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whaler

Starting battery or dual purpose starting / deep cycle

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Need to replace my batteries. VP manual says NOT to use deep cycle batteries on EFI as it will cause problems with EFI engines. Previous owner had replaced original batteries with dual purpose Starting /Deep Cycle batteries and things seem to be ok. Is this something I should be concerned about or just go ahead with new dual purpose batteries. Any and all information greatly appreciated.

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As a important fact about " Brand New Batteries ".  There ARE Probably NONE Produced.  The recycling programs have done a lot to reduce brand new lead in batteries.

There is NO reliable full charge voltage or cranking voltages for consumer batteries. There is NO SELL BY DATE.

In short.  Get LUCKY.  Deep cycle batteries can & are being used in starting motor applications............... If you get a good one.

The more important question is.............. What idiot companies are selling problem causing EFI systems ?

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Trust the manual, not the previous owner. Starting battery only for the engine. Deep Cycle for the house. 

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I have 2 Interstate Starting batteries. Season 13 

Had them load tested this spring they both were at 75% 12.7 volts. The Interstate guy was impressed, said go ahead use them for another season. Come back next year.

 

 

:boating:

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Depends on primary application. If they are going to be used as the primary starting battery(s), then a cranking battery is best. If one is say on bank 2 (of a single engine setup) and will be used mostly for a house battery, then a deep-cycle is best. If needed, a deep-cycle can crank and engine, as a backup. 

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A most important factor is if you have to crank a lot to get the engine running.  THAT ENGINE will kill a starting battery very quickly. Every time. Every brand. If  you refuse to correct the long cranking problem ?  A  oversized deep cycle battery will last for years.

Some SPECIFIC computers / ECM are garbage & will not tolerate very  hot or cold batteries. AS batteries get hotter or colder than about 70 F their capacity drops and their voltage drops.

Add those 2 sentences together on 1 engine ?  Only a OVERSIZED deep cycle will be satisfactory.  

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Yup, it all depends ... the VP manual also states 650CCA minimum for EFI engines. Let's keep in mind that these specs were formulated some twenty years ago, and the battery technology has changed dramatically since.

To play safe go with starting flooded battery of 700CCA minimum for the engine, and deep cycle battery or batteries for the house. Another alternative is to go with good 1000ACC or better deep cycle batteries, dual purpose and AGM type possibly, and it will work as it did for the previous owner. With today's choices of battery types and capacity there are valid options that were not available a decade or two ago. Just go with good brand batteries with extra capacity and do not worry. Try not mixing battery types, flooded and AGM for example, as the charger can only be set to one type on all charging circuits.

BTW, I have replaced dedicated starting battery and two deep cycle batteries with three 1150CCA AGM deep cycle batteries five seasons ago and this setup still works for me. The preseason test a few weeks ago after my boat was taken from storage showed my engine battery still at 12.82Vdc and 1168CCA. All of them were and are still above specs even after 6 months in storage.

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Thanks Rich for real life Deep Cycle life spans. Winter storage can cripple a Starting Battery with Lead Sulphation.

All of us. Please go to a great web site & read about ALL types of batteries. You will never have any doubts about what battery to buy again. How to make any battery last at least 200 years.

www.batteryuniversity.com    see BU-804b section  about a battery sulphation prevention plan. 

The search box is in the top right of the main page. Blue in color.

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I run a pair of AGM dual purpose batteries--a group 24 that predominantly does starting duty and a group 27 that is mostly used on the hook.  They've performed flawlessly for the past 2 years, but also spend most of their time on a very high quality charger/maintainer when we're not out on the water.

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Bingo sburke91.  On putting a battery on charge as soon as possible after docking. A smart recharger unit does wonders to a batteries life all year long.  But acid batteries STILL NEED WATER LEVELS CHECKED & REFILLED AS NEEDED.  NO OVERFILLING !!   Added only after a full recharge. When a long recharge can cause some warm & expanded bubbling to push out acid.  This water level is a very tricky part to learn correctly.  

A fantastic charger can reduce the water level problem greatly.

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On ‎6‎/‎23‎/‎2018 at 2:43 PM, whaler said:

Need to replace my batteries. VP manual says NOT to use deep cycle batteries on EFI as it will cause problems with EFI engines. Previous owner had replaced original batteries with dual purpose Starting /Deep Cycle batteries and things seem to be ok. Is this something I should be concerned about or just go ahead with new dual purpose batteries. Any and all information greatly appreciated.

Dual purpose pretty much means it does both functions, so it's not like you're not putting a starting battery for the engine by using a dual-purpose battery; you are, hence why it was fine for the previous owner.

I had a starting battery and 2 deep-cycle house batteries and I just replaced them all with 3, group 31 dual-purpose batteries. 

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Thanks to all for replies. Going to go with the same batteries former owner had installed. Talked with him this morning and he had no issues . 

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