Batteries - Express 305

PDX-Boats

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Anyone had to replace the batteries in an Express 305?
The battery supporting my port engine appears to be bad. It wont' charge and requires me to run the batteries in parallel in order to start the engine.
My boat has a generator in front of the batteries so it looks like it is going to be challenge to replace them.
I'm planning to probably just replace them all at once. I suspect it's better for the batteries, safety and hassle factor.

Any thoughts or suggestions on replacement would be appreciated?
Tips, tricks, recommended battery brand/model?
 

Fishtales

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There is a lot on this site on the topic. As it is the same hull is mine and probably likely equipped some info:
- GW recommends starting batteries for all (4). Assume there are (2) banks with (2) batteries per bank.
- GW recommends one battery switch be set to (1) and the other to (2). This means one battery bank per engine. Don't use both normally, ok if you need to to start.
- Group 27 batteries.
- All batteries are made and branded by only a few manufacturers. So brand may not matter much.
- I used Duracell last time from a local Battery and Bulbs store. They had a sale, it was handy. Don't forget the core charge/swap. Used Deka in the past.
- If there is a brand you can get a deal on, work to find out who makes the battery. Prob like the rest.
 
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drbatts

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Hope you have strong arms and are somewhat flexible. I replaced my batteries at the beginning of last season. Since you are replacing all of them, the easiest way is to start on the port side and one by one pull them out. With the generator being in the way, you almost have to keep sliding them over to the port side and pull them out one by one. You kind of have to crawl over the generator to unhook and re-hook them. there is not a lot of room in there, so a smaller 1/4 socket wrench will work a little easier for this. If you want to put in underwater lights or run any wires to the transom, now is the time as you will have great access with the batteries out.
As far as batteries go, I went with west marine as they were on sale at the time and offered a boat club discount. In my experience, brand hasn't mattered so much as they all tend to have the same life expectancy. As far as size goes, look to see what you have in there now and keep in mind Yamaha engines require a very high RC.
 

seasick

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Anyone had to replace the batteries in an Express 305?
The battery supporting my port engine appears to be bad. It wont' charge and requires me to run the batteries in parallel in order to start the engine.
My boat has a generator in front of the batteries so it looks like it is going to be challenge to replace them.
I'm planning to probably just replace them all at once. I suspect it's better for the batteries, safety and hassle factor.

Any thoughts or suggestions on replacement would be appreciated?
Tips, tricks, recommended battery brand/model?

How old are the batteries but more importantly, how do you know the battery won't charge? Yes it may be bad but it also may not be getting a charge. The easiest way to check simply is to use a battery charger and see if the battery does take a charge. If the problem with starting got worse over time, the battery is probably shot but if it happened all of a sudden, it may not be the battery.
 

PDX-Boats

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How old are the batteries but more importantly, how do you know the battery won't charge? Yes it may be bad but it also may not be getting a charge. The easiest way to check simply is to use a battery charger and see if the battery does take a charge. If the problem with starting got worse over time, the battery is probably shot but if it happened all of a sudden, it may not be the battery.
The boat is new to me so I don't know the history. Might just be good to replace them as a known good starting point, but you raise a good point. Couldn't hurt to put it on a dedicated charger for a day.
I would have thought that the onboard changer would have handled it but I have another I can try for good measure
 

teaklejr

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Just pulled 2 of mine out of our 305 last weekend just to charge them up, found out one was bad. Would not take a charge so now I am Just going to replace them all. It’s not that bad getting them out I did take the sound shield off generator to get a little More room.
 
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Fishtales

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Usually I change in pairs (by bank). I've had one bank go before another and vice versa. No need to do all (4) if two are ok. May be better that way versus one big bill.
 
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Hookup1

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You should consider the Duracell AGM's from Sam's Club.

Group 34 43.10 lbs. 955 MCA 55 AH. $119.32
Group 24 52.40 lbs. 800 MCA 78 AH. Did not see availability at my store.
Group 27 61.55 lbs. 900 MCA 92 AH. $158.88
Group 31 67.35 lbs. 1,000 MCA 105 AH. $179.74

I used a Group 34M Duracell Marine AGM for my Yamaha F150's. About 9 lbs lighter than a Group 24 and 17 lbs lighter than a Group 27 with higher MCA rating but less capacity.

For the house I use a single Group 27 AGM. You could parallel two new ones. Or do a Group 31.
 
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Fishtales

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Just measure the size of your mounts. You may find that some of the larger group batteries won't fit. It is a tight space down there, so make sure you measure the current ones and ensure the new ones will work.
 
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efx

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I would also check your charger. Check each bank and each wire set. It’s the first thing I change on any boat. I’m a big fan of Minn Kota digital precision 4 bank chargers.