26M - Battery Compartment?

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JeffJuneau
Engineer
Posts: 154
Joined: Mon Jul 20, 2020 11:37 am
Sailboat: MacGregor 26M
Location: Juneau, Alaska 2009 26M 70hp Suzuki

Re: 26M - Battery Compartment?

Post by JeffJuneau »

Thanks OverEasy and Be Free, You two are a amazing, and I don’t think there is any question about Macs that you can’t answer. So, again I don’t know if the fellow from Florida who started this thread is getting anything out of this battery discussion, but I am just following up on the last two posts that are in reference to my 26M battery situation. Be Free, my knowledge of batteries and DC could fit in a thimble, so please bear with me on my uninformed questions/information. I checked the Suzuki literature for the DF70A too, and it cites the minimum CCA as 512 Amps. So your right, 512 isn’t very far from the 550 CCA that I have, but since the batteries are virtually new (and have been kept charged), and seem to quickly take a full charge from the Pro Mariner ProSport 12 HD battery charger I just installed, which also says that the batteries pass all the charging tests it performs, hopefully I have a while before they are not adequate. When they start to have difficulty taking a charge, I will probably ask this group what I should replace them with, that has the same dimensions of my current battery that nicely fits the SS straps that came with BWY battery containment setup. I had the batteries out for a couple of months, and I wish I had taken some images of them out of the 26M battery containment compartment. I can still see the 550 CCA on the top but since they are all clamped down now with some effort, and crammed into that little space, I don’t want to go through taking that off for a while. So a lot of the other capacity information is now obscured so I can’t verify which exact battery it is. I am sure that these are not starting batteries, but I also don’t think they are true deep cycle. I think the PO said they are some type of compromise between those two purposes. So perhaps they can only be discharged by 20% at a time. I have a battery voltmeter installed and assume that there is some corresponding DC volts at which I should no longer count on the battery to produce 512 CCA. Maybe I can just check that before starting them. Since these interstate batteries were made for Costco, you might not be able to find the exact duplicate in the interstate literature. They are from fall 2019, and sometimes box stores have specific specs for things they order from manufacturers in bulk that don’t perfectly match what they distribute to other buyers. Also, all of the lights on my 26M are LED, so hopefully I am drawing less than your estimates. Also, on many nights, you can still read a newspaper at about midnight in Juneau during my limited sailing season.

OverEasy, the information you provided on resins is very helpful. I will probably apply your shoe box cardboard method to make something that contains fluid from a battery spill out of epoxy resin sometime in the not-too-distant future. I note that only one of three 26M owners responding to the original post even had battery boxes in their 26M’s, and by extension, perhaps only 1/3 of 26M owners on this forum have actual battery spill containment. Oh, I have one of those Lithium Polymer portable 12V starting packs too, but from some previous posts on this forum, I thought that the little hand-held ones too are limited in CCA to the extent that they would not work for starting a DF70A? It would be nice to find out that is not the case. Jeff
OverEasy
Admiral
Posts: 2012
Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26M - Battery Compartment?

Post by OverEasy »

Hi JeffJuneau

A lot of times the engine CCA is just that, 🥶🌬COLD 🌬🥶 , which in your case is probably a lot more cold :o :? :o than
what we get for cold in SC :D :D and we’re doing our best not to be in NH when it is :D :D

That means often times one doesn’t need the full amperage to get started in say July vs. January.
Kind of a curve that more amps are needed when cold and the battery has less, like when you have to get up early the go to work for an important meeting in February…. :o :D :P … at least that was my luck…. :P :cry: :? :o :D

As far as the jump pack they generally have a rating on them or in the paperwork.
What I did as a “wonder what happens if” I tried out one in place of the battery entirely JUST to start it.
It worked! :) :)
Then I shut it off and put the battery back in my buddy’s truck.

If you have a depleted battery and you clip the jump pack in parallel both the jump pack and what’s left in the depleted battery will try to work together to start the engine. I wouldn’t leave the jump pack connected any longer than necessary.

Your engine when running should be charging your dual purpose batteries.
We currently have a start battery AND a dual purpose.
The PO put the start battery in and it should last 4 or 8 more years with TLC.
Eventually when it does fizzle we will replace it with a dual purpose.

We would dearly like to get an anchor drum winch which may necessitate a 3rd battery to absorb the current requirements.
Currently we have no idea where we would put it…..🤔


8) 8) 🐩
Last edited by OverEasy on Tue Jul 27, 2021 4:19 pm, edited 2 times in total.
JeffJuneau
Engineer
Posts: 154
Joined: Mon Jul 20, 2020 11:37 am
Sailboat: MacGregor 26M
Location: Juneau, Alaska 2009 26M 70hp Suzuki

Re: 26M - Battery Compartment?

Post by JeffJuneau »

Thanks OverEasy and Be Free, You two are a amazing, and I don’t think there is any question about Macs that you can’t answer. So, again I don’t know if the fellow from Florida who started this thread is getting anything out of this battery discussion, but I am just following up on the last two posts that are in reference to my 26M battery situation. Be Free, my knowledge of batteries and DC could fit in a thimble, so please bear with me on my uninformed questions/information. I checked the Suzuki literature for the DF70A too, and it cites the minimum CCA as 512 Amps. So your right, 512 isn’t very far from the 550 CCA that I have, but since the batteries are virtually new (and have been kept charged), and seem to quickly take a full charge from the Pro Mariner ProSport 12 HD battery charger I just installed, which also says that the batteries pass all the charging tests it performs, hopefully I have a while before they are not adequate. When they start to have difficulty taking a charge, I will probably ask this group what I should replace them with, that has the same dimensions of my current battery that nicely fits the SS straps that came with BWY battery containment setup. I had the batteries out for a couple of months, and I wish I had taken some images of them out of the 26M battery containment compartment. I can still see the 550 CCA on the top but since they are all clamped down now with some effort, and crammed into that little space, I don’t want to go through taking that off for a while. So a lot of the other capacity information is now obscured so I can’t verify which exact battery it is. I am sure that these are not starting batteries, but I also don’t think they are true deep cycle. I think the PO said they are some type of compromise between those two purposes. So perhaps they can only be discharged by 20% at a time. I have a battery voltmeter installed and assume that there is some corresponding DC volts at which I should no longer count on the battery to produce 512 CCA. Maybe I can just check that before starting them. Since these interstate batteries were made for Costco, you might not be able to find the exact duplicate in the interstate literature. They are from fall 2019, and sometimes box stores have specific specs for things they order from manufacturers in bulk that don’t perfectly match what they distribute to other buyers. Also, all of the lights on my 26M are LED, so hopefully I am drawing less than your estimates. Also, on many nights, you can still read a newspaper at about midnight in Juneau during my limited sailing season.

OverEasy, the information you provided on resins is super helpful. I will probably apply your shoe box cardboard method to make something that contains fluid from a battery spill out of epoxy resin sometime in the not-too-distant future. I note that only one of three 26M owners responding to the original post even had battery boxes in their 26M’s, and by extension, perhaps only 1/3 of 26M owners on this forum have actual battery spill containment. Oh, I have one of those Lithium Polymer portable 12V starting packs too, but from some previous posts on this forum, I thought that the little hand-held ones too are limited in CCA to the extent that they would not work for starting a DF70A. It would be nice to find out that is not the case. Jeff
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Be Free
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Joined: Fri Nov 23, 2012 6:08 pm
Sailboat: MacGregor 26X
Location: Steinhatchee, FL

Re: 26M - Battery Compartment?

Post by Be Free »

Jeff,

Thanks for the compliment but I don't claim expertise in these areas. I'm just passing on what I've learned from others. I consider a day when I don't learn something new (and hopefully useful) to be a wasted day.

With your batteries coming up on two years they are probably still pretty close to their designed CCA. You can get a battery tester for around $50 that will measure the CCA, MCA, and internal resistance of your batteries (and a bunch of other stuff that you don't care about on a boat). I've found it's better to know when your battery is getting weak rather than finding out one morning it won't start the truck. My tester says that the battery in my old F150 is not likely to make it through the winter.

I have a similar charger but I bought it used and I can't find a manual for it. I'm not sure what the test does before it begins to charge. I suspect it is mostly checking internal resistance. I've not measured any current going into the batteries during that phase. Does anyone know what is actually happening? :?:

If you know that your batteries are not starting batteries then they have to be dual purpose "deep cycle" batteries. Start batteries are designed to give a short burst of high current to the starter. They will be quickly damaged if they are discharged deeply. A single time of completely discharging a start battery can destroy it.

The dual purpose marine-deep cycle batteries are slightly "beefier" start batteries. They are start your engine better than a deep cycle battery and handle house loads better than a start battery. Kind of like a certain power-sailor we all know that sails better than a power boat and powers better than a sail boat. It's a compromise. Like our boats, you have to know their limits. A 20% discharge is probably safe.

A deep cycle battery is usually taller and heavier than either of the other types. It has thicker plates and more electrolyte. That is what allows them to be deeply discharged without damage. It's also why they don't make good start batteries. Thick plates can't deliver the high current quick burst that a starter needs. Start batteries are sprinters; deep cycle batteries are marathoners.

Another clue that your batteries are probably dual purpose is that they have a CCA value on them. Deep cycle batteries seldom (never seen it but I won't say never) list CCA or MCA values. They are just not applicable. They also have more AH capacity; 200+ is normal.

Voltage is not a very good indicator of the state of charge in your batteries. It is better than nothing, but it is not really accurate unless you let the batteries sit for quite a while (24 hours in most cases). Your battery voltage will read lower than it actually is when it is discharging, particularly at high rates. It will read higher than it actually is for quite a while after you stop charging.

LED lighting will cut down on the current considerably; only sailing in the summer even more so. I've been to Alaska a couple of times in the summer and I have actually read a newspaper outside at midnight but I was quite a bit north of where you are.

By the time you have worn out your existing batteries you will have a better idea of what they can put up with and with what you really wish they would do. You may find out that they are exactly what you need. It's what I started out with but I like to stay out for days at a time, I don't have any LED (yet), I sail year-round, and I don't like listening to an engine running. That's why I have something different now.
Bill
2001 26X Simple Interest
Honda BF40D
"If I were in a hurry I would not have bought a sailboat." Me
JeffJuneau
Engineer
Posts: 154
Joined: Mon Jul 20, 2020 11:37 am
Sailboat: MacGregor 26M
Location: Juneau, Alaska 2009 26M 70hp Suzuki

Re: 26M - Battery Compartment?

Post by JeffJuneau »

Apologies for the previous double-post... I didn't see the 2nd page tab, and thought that I had forgot to send my post. My bad...
OverEasy
Admiral
Posts: 2012
Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26M - Battery Compartment?

Post by OverEasy »

Be Free wrote: Sun Jul 25, 2021 9:13 am Jeff,

Thanks for the compliment but I don't claim expertise in these areas. I'm just passing on what I've learned from others. I consider a day when I don't learn something new (and hopefully useful) to be a wasted day.

Ditto!
8) 8) 🐩
JeffJuneau
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Posts: 154
Joined: Mon Jul 20, 2020 11:37 am
Sailboat: MacGregor 26M
Location: Juneau, Alaska 2009 26M 70hp Suzuki

Re: 26M - Battery Compartment?

Post by JeffJuneau »

This as been a very helpful thread for me. Thanks for all the free the education. I need it. Jeff
OverEasy
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Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26M - Battery Compartment?

Post by OverEasy »

We all benefit Jeff Juneau from the dialogs on these forums.
Each participant brings their own constructive knowledge, experience and perspective to these forum dialogs.
We are all better for having the opportunities to bring up topics of interest and curiosity, to hear from others their thoughts as to solutions or encouragement. :) :)

Don’t miss out on the archived forum dialogs.
MacGregor sailors have been at this for awhile and we’ve found many of the old discussions have relevance today.
There have been some truly remarkable individuals contribute their help and knowledge and wisdom over the years.
TrueLy Remarkable.

The projects and modifications are some of the most interesting and inspiring to me.
The Mac series of boats are a baseline canvas upon which sailors from around the world have embraced and modified from day one.
The Macs provide the sturdy canvas upon which desires, needs and personalities can create a truly unique experience.

8) 8) 🐩
JeffJuneau
Engineer
Posts: 154
Joined: Mon Jul 20, 2020 11:37 am
Sailboat: MacGregor 26M
Location: Juneau, Alaska 2009 26M 70hp Suzuki

Re: 26M - Battery Compartment?

Post by JeffJuneau »

Thanks OverEasy, That's good advice. I never push the "start topic" button without a search of my question in the general forum tab. Either, I do not find a answer to my specific question, or my search words didn't draw out the answer I am looking for. In the case of this thread, it was started by someone else. I also check the mods section, but the lack of detail there sometimes leaves me with more questions than answers. Hope I am not over-using the knowledge base in this group, because I already posted another question on the performance discussion section that has me scratching my head, and my forum search on furler rigging and masts didn't address. Appreciate your help, Jeff
OverEasy
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Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26M - Battery Compartment?

Post by OverEasy »

Hi Jeff Juneau!

I recently was reading a couple posting on rigging as that is an aspect I could definitely gain some knowledge on.
Don’t know if it helps (as you may have already found it) by a recent thread at viewtopic.php?f=7&t=28368&p=351083&hili ... ng#p351081 that I found informative.

I would not by any stretch of the imagination presume to be a rigger but I’m trying to learn in preparation as best I can as I go along.

I do know that the furling line likes to have as straight an entry to the spool as can be afforded while also making the unguided length as short as reasonably possible to keep the line from bunching and fouling.

I do know that there is a sequence to adjust the mast stays to get the desired forestay tensioned properly.

I do know that many people have opted for a dual back stay with a gathering tensioner so it can be adjusted as needed while in use.

After that when it gets into fine tuning and proper tensioning values I’m still at something of a loss to be honest.
We’re still very much a newbie on these finer point but they do make a difference in how a boat handles.

Remember, I'm pulling for you. We're all in this together." :D :D

Best Regards,
8) 8) 🐩
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Be Free
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Re: 26M - Battery Compartment?

Post by Be Free »

JeffJuneau wrote: Sun Jul 25, 2021 12:55 pm Apologies for the previous double-post... I didn't see the 2nd page tab, and thought that I had forgot to send my post. My bad...
Getting thanked twice for one answer. That sounds like a "win" to me! :D
Bill
2001 26X Simple Interest
Honda BF40D
"If I were in a hurry I would not have bought a sailboat." Me
Xen
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Sailboat: MacGregor 26M
Location: Florida

Re: 26M - Battery Compartment?

Post by Xen »

Hi, I was delighted to discover this discussion as I'm replacing the FLA batteries in a 26M which I bought recently. Because of the spill containment issue and also the danger of hydrogen outgassing, I decided to replace the FLA batteries with sealed AGM batteries (CTC Nautilus group 24, 79AH each).

I bought a pair of the BWY stainless steel battery straps mentioned by JeffJuneau (Jul 19, 2021 4:15 pm) but I don't know how to install them. Can anyone provide details and/or photos showing how the BWY straps are installed? It looks as if a previous owner might have installed plumber's strapping along the rear wall of the battery compartment using bolts which I guess may have been intended for battery straps. However, the bolts are very short and so are the pieces of plumber's strapping - much too short to go around a battery. I'm thinking of getting some longer bolts and using them to mount the BWY SS battery straps, but I'd welcome suggestions from anyone who is familiar with the BWY straps.

Thanks,
Xen
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dlandersson
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Re: 26M - Battery Compartment?

Post by dlandersson »

Pizza? :)
JeffJuneau wrote: Sun Jul 25, 2021 12:55 pm Apologies for the previous double-post... I didn't see the 2nd page tab, and thought that I had forgot to send my post. My bad...
OverEasy
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Sailboat: MacGregor 26X
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Re: 26M - Battery Compartment?

Post by OverEasy »

Hi Xen!

If I’m not mistaken the SST battery straps you mentioned are designed to wrap around the long side of the battery to clamp the battery to the side wall. I don’t believe they are designed to go over the top.

(Also, a ‘sealed’ battery will still vent hydrogen (and oxygen) when charging.
The ‘seal’ aspect refers to liquid spillage where the battery is tipped or bounced…. Like in a boat)
If the battery didn’t have the capability to vent the gases generated during charging it would inflate like a balloon with an ideal Stoichiometric ratio of gasses, so ‘sealed’ batteries actually still let the gases escape via tiny vents.)

On Over Easy (a Mac26X) the factory battery compartment is under the aft galley seat.
Not a whole lotta room there to mount dual batteries end-to-end fore-to-aft to enable using those type of SST straps.
That’s why we made a fiberglassed supported sub-structure and then secured a Trex deck to the new support AND the companionway side wall of the galley. A toe rail was added to the Trex decking to keep the battery containment boxes from shifting side-to-side & fore-aft.
An appropriate battery acid resistant non conductive web belt (made to hold down batteries) was then looped up and over the batteries in their containment boxes to hold everything rigidly in place.

Wish I could have taken pictures but the space was to small and awkward to get any photos that made sense.

(This was BEFORE we added the Air Conditioner (A/C) unit which needed to be on the same side of the boat. :? :( This additional weight means we have to pay additional attention to how we load the boat to maintain an even balance. :| So we will either move the A/C, move the dual batteries, add additional batteries &/or add additional static features such as fresh & grey water holding tanks to the OPPOSITE side. No good thing goes unpunished! :D :D )

The flexible battery hold down idea might be of some interest to you to help facilitate your installation.

Best Regards,
Over Easy 😎😎🐩🐈
JeffJuneau
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Posts: 154
Joined: Mon Jul 20, 2020 11:37 am
Sailboat: MacGregor 26M
Location: Juneau, Alaska 2009 26M 70hp Suzuki

Re: 26M - Battery Compartment?

Post by JeffJuneau »

Hey Zen, I just wanted to confirm that OverEasy was right on in his description of how the BWY stainless straps restrain the two batteries in my 26M. My 26M has three holes drilled in the aft fiberglass shell right behind the battery box. Three long hex-head cap screws are used to hold two of the straps against the two batteries. It is very secure, and I think they wouldn't move if the boat was turned upside down. I have to confess that I haven't installed. d the battery boxes that I thought I would by now. Too busy rebeding deck fittings and installing a Wallas 1300 heater.

I was intrigued by your solution of just using sealed AGM batteries to get around the battery box challenge. The two AGM batteries you listed tlook like they would cost less than than the cost of my time to fabricate a fiberglass box. I have a related question. Would using using an AGM battery like yours supplant the need to have batteries contained in a box? If I want to get my electrical system certified as ABYC compliant or if the US coast guard inspects my electrical system, would I be able to pass if I have uncontained (but properly secured) AGM batteries like yours?
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