what I should look for on the motor. This is the most ideal way to make this work. What you are saying is that it could be as easy as attaching a rectifier or a charging coil to the sensor coil, I might be able to draw some electricity from the motor. Wouldn't I be steeling from the spark though? Or what I would hope is that the motor came with the capibility to add the rectifier as an option back in the day. Do you know if that might be the case?
Go Solar
The chargers built into a small outboard produce such a small output that you would have to run your motor for about 6-8 hours for it to recharge your battery after using lights, radio, VHF, GPS, etc. If it was just charging a starting battery it wouldn't take long to charge up unless you really have to crank on it to get the motor started. So the moral of the story is, If you are going to have to motor for hours to charge the battery, Buy a power boat Just my two cents. Dave
The chargers built into a small outboard produce such a small output that you would have to run your motor for about 6-8 hours for it to recharge your battery after using lights, radio, VHF, GPS, etc. If it was just charging a starting battery it wouldn't take long to charge up unless you really have to crank on it to get the motor started. So the moral of the story is, If you are going to have to motor for hours to charge the battery, Buy a power boat Just my two cents. Dave
Not cheap but effective
Steve, My boat is an O'day 272LE with a 10hp Universal diesel engine. My dock did not have shore power so I supplemented my engine charger with an 50 watt solar panel, purchased on Ebay for $200 + about $40 for a charge controller. I only run the motor to get in and out of the slip or on days when I need an iron sail. I have the typical loads... lights, stereo, etc. I also have a 1000w inverter that runs a microwave and tv (for the kids). I use the boat about 3 times a week running most of the loads. I have 2, group 31 batteries that I don't have to charge all summer. The benetfit of solar over an alternator is that your batteries are charging even when you aren't on the boat.
Steve, My boat is an O'day 272LE with a 10hp Universal diesel engine. My dock did not have shore power so I supplemented my engine charger with an 50 watt solar panel, purchased on Ebay for $200 + about $40 for a charge controller. I only run the motor to get in and out of the slip or on days when I need an iron sail. I have the typical loads... lights, stereo, etc. I also have a 1000w inverter that runs a microwave and tv (for the kids). I use the boat about 3 times a week running most of the loads. I have 2, group 31 batteries that I don't have to charge all summer. The benetfit of solar over an alternator is that your batteries are charging even when you aren't on the boat.
AC Lighting/7.5 Johnson
Steve... I studied the section on this, and must say I would call an experienced dealer to make sure that I am right, 'cause I'm not sure. Having said that, the wiring diagram in my manual for this type of ignition shows that this model had the option for "AC Lighting." However, the wiring diagram also generically applies to every motor from 4 to 50 HP that used this type of ignition. I did verify your ignition type, so I do believe it is safe to assume that you can make this work. After looking at the pictures of flywheel work on this ignition type, and reading the instructions, I believe the best thing is to install a separate AC lighting coil under the flywheel and a rectifier to convert it to DC current. However, the wiring diagram I had did not show the separate lighting coil on the "AC Lighting" models, only the addition of a three wire rectifier, but the place where DC charging output was to be tapped off the circuit was not even mentioned, so I must wring my hands. Anyway, there is room under the flywheel to mount an AC lighting coil, and the rectifier unit could attach anywhere. My conclusion: If you're going to bother, install a separate AC lighting coil and rectifier and don't tap into the ignition circuit with a rectifier. You will be able to generate 5 or 6 amps for your electrical system that way. It's not worth doing to generate 2 - 3 amps. I expect that this retrofit will require the ordering of obtainable but not easily obtainable equipment, and probably about 1 1/2 hours of labor ($65 an hour). I'll guess $200 after studying the situation a little more. Again, you need to phone a dealer who works with OMC/Johnson and verify my opinion, and particularly the amperage output for either way and see if they will do the work. If all I've said is accurate above, this is a pretty good solution for a few years. I would make sure that the compression difference between the cylinders was at the most 10 pounds, however.
Steve... I studied the section on this, and must say I would call an experienced dealer to make sure that I am right, 'cause I'm not sure. Having said that, the wiring diagram in my manual for this type of ignition shows that this model had the option for "AC Lighting." However, the wiring diagram also generically applies to every motor from 4 to 50 HP that used this type of ignition. I did verify your ignition type, so I do believe it is safe to assume that you can make this work. After looking at the pictures of flywheel work on this ignition type, and reading the instructions, I believe the best thing is to install a separate AC lighting coil under the flywheel and a rectifier to convert it to DC current. However, the wiring diagram I had did not show the separate lighting coil on the "AC Lighting" models, only the addition of a three wire rectifier, but the place where DC charging output was to be tapped off the circuit was not even mentioned, so I must wring my hands. Anyway, there is room under the flywheel to mount an AC lighting coil, and the rectifier unit could attach anywhere. My conclusion: If you're going to bother, install a separate AC lighting coil and rectifier and don't tap into the ignition circuit with a rectifier. You will be able to generate 5 or 6 amps for your electrical system that way. It's not worth doing to generate 2 - 3 amps. I expect that this retrofit will require the ordering of obtainable but not easily obtainable equipment, and probably about 1 1/2 hours of labor ($65 an hour). I'll guess $200 after studying the situation a little more. Again, you need to phone a dealer who works with OMC/Johnson and verify my opinion, and particularly the amperage output for either way and see if they will do the work. If all I've said is accurate above, this is a pretty good solution for a few years. I would make sure that the compression difference between the cylinders was at the most 10 pounds, however.
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