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#1
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Battery heresy
Calder points out how battery life is increased by minimizing
discharge level. No matter how many batteries you have in the boat, you'll get maximum life by putting them in one bank. Keeping a starting battery isolated and in reserve is obviously a necessary compromise for most craft. However, with a 20 hp diesel, modest starting loads, and the ability to hand start, I'm thinking that the simplicity of a one bank system might make sense for a daysailing, short cruise boat, that is docked with shore power. If the batteries did get run down away from home, I'd be willing to hand start in penance. The key question is whether a two cylinder diesel like a 20 hp Yanmar 2QM can really be hand started or if it is an "only when your life absolutely depends on it" kind of operation. I don't have much experience with engines under 200 HP so I'd appreciate the benefit of actual experience. -- Roger Long |
#2
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Roger Long wrote:
Calder points out how battery life is increased by minimizing discharge level. No matter how many batteries you have in the boat, you'll get maximum life by putting them in one bank. Keeping a starting battery isolated and in reserve is obviously a necessary compromise for most craft. However, with a 20 hp diesel, modest starting loads, and the ability to hand start, I'm thinking that the simplicity of a one bank system might make sense for a daysailing, short cruise boat, that is docked with shore power. If the batteries did get run down away from home, I'd be willing to hand start in penance. The key question is whether a two cylinder diesel like a 20 hp Yanmar 2QM can really be hand started or if it is an "only when your life absolutely depends on it" kind of operation. I don't have much experience with engines under 200 HP so I'd appreciate the benefit of actual experience. Are you sure your engine is set up for hand starting? The heat exchanger version of the 2GM certainly isn't, because the water pump blocks the spot the crank would go into. Even if this were not the case, I don't think either of my engines are installed such that a crank could be swung. I'll be curious to hear the replies - although some will say it can be done, I've only heard a few people say they have actually done it. |
#3
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Are you sure your engine is set up for hand starting?
Yes, I saw the crank. It's the raw water cooled version. I have the service manual and it shows a hand crank setup for the fresh water version as well. I hear from another source that it's a rather athletic undertaking and a second person to close the compression release is a necessity. Also heard from another owner of the same boat who has run it exactly the way I describe for 17 years without a problem. I think I'll just leave the battery switch on boat all the time. -- Roger Long |
#4
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Are you sure your engine is set up for hand starting?
Roger Long wrote: Yes, I saw the crank. It's the raw water cooled version. I have the service manual and it shows a hand crank setup for the fresh water version as well. What the manual shows may not match what's on the boat. I've had a boat with a hand-startable diesel (a one-cylinder Volvo) that had various bits of the cabin in the way of the hand crank. I hear from another source that it's a rather athletic undertaking and a second person to close the compression release is a necessity. The only times I've ever successfully hand-started a diesel, it was necessary to manipulate the compression release. Also heard from another owner of the same boat who has run it exactly the way I describe for 17 years without a problem. I think I'll just leave the battery switch on boat all the time. You might want to visit him on his boat and get a demo. Another option http://www.springstarter.com/ Fresh Breezes- Doug King |
#5
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Another option
http://www.springstarter.com/ Hey, that is very, very cool. BTW it's a used boat. I inspected it personally and tried the crank in position. One of the first things I'm going to do is try and start it. I'll let you know how it goes. -- Roger Long |
#6
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Roger Long wrote:
Another option http://www.springstarter.com/ Hey, that is very, very cool. BTW it's a used boat. I inspected it personally and tried the crank in position. One of the first things I'm going to do is try and start it. I'll let you know how it goes. If you inboard is hand crank equipped like mine was on a previous boat, you REALLY don't need to hand crank it when the battery runs down. I killed my battery at anchor a few times (thank you Espar!). No problem. As long as you have two people aboard: 1 person lifts the decompression lever, which makes the engine turn over fairly easily. The second person pushes the start switch and once the engine is moving and the flywheel is doing it's job, just drop the decompression lever and she'll start like a charm. Hand cranking was never required and I killed the battery sufficiently that the lights were dim. I left the Espar running all night in cold fall weather. |
#7
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"Roger Long" wrote in message .. . Are you sure your engine is set up for hand starting? Yes, I saw the crank. It's the raw water cooled version. I have the service manual and it shows a hand crank setup for the fresh water version as well. I hear from another source that it's a rather athletic undertaking and a second person to close the compression release is a necessity. Once the compression levers are opened, an 8 year old can crank it. You don't need another person to handle the levers since they lock in the open position. Just get it spinning and reach up and close one lever. Then throw the other lever(s). I started my 3HM30 and 3GM30 this way several times. You can also start them using a string of a few D-cells. Also heard from another owner of the same boat who has run it exactly the way I describe for 17 years without a problem. I think I'll just leave the battery switch on boat all the time. -- Roger Long |
#8
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"Marley" wrote in message .. . Roger Long wrote: Another option http://www.springstarter.com/ Hey, that is very, very cool. BTW it's a used boat. I inspected it personally and tried the crank in position. One of the first things I'm going to do is try and start it. I'll let you know how it goes. If you inboard is hand crank equipped like mine was on a previous boat, you REALLY don't need to hand crank it when the battery runs down. I killed my battery at anchor a few times (thank you Espar!). You should thank yourself. The ESPAR had your permission to run No problem. As long as you have two people aboard: Depends upon the engine. Both of my previous Yanmars could be crank started by one person. 1 person lifts the decompression lever, which makes the engine turn over fairly easily. The second person pushes the start switch and once the engine is moving and the flywheel is doing it's job, just drop the decompression lever and she'll start like a charm. What does the start switch have to do with it? Hand cranking was never required and I killed the battery sufficiently that the lights were dim. I left the Espar running all night in cold fall weather. With the decompression levers engaged, it doesn;t take much to get the engine spinning enough to start. |
#9
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Is there some trick to starting? I just heard from someone on the
owner's forum for my boat, the only one responding who had tried hand starting, and he said he spent an entire summer bashing knuckles and getting thrown across the cabin without ever getting it going. He was using the compression releases, trying one cylinder at time, etc. What could he have been doing wrong? -- Roger Long |
#10
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On Tue, 15 Mar 2005 17:14:56 -0500, Marley wrote:
If you inboard is hand crank equipped like mine was on a previous boat, you REALLY don't need to hand crank it when the battery runs down. I killed my battery at anchor a few times (thank you Espar!). No problem. As long as you have two people aboard: 1 person lifts the decompression lever, which makes the engine turn over fairly easily. The second person pushes the start switch and once the engine is moving and the flywheel is doing it's job, just drop the decompression lever and she'll start like a charm. Since I normally single-hand, on a previous boat I installed a starter button in the engine compartment specifically for this reason - if the battery was too low to crank against the engine compression, I could open the engine room, lift the decompression lever, then press the handy start button - with luck, the weak battery would then be able to crank the engine, and once it was turning fast, I would drop the decompression lever, and the engine would (hopefully) start. -- Peter Bennett, VE7CEI peterbb4 (at) interchange.ubc.ca new newsgroup users info : http://vancouver-webpages.com/nnq GPS and NMEA info: http://vancouver-webpages.com/peter Vancouver Power Squadron: http://vancouver.powersquadron.ca |
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