I need to replace my starter battery and want as many cranking amps as can fit in a group 24 battery. I saw this marine starting battery with 1000 cranking amps for a good price. Is it advisable to get a DP battery for the starting bank instead? We’re just island hopping in the Salish Sea, and I don’t anticipate using it for anything but starting. We have a very substantial house bank.
Group 24 starter battery
- Thread starter skunther
- Start date
Forget buying a "start" battery. Get a Group 24 marine deep cycle there will be plenty of cranking power to start the diesel and it will have more capacity to serve as a back up battery.
What is a Deep Cycle Battery? - Marine How To
Light Cycle vs. Deeper Cycle NOTE: This article deals with FLOODED marine batteries, not AGM or GEL batteries. The Problem: The problem, as I see it, is one of dishonest marketing where multiple battery types wear the same clothes (sticker) and will perform differently when
marinehowto.com
If you need 1000 CA, then yea, that's fine. If you don't need 1000 CA, a DP battery or even a deep cycle if it has sufficient CA will be a little more durable and might last longer, but the difference might be small. All three types have roughly the same capacity, it's just that a starter type can provide more instantaneous power. You might be able to save $10 on a better name brand at Sams Club or other places.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,913
Next time you get to Seattle stop at
Dyno Batteries
4248 23rd Ave W, Seattle, WA 98199
I find the product to be excellent. My house bank is two of their 30tmx batteries. They fit in a group 27 sized battery box.
This one has given me the most bang for the buck.
Dyno Battery - Premium Quality Battery Manufacturing - Made in the USA
65 lbs. 12 volts 135 Amp Hrs approximately $160-$175 a batttery. Pick up at the warehouse in Seattle
Dyno Batteries
4248 23rd Ave W, Seattle, WA 98199
I find the product to be excellent. My house bank is two of their 30tmx batteries. They fit in a group 27 sized battery box.
This one has given me the most bang for the buck.
Dyno Battery - Premium Quality Battery Manufacturing - Made in the USA
65 lbs. 12 volts 135 Amp Hrs approximately $160-$175 a batttery. Pick up at the warehouse in Seattle
Dyno has a good reputation, even here on the right coast. Their website is a little short on construction details. I wonder how they get 135ah out of a 65 lbs battery, that's about the weight of a standard 70 ah battery. Generally the heavier the battery the more ah you get.
CCA and group size are directly related. Why do you need 1000 CCA? My 3JH3 starts easily with a group 24 and a 1.2kw Starter (100 Amp draw for a second).
Presume you have a 27 hp yanmar? A group 24 (70Ah) is probably more than enough.
More important than size is installation, lack of corrosion on connectors, the correct type (AGM if venting of fumes is a concern), etc...
A dedicated starter battery will last much longer as a starter battery than a hybrid battery will when used in a starting role. The plate. The last one on my boat was 10 years old. I replaced it as a precaution but it was still running strong. That being said, most batteries don't die, they are killed by their owners.
Presume you have a 27 hp yanmar? A group 24 (70Ah) is probably more than enough.
More important than size is installation, lack of corrosion on connectors, the correct type (AGM if venting of fumes is a concern), etc...
A dedicated starter battery will last much longer as a starter battery than a hybrid battery will when used in a starting role. The plate. The last one on my boat was 10 years old. I replaced it as a precaution but it was still running strong. That being said, most batteries don't die, they are killed by their owners.
My engine is hard starting, but started much easier when I attached a 1000 amp jump starter. I’m looking for a stronger starting battery.
I didn’t know a dual purpose would die quicker if used as a starter.
I didn’t know a dual purpose would die quicker if used as a starter.
Why is it hard staring? The bigger battery may mask a bigger problem... hard starting means more current, more heat in wires, more wear on starter, etc...
This is the question. What are the symptoms?
If the engine is turning over too slowly, then the existing battery may be past its prime, how old is the battery? Or, the connections have become corroded or loose, reducing the power actually getting to the starter. Or, the starter is starting to fail with brushes going bad. Or if you have a Yanmar, you could have the known Yanmar wiring harness issue.
Check the wiring to the battery and also the starting circuit, it may be the cure. For a factual and real world examination and the perceived need for a large starting battery I strongly recommend going to the marine how to website. It's a no bull explanation of start battery requirements from a marine electrician who knows his stuff and shares freely. Rumour has it he wired Noah's arc such is his expertise. Again try to solve the problem not mask it. Your boat your choice.
Have you taken into account the size of the cable running to the starter motor? Manufacturers chronically undersized these.
What size cabling do you have going to the starter? It might be that going up a few sizes will make that engine crank with authority.
dlochner and east coaster provided a very informative site in their comments above. Here's an excerpt from that MarineHowTo page: "Starting batteries should not be used for deep cycling, but deep cycle batteries can easily be used for most starting purposes." This would apply to hybrid batteries as well.
I recently shopped for a new starting battery and considered the so-called "deep cycle" Super Start 24DCM battery. As far as I can tell, it is a rebranded Deka (East Penn) Marine Master DC24. These are standard flooded lead acid batteries, the same as the Super Start 24MSJ referenced in post 1. However, if used strictly as a starting battery, you might also consider the Super Start 24MS (Deka Marine Master 24M7) which is a maintenance-free battery (calcium chemistry, presumably), so you wouldn't need to worry as much about topping off with water.
I focused on O'Reilly since that was indicated in post 1, but the box stores (Sam's Club, Costco, Walmart, etc) all offer essentially similar battery options for a better price.
Thanks for all that. I will review the links provided. Long story short, after some work done in the engine last fall, it has been hard starting. The starter sounds the same as it did before the work was done. I really don’t think that anything electrical is the issue, only that there is some mysterious issue with the engine which prevents it from starting properly now, though it runs fine once started. The shop has been unable to identify the problem. I have run it hard per other posts and that may have reseated seals (but if they weren’t seated before the work was done then why did it start well before?) Regardless, I am not seeking any answer to these questions as I have posted extensively on them in other posts. I have exhausted what I’m willing to deal with on that for now and will revisit it in the fall, but in the interim, for the purposes of this post, I need the engine to start, that is why I am looking for an appropriate higher app battery to get us through the season.
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jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,913
Sure makes sense. I am at my boat or a couple days. Pleased that it started on the second attempt. This is an improvement over the hard starting that occurred shortly after the rebuild install. Like you I took the boat out in the sound for a run/sea trial. I ran it WOT for 30 minutes. Did a number of surge changes in RPM once the temp was up. Temps moved up into the 175 range. Granted I have a different engine. Since that exercise the engine starts on the second try.
The freshly charged batteries do make the starter wind up quickly. That is a help in firing off the engine.
The freshly charged batteries do make the starter wind up quickly. That is a help in firing off the engine.
Aside from doing some other "work" on the engine, it's normal for the starter motor to need a rebuild after about 1000 or 1400 hours. From your symptoms perhaps the starter was not addressed.
This rebuild is usually inexpensive (by boat expense standards...). Find a shop that does a lot of marine starter/alternator work.
The decline in spin from the starter is gradual and often goes unnoticed, until that motor gets a refurb. As a friend of mine put it, after having this same work done, it now starts "like its hair is on fire!" When I did that preventative maintenance job on the starter on our prior engine the result was almost startling. Best hundred dollars I had spent on the boat... !
As for batteries, the advice from "MarineHowTo" regarding starting our small diesels is spot on.
Good luck on trouble shooting.
As Red Green used to say: Keep your stick on the ice and we're all pulling for ya!
This rebuild is usually inexpensive (by boat expense standards...). Find a shop that does a lot of marine starter/alternator work.
The decline in spin from the starter is gradual and often goes unnoticed, until that motor gets a refurb. As a friend of mine put it, after having this same work done, it now starts "like its hair is on fire!" When I did that preventative maintenance job on the starter on our prior engine the result was almost startling. Best hundred dollars I had spent on the boat... !
As for batteries, the advice from "MarineHowTo" regarding starting our small diesels is spot on.
Good luck on trouble shooting.
As Red Green used to say: Keep your stick on the ice and we're all pulling for ya!
Roger that. I will add it to the list for the fall and hope that helps as well. In the meantime, regarding a starting battery for the short term, is there any reason I should not pick up this battery with 1000 cranking amps?
I need a new battery anyway, so it’s a necessary expense regardless.
One thing - I do have my windlass connected to the starter battery. It seems that could draw a dedicated starter battery down enough to damage it, no? In which case, would it make more sense to pick up a dual purpose?
How much can a starter battery such as the one I indicated above be discharged before doing damage? I see conflicting information on this.
One thing - I do have my windlass connected to the starter battery. It seems that could draw a dedicated starter battery down enough to damage it, no? In which case, would it make more sense to pick up a dual purpose?
How much can a starter battery such as the one I indicated above be discharged before doing damage? I see conflicting information on this.