Yee Haw No More 8Ds on ASD!!

[ranger58sb]

Still, a wet 8D is hard to beat for dumping big amperage into things like starters and thrusters.

But a pair -- or sometimes three -- G31s can provide as much as or more cranking amps than some single 8Ds. Certainly enough to start most engines, I'd guess enough for thrusters given installers often use a pair of Odyssey G31s.

For an extreme example, a pair of PC2150s would give 2300 CCA, 2740 MCA... and each individual battery is much easier to schlep than would be a single 8D.

-Chris

 

[motion30]

3 golf cart batteries will fit in the place of one 8d. And are much better suited for a house bank.

 

[catalinajack]

There seems to be an assumption by many boaters that there must be dedicated starting batteries apart from the house bank. Why, I do not understand. My boat has a house bank of eight golf car batteries that also start the two Lehman 120s quite easily. We do have two generators aboard that have dedicated starting batteries. If, in the unlikely event, the house bank becomes so depleted that it cannot start the engines, the generators can be started to recharge the house bank or jumper cables can be used to start the Lehmans. I once started the Lehmans (easily) with those golf car batteries unintentionally depleted to 20%.

So, it seems to me that a much simpler and space-saving arrangment can be had doing as I do. No doubt there are those who feel more comfortable having separate starting batteries, why I don't understand but, as we all know, there are opnions and there are opinions. Which is the better arrangement is just an opinion, mine included.

 

[motion30]

I agree. My 3208 cat start easily and my twelve Trojan t105 hardly notice

 

[rslifkin]

There seems to be an assumption by many boaters that there must be dedicated starting batteries apart from the house bank.

In my mind, from a safety and idiot-proofing perspective, there should be some source of starting power separate from house power just in case. I also don't love cranking engines off a house bank unless it's massive, as some electronics can be fussy about the sudden voltage dip during cranking. But in a lot of cases, a twin engine boat can safely share start batteries between 2 engines, etc. There's no reason for each item to have its own battery.

In my case, my engines don't need a ton of cranking power, so they each have a single G27 as a starting battery. Generator shares with the stbd engine normally. So there are 2x single batteries plus the house bank on board, not too bad overall for space, complexity and number of batteries.

 

[Alaskan Sea-Duction]

Star Weird

Hey there ASD!!! I am one of the other Camargue's here in the PNW.

Hey Scott! Last September we were tied up to Miller and Miller right above the locks We watched you doing the "Lock Dance" waiting for the lock. Saw you coming back in. Tried to get you on the VHF. Glad to see another Camargue.

I have my house batteries in the same place, but I have battery boxes.

 

[ghost]

Along this vane, I would like to add house bank capacity but, I have twin Cat 3208s that need lots of cranking power. I have 4 8Ds. Two for starters, two for house. The problem seems to be my two refrigerators. One draws 6.5amps at 110v. 6v golf carts don't seem to have the crank power. Lithium does not seem to have it. The way I'm set up: Port start 8D is isolated. Stb 8D is included in the house bank. One 16kW generator starts from the stb 8D, the 4kW one has its own start batt. I have a combiner (not working). I sure would like to add capacity without adding more battery boxes as the position of my Racors prevent that currently. Any suggestions?

I use to have two 8ds, one for each 3208. About 5 years ago I replaced the two 8ds with a single group 27. Used the excess room to expand the house bank. 3208’s start right up, they don’t need 8d.

 

[seadancer]

Thank you, "ghost." I got a good deal on a couple of used ones, so hope not to have to deal with battery replacement for a while, just keeping them watered.

 

[Arc]

I am very interested in how you added an automatic watering system for your batteries. I have for of them on a "smart charger" but they suck up a lot of water. Was it a system you bought, or something you invented? Thank you for any information.
Patty
Sea Dancer

https://www.batterywatering.com/

The system seems to work as stated. It was simple to set up for both batteries. I think I paid about $150.00 for duel 8d plus the filling pump.

 

[MurrayM]

In my mind, from a safety and idiot-proofing perspective, there should be some source of starting power separate from house power just in case...

NOCO Genius Boost GB70: https://www.amazon.ca/NOCO-GB70-UltraSafe-Lithium-Starter/dp/B016UG6PWE

 

[rslifkin]

NOCO Genius Boost GB70: https://www.amazon.ca/NOCO-GB70-UltraSafe-Lithium-Starter/dp/B016UG6PWE

Based on experience, I can say that even a good size jump pack is unlikely to start a decent size engine if you've got it hooked to a reasonable size bank of dead batteries. The drained batteries will sink enough current that there still won't be enough to get an engine going. So it'll work if things are just barely too low for a start, but I wouldn't count on it as an alternative to paralleling another bank of batteries or switching the engine to another bank entirely for startup.

 

[squimmy27]

I may be missing something, but it seems that the pro/cons in general on the battery options revolve around price/weight. My spreadsheet to replace my 4 8Ds looks like (relatively speaking):
G31 Lithiums/100 AH, 8 @ $900 per = $7,200
G31 Oasis/110 AH 8 @ $512 per = $4,096
G31 Odyssey PC2150 8 @ $440 per = $3,520
Duracell/Interstate/whatever 8D/245 AH 4 @ $300 = $1,200

My energy spreadsheet which isn't totally complete, is about 700/day, big hitter is the marine freezer. I'm I reading the posts correctly? What I haven't captured is life of batteries...given my real 'age' (as opposed to how old I feel ;=), I'm optimistically projecting 15 years. If the options are oranges-2-oranges, I can deal with hiring a couple of hefty young men to replace the 8Ds twice in the coming years. But are there safety, reliability, etc. issues that I'm not taking into account? Maintenance is trivial IMO (keeping water topped off, batteries connectors clean, etc.)

 

[Beaverlake]

We have dual 330hp Cummins 6bta plus an 8kw Onan. Previous owner had Magnasine set wrong, fried four Full River 6L AGMs. Had 2x 8d starters on 20 year old crappy charger and fried those as well. Replaced 8ds with Grp31 AGMs and new smart charger. Replaced 6L AGMs with 8 x Costco Interstate 6v plus Battery Watering Technologies set up. Reset inverter charger to proper settings. Battery watering system makes top off a non event. Water usage during and after about 150 hours of use over a lot of cruising has been negligible. At about $105 each for the batteries plus new boxes plus watering kit plus new cable and associated tools I’m all in at about $1,200. The engines have plenty of starting power and we have 840Ah total on the house see (420Ah usable @ 50% discharge). I’m totally satisfied with both performance and price so far.

 

[ranger58sb]

I may be missing something, but it seems that the pro/cons in general on the battery options revolve around price/weight. My spreadsheet to replace my 4 8Ds looks like (relatively speaking):
G31 Lithiums/100 AH, 8 @ $900 per = $7,200
G31 Oasis/110 AH 8 @ $512 per = $4,096
G31 Odyssey PC2150 8 @ $440 per = $3,520
Duracell/Interstate/whatever 8D/245 AH 4 @ $300 = $1,200

My energy spreadsheet which isn't totally complete, is about 700/day, big hitter is the marine freezer. I'm I reading the posts correctly? What I haven't captured is life of batteries...given my real 'age' (as opposed to how old I feel ;=), I'm optimistically projecting 15 years. If the options are oranges-2-oranges, I can deal with hiring a couple of hefty young men to replace the 8Ds twice in the coming years. But are there safety, reliability, etc. issues that I'm not taking into account? Maintenance is trivial IMO (keeping water topped off, batteries connectors clean, etc.)

Latest initial capacity figure I've seen for Firefly Oasis is 116 Ah. Odyssey's PC2150s are spec'd at 100 Ah.

You might add Lifeline GPL-31XTs to your list (125 Ah each), as well as Lifeline's 6V GPL-4CTs (220 Ah/pair). Latter may fit in only slightly larger space the G31s, and could increase your initial capacity significantly.

I don't think I'd expect 15 years from AGMs; we got 12 years from one bank of Odysseys... almost always able to recharge to 100% after a cycle... but I'm not sure what our ending capacity was at that point. Makers usually figure 80% is end of life, not sure where we were.

The other Odyssey bank is at about 10 years just now, and it's the one with the larger fridge on it... so I'm making plans to replace next year if necessary.

VRLA AGMs (and gels) don't off-gas as much as might flooded wet cells, in case that's an important safety issue for you.

-Chris