#1 and #2 Batteries
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Bill Prange
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Mar 17, 2021, 7:16:39 PM
My #1 and #2 batteries have been West Marine’s "Dual Purpose " marine batteries. My #2 battery is old and failing and I’m considering moving the other Dual Purpose to #2 and install a dedicated deep cycle Starting Battery as #1.
I’m hearing mixed opinions about retaining 2 Dual Purpose vs. 1 Dual Purpose and 1 dedicated starting battery and would appreciate any educated opinions.
Thanks,
Bill Prange
“Hawkeye” NS 26U #233
Richmond Yacht Club
San Francisco Bay
Elizabeth Powers
Mar 17, 2021, 8:11:00 PM
Hi Bill,
I suggest you ditch the dual purpose batteries and just go with deep cycle. We have done so since 2008 . The deep cycle is more than able to start the engine and will last much longer. If you only have 2 batteries you may wish to alternate from #1 on odd days to #2 on even days. Both then get cycled regularly. We now have a house bank of 2 100 amp hour batteries and a single 100 amp hour deep cycle that is really a back up battery. This way we do not run the house bank below 60%.
this means if we use 80 amp hours we still have 120 amp hours in the bank. With a single 100 amp hour battery if we used 80 amp hours the battery would be reduced to 20 amp hours, or 20%. It will greatly reduce the life of the battery.
I also suggest you upgrade the battery cables to reduce voltage drop. Replace all the contacts.
The original cable size was smaller than I think it should be and was probably welding cable not marine grade.
There is good information on a sight called Mainesailhowto.com and also at sailboat owners.com if you search for electric 101 or batteries.
R C Collins is a truster contributor to that site.
Rob Powers
Respite 26C #50
Sidney BC
Mar 17, 2021, 11:14:05 PM
Bill,
I have just installed two Mastervolt AGM group 31 batteries in place of the West Marine dual purpose that came with the boat. I’ve used these batteries in the last several boats, and have had excellent performance from them. I will use them in tandem so as to not put more cycles on either. For not much money you can carry a lithium powered jumper in case you should should need a boost. I’ve always had a solar panel so they are kept up to full charge when the boat is idle.
Ron Weber
N22 Magic Time
Punta Gorda Fl
Richard Lane
Mar 18, 2021, 2:47:44 PM
Where and how to best connect an emergency start jumper?
Richard Lane
NS26c #35 Swoose
Port Townsend
Bill Prange
Mar 18, 2021, 4:10:25 PM
Thanks, so far there is a shared opinion to carry 2 deep cycle starting batteries, although the previous owner of my boat swears by carrying 2 multipurpose batteries. There is a difference of opinion regarding having the 2 batteries in tandem or not. So far, I turn the battery switch to “Both” when I’m starting with a tired #1, otherwise I use #1 as my dedicated starting battery and use #2 for cabin power when anchored or berthed.
I like the advice to carry a lithium jumper for emergencies, as well as having a solar panel to charge the batteries when off shore.
Thanks,
Bill Prange
“Hawkeye” NS 26U #233
Richmond Yacht Club
San Francisco Bay
Joe Valinoti
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Mar 18, 2021, 4:51:43 PM
Richard: I assume that with your current two battery system, you don’t have a normal (OFF) - (1) – (BOTH) – (2) SWITCH and just an “ON” switch??
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
Tom Schoenhofer 26C#28 North Star Penetanguishene
Mar 18, 2021, 5:38:56 PM
Hi Dick
That’s a good question.
I have a Duracell lithium emergency start battery, $99 from CrappyTire, about the size of a large pack of cigarettes. I don’t recommend this type because the case is not waterproof and it is too small to start something big on its own, but there are lots of other better options now. It has a removable 2 foot long cable with big clamps like starter cables. It will start my W13 with all batteries disconnected with little trouble. But before I replaced the long (7’?) positive cable which runs red switch to starter motor (there is no ground at the switch so I still have to take the engine cover off and ground to the block) I had to connect the lithium battery + to the bolt on the starting motor. Now with new cable it will just barely start the motor when connected to the red switch with batteries disconnected.
The little lithium battery works much better with a battery in parallel as long as that battery is not totally dead. In this case you leave it for 30 seconds and the little battery charges the dead one enough so it can give a current boost to the little lithium battery. Good for bigger engines.
A totally dead battery looks like a short, the lithium battery has protection built in and will shut off. This means it won’t start a car with a dead, very dead, battery (unless you disconnect the battery of course) but it is easy to turn the red switch off and disconnect on the boat.
I never had to use it on my own boat in an emergency so far but have started a powerboat that ran their battery down partying at the beach. It also charges a cell phone in record time. I think these are a good item to have in an emergency.
I’m a fan of the Everstart deep cycle RV batteries previously sold at Walmart. They work well as start batteries. The label is different but the plastic case appears identical to deep cycle batteries sold at Canadian Tire and others so they likely come from the same plant. My old one is +10 years old and appears to work just as well as the identical one year old. Alas, it appears Walmart doesn’t sell these anymore and have gone to a different supplier.
Before you invest in batteries, replace your lights with LEDs. It made a big difference.
Tom
26C #28 W13
Penetang
Mariner’s Cat V 26C Brentwood Bay BC
Mar 18, 2021, 5:49:11 PM
I have a pair of Trojan golf cart batteries as a house bank and a Deka dual purpose for a start battery. Both banks are managed by a Blue Sea combiner.
I set the battery switch to house and let the combiner figure it out. No messing with it.
Richard Lane
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Mar 18, 2021, 11:41:01 PM
Joe, I do have the usual 4 way selector switch mounted by the holding tank, but the back of the switch looks to be “very busy” and the cable run to the starter pretty long.
Dick Lane
NS26c #35 Swoose
Port Townsend.
Joe Valinoti
Mar 19, 2021, 8:40:55 AM
Richard: I suspect I read your post incorrectly.
329a...@gmail.com
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Mar 31, 2021, 10:14:44 AM
My two cents, in the 35 years that I’ve owned Aloki I have always had number 1 as a start battery and number 2 as a house battery system. The concept of alternating battery one and two on odd versus even days is an old Caribbean chartering protocol. Not appropriately suited for privately owned yachts in my opinion
My start battery is a high cranking 12 V battery (which I replace every five years) and the house system is a series of deep cycle batteries designed to handle the amperage requirements of the boat including refrigeration. (Last set of house batteries lasted close to 10 years) I find that running the engine in and out of a harbor on a daily basis is sufficient to keep the battery systems charged while we’re cruising.
In addition I have found it very useful over the years to have an amp gauge mounted in lieu of the original 12 Volt meter in the fuse panel. This way you can monitor how much your alternator is putting out in amperage and thus deduce the state of the batteries.
Use use or disregard comments at your convenience. Cheers Gary
Gary Forster
NS 30329 / Aloki
r
Question;…
Advice needed
Both of my batteries are on shore power as normal in the slip, however…only one of them is charged by the westerbek alternator when under way, Being that I just bought this boat , is this normal, Both batteries seam to be the same?..No difference via the above comments.
2nd Question;
My current water pump is a SHURFlo Model # 225-3000, 12 volt, 7.9 amp, 11.4 GPM, Open flow 3.0, That needs replacing,very old not working, don’t want to try a replacement kit, As I am not going to use the shower system, do I really need 11.4 GPM. ??? A number of the SHURFlo water pumps are a lot cheaper at 3.5 GMP, do you recommend any other make, would the 3.5 GPM or less work for just the gally and head faucets ?
Thanks
Ron B
NS 26
Buona Vita
Joe Valinoti
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Mar 31, 2021, 2:12:21 PM
Ron: The engine normally charges the batteries you have the battery switch turned to. Also, if you leave your boat plugged in and battery charger on in your slip all the time, you will not know if you have battery problems until some morning when you wake up with dead batteries at anchorage.
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
From: r
Sent: Wednesday, March 31, 2021 1:46 PM
Subject: Re: #1 and #2 Batteries
r
Mar 31, 2021, 2:20:17 PM
Hi Joe;
The battery charger is a trickle charger so it only charges when the battery falls below a certain voltage, Not full charge all the time and I normally leave it on Both.
Any advice on the water pump ?
Ron B
NS26
Buona Vita
Bob Neches (Solar Wind, N26C #143)
Mar 31, 2021, 2:52:41 PM
Ron,
Responding to your second question, you definitely do not need an 11.4 GPM pump on the boat anywhere other than a bilge pump. That volume could empty a water tank in five minutes.
People going on long trips without opportunity for refilling go for less, but 3-4 GPM should be more than adequate. (I forgot to tell my mother about water conservation when I took her on a Caribbean charter once, and she emptied the boat’s water supply in one shower even with pumps at that volume.)
You’ll probably get a lot of opinions about pumps. I tend to just go with best price among the competing pumps that meet my spec. Pretty much all the major manufacturers have pleased me one time and disappointed me another.
– Bob
Solar Wind
Nonsuch 26C #143
r
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Mar 31, 2021, 3:35:30 PM
.com
Thanks Bob;
I didn’t think I needed that GPH flow, ??? why so much, located in the head lower cabinet, I agree 3.5 should be quite enough, Prior owner had shower stuff in the head,prob wanted high pressure when taking a shower…
Thanks again, for the advice
Ron B
Buona Vita NS 26
Joe Valinoti
Mar 31, 2021, 6:27:26 PM
The point about the batteries is they’ll stay charged. But if you have a bad battery or batteries, it won’t show up. I doubt if the price difference is much and would install the same size or spec’d pump
Group/CAGBz1cnX5h%3D2FLw4TtnNaFBph_LhdWdpf_JXMPXDDZawu2tgTQ%40mail.gmail.com?utm_medium=email&utm_source=footer).
Bill Prange
Mar 31, 2021, 10:12:41 PM
I had a marine electrician update my charging system two years ago so that both batteries are charged on shore power as well as by the alternator. My #1 is charged first and then #2, at least that is my understanding. It’s made a world of difference.
Bill Prange
“Hawkeye” NS 26U #233
Richmond Yacht Club
San Francisco Bay