Need help deciding on a new starting/electronics battery

[Pprice01]

1992 Ranger 392v

Was using a group 34 dual purpose Interstate that recently died.

This battery is used for cranking the big motor (200XRi) and driving general electronics and 2 graphs (Lowrance Elite Ti 9 and an older 5” Lowrance GPS/sonar unit).

i understand from research that AGM (my first choice) is not recommended for this vintage motor, so I’m looking for the best battery in Lead Acid chemistry for my needs.

I’ve already decided to move up to a group 31, but which one is the question.

Duracell has a dual purpose with 860 MCA and 100 AmH. Is this sufficient or is there a better option?

Thank you very much for your help.

Paul

[Pprice01]

Some seem to prefer the commercial batteries for cranking, but I’m concerned about the deep draw-down from the electronics. Am I worried for nothing?


https://www.napaonline.com/en/p/NBE7236

[Pprice01]

Or this one, I believe it’s the same battery with different posts:

https://m.samsclub.com/ip/duracell-c...r=Duracell+31c

[CatFan]

My opinion is use the battery you need. The electrical load is the problem, not the type of battery. Keep an eye on your regulators and use OEM parts only.

[184SuperV]

t)

i understand from research that AGM (my first choice) is not recommended for this vintage motor, so I’m looking for the best battery in Lead Acid chemistry for my needs.

Paul

I'm curious - what did you find about AGM's for that vintage motor to indicate AGM's weren't recommended?

I've been using a AGM on my 1989 Yam ProV for a few years.

[DQM]

I'm curious - what did you find about AGM's for that vintage motor to indicate AGM's weren't recommended?

I've been using a AGM on my 1989 Yam ProV for a few years.

The link below is the most common cited source of discouraging using a stator charging system on AGM batteries:

http://www.cdielectronics.com/wp-con...1/194-5279.pdf

Some older Mercury documentation also states that they do not recommend AGM batteries for older stator based charging systems.

I believe the issue is that a AGM battery can discharge quite a bit deeper than a wet cell battery and this can cause the regulators on a stator system to have to regulate a much larger draw, thus causing them to potentially over heat and fail. If you don’t deeply discharge a AGM battery often or at all before it tries to get charged by the stator system you probably will not have any problems.

[184SuperV]

The link below is the most common cited source of discouraging using a stator charging system on AGM batteries:

http://www.cdielectronics.com/wp-con...1/194-5279.pdf

Some older Mercury documentation also states that they do not recommend AGM batteries for older stator based charging systems.

I believe the issue is that a AGM battery can discharge quite a bit deeper than a wet cell battery and this can cause the regulators on a stator system to have to regulate a much larger draw, thus causing them to potentially over heat and fail. If you don’t deeply discharge a AGM battery often or at all before it tries to get charged by the stator system you probably will not have any problems.

Thanks. I did some research after my posting to try and get more info.

One of the major problems I found is it seems some older engines from Merc/OMC and ? did not have voltage regulators in their stator & rectifier charging systems. Not having a voltage regulator could subject an AGM battery to as much as 15-20 volts from the engines charge system which is too high for AGMs.

My old Yamaha 150 Prov does have a voltage regulator to charge my dual-purpose cranking/electronics AGM battery. I use a Dual Pro Sportsman charger to charge boat's batteries when not fishing and Dual-Pro recently told me that the charger was fine for AGMs. So far so good after a few years.