Anybody using AGM battery with Yamaha OB's

H

hardee

New member
We are running twin 2004 Yamaha 40's with 2 Group 24 NAPA automotive weet cell batteries. Here's the situation.

Well, I took the boat into the boat mechanics, They are a Yamaha Warranty Service Center, since I need to replace my 5 year old NAPA auto batteries, (2 group 24's, one in each lazarette) I had found West Marine had AGM Dual purpose batteries on sale. I liked the idea for a couple of reasons. 1. I could maybe avoid putting in a house bat, and put in a pair of group 27's, or 2. IF I add a house battery system it would be AGM (to maintain all batteries of a simular type) and I could put them up under the V-birth and not have to worry about fumes.

So, the mechanic says that Yamaha does not support using AGM or any type of battery other than a flooded wet cell bat. and it is looking like I am stuck with the old flooded type.

Showed it to me from the Yami shop manual. Has to do with, not that it will damage the charging system, but that the charging system will shorten the life of the batteries. Same for Jell or dry bats.

So I am looking for experience with AGM bats and Yamaha charging system. Any Ideas? What are your recommendations? Is there some sort of electrical gadget I can put in line somewhere to make the engines think they are charging the wet cells? I would really prefer the dual purpose AGM due to the way we use power on the boat. Don't really need to go to G-27's if I can put in the AGM dual purpose.

Being seriously mechanic/electrical challenged I am looking forward to the response of experience and knowledge resource here in the pub.

Thanks in advance,

Harvey
SleepyC :moon
 
The Jenny B has two AGM batteries in the starboard lazarette. Yes the long term charge requirements are such that they are easily overcharged with conventional chargers. Never had a problem with the Yamaha 75 charging system and the AGM's, and it's going on 5 years now with the original batteries. Probably because they didn't get many long LONG charges using the engine. I had a battery charger powered by shore power for long term use that was specifically designed for AGM batteries.

If it were a real problem, not a theoretical CYA by Yamaha I think we would all have heard of it long ago. It's definitely not in my F75 manual.

Don
 
The larger Yamaha motors have a different charging system...much more output.... on my 03 Yamaha 40's I think the total output is something like 10 amps....it's really very basic... much more like a lawn mower charging system than a modern alternator system...

I had never thought about the batterys causing my charging problem...but yes... my charging system failed the first time out after I changed the batterys.

Excellent catch... Thanks

Joel
SEA3PO
 
Something doesn't add up. Apparently the AGM battery folks don't feel it's necessary to warn you that your Yamaha will hurt their batteries, but the Yamaha folks do?

I will be following this one closely, as I have twin Yamaha 50's, and three AGM batteries. The engines are rated at 17 amps each. If this is even a theoretical problem, surely it can't be unique to Yamaha. I know some other makes put out more amps for a given hp size.

I have a good on-board charger and most of the time, most of the charging is done by shore power. However, I do run the boat a lot and have taken some very long trips. So far, no problems.

What might Matt Gurnsey or Les Lampman have to say?
 
I have contacted West Marine, and still waiting for a reply from their technical department.

Curious what others are experiencing?

Harvey
SleepyC :moon
 
Many people confuse the charging voltage limits with gel cells with AGM batteries. The AGM will live fine on the charging voltages of the outboards (which are not as well regulated as some smart chargers). But a gel cell will be damaged by voltages over 14.1 volts.

I run an AGM on my 18 foot CC with a Yahama 115 hp, Output voltage of 14.4 volts (same as with my Honda and Suzuki motors)--all of which are charging AGM's --with no problems--and good longivity.
 
All those larger motors have real alternator charging systems.... the 40 and 50hp motors just use a charging loop... much more basic... also low amperage output...

Joel
SEA3PO
 
We are at Steve's house having dinner....we still have not made it home from the Lake Mohave trip... my son in Reno is much better, hopefully we will be heading home next weekend...

Joel
SEA3PO
 
"All those larger motors have real alternator charging systems.... the 40 and 50hp motors just use a charging loop... much more basic... also low amperage output...

Joel
SEA3PO"
Click to expand...

I wondered about the differences there.

From the Yamaha F40C Owners Manuel there are only 3 places that batteries are even mentioned, and there is nothing about what type to not use.

On the page headed "BATTERY REQUIREMENT" (p-1-14) it says
"CAUTION Do not use a battery that does not meet the specified capacity. If a battery which does not meet the specifications is used, the electric system could perform poorly, or be overloaded, causing the electric system damage."

The following specifications are listed:
Maximum cold cranking amps = 380amps at 0.4'F
Minimum marine cranking amps = 502 at 32'F
Minimum reserve capacity = 124 minutes

There is an additional CAUTION: A battery cannot be connected to models that do not have a rectifier or Rectifier Regulator (F40MH). If you wish to use a battery with the above models install an optional Rectifier Regulator.
Click to expand...

The other references are to electrolyte checking and connecting and disconnecting the battery.

This is from my 2004 manual YMMV, but I would sure keep a close eye on the batteries, and keep the warranty papers close in case. I am sure hoping I find that there are no real issues, because I would really like to put in the AGM's with a clear conscience.

Harvey
SleepyC :moon
 
I got up this morning and went to Sears for two AGM's got home installed them and then checked the website Aurgh is Murphy's Law getting ready to strike? Like others have mentioned I think the problem is with gel batterries
 
Marvin, Hope you are OK. Again, I am running twin 40 Yamaha and the issue, according to the boat mechanic is that the Yamaha charging system my shorten the life of the AGM's.

I would sure like to see who has been running AGM batteries with Yamaha OB for the longest time and see how the bats are holding up.

Harvey
SleepyC :moon
 
Thanks Harvey I'm fine on oxygen about 50% of the time and trying to get off it. I have and appointment with Pulmonary Doctor tommorrow to discuss more on a lung transplant. The thing that suffered the most was my boat. While in the hospital my battery switch was left on and boat not plugged into shore power. Something was left on and drained the batteries down to 6 volts hence the replacement. Incidently the factory installed carbon detectors have a low voltage alarm.

I understand your concern about the AGM's especially since it says not to use them in Yamaha literature but everything I've read says the AGM's charging characteristics are very close to lead acid but gel type are different. Sure would be nice to hear of someone using them with a Yamaha 40 or maybe a Honda 40 or 50 they only have a 10 amp charging circuit. I bought mine at Sears and they give a 3 year full replacement warranty rather than the prorated warranties.
 
Marvin,

Thanks for the reply, glad you are doing better. Sorry to hear about the battery drain while you were gone. Good to hear about the Sears battery. I'll have to check with them. I liked the price of the WM for being dual purpose. Best wishes for the Pulmonologist appointment tomorrow. You are living life to it's fullest, enjoy, travel safe and continue to strive.

Harvey
SleepyC :moon
 
It looks like the singles (or big twins) are doing OK with the AGM's. Is there anybody using AGMs for over 2-3 years on a Yamahas system? Specially the little guys 40 or 50's?

Thanks again for timely response. Looks like I have until Tuesday to make up my other mind.

Harvey
SleepyC :moon
 
I just got this back from the Technical Advisor at West Marine:

"Hello Harvey, the Yamaha mechanic is correct in that Yamaha only supports the use of wet cell batteries. I personally checked with Yamaha. This is not because it will hurt the charging/alternator system, but what it does is that some how it shortens the life of the batteries.

There is no way to fool the system that I know about, however from my experience, batteries never last more then 24/36 months anyway. They seem to have a switch that turns them dead.

We do have a 18 month free replacement on the SeaVolt AGM batteries and a five year pro-rated warranty and you are correct West Marine stands behind anything that we sell.

It is really up to you, however if Yamaha states that, I would go with their recommendation.

Thanks,"

Paul Adler
West Marine, Direct Sales
800 262 8464
Click to expand...

If those AGM's are going to last only 2 years, I'm not much interested. Too expensive for only 2 years service. NAPA or Interstate will get my business.

Think I wnat to hear from the battery manufacture, but I guess it might nopt make any difference. The Query continues.......

Harvey
SleepyC :moon
 
It looks like the AGM's are out of the running. Too bad that the Yamaha does not charge the AGM's with the finesse available with today's technologies. Seems like there must be a way, but I am running out of time so........

Next question. Has anybody tried getting a group 29 into the lazerette (starbd, and port) on a 22 Cruiser? My boat is in the shop in Port Townsend and I am trying to do this via remote control. Interstate makes a wet cell, Marine/RV "Deep Cycle Cranking" battery (#SRM-29) with the power requirements I am looking for, but I don't know if it will fit into the hole. The size is 13" x 6 3/4" x 10"high.

Thanks again,

Harvey
SleepyC :moon
 
Somehow over the weekend I missed all this discussion, but Harvey and I have been going back and forth on the side.

I know that Gel cel and AGM like a different charge curve than the wet cels.

Looks like the AGM needs 14.7 volts to get the charge going, only .1 volts higher than wet cel. In fact, the recommendation is to use a wet cel setting if a specific AGM setting is not available on the charger.

In the West Marine advisor on Smart Battery Charging, it says that a 200 amp hour battery would be charged at 40-80 amps during the Bulk Charge Phase.

This may be the problem with the Yamaha 40's and the AGM battery, as the motors can't produce enough amperage . My concern would be that the AGM batteries may never get a full charge from the small outboards, drastically shortening their life.

If the bulk of use of the boat is dock to dock, then using the 110V system charger would probably keep the batteries in good condition.

But-

I think many C-Dory owners enjoy being on the hook and without 110V hookups, and I know that Sleepy-C has two C-PAP machines going overnight, which will put a drain on the battery running the engines for a few hours will not produce enough amps to restore the charge.

With AGM batteries at twice the cost of a dual purpose wet cel, it would be an expensive lesson to learn if the AGM's fail after two years (especially when Harvey is getting longer life out of his wet cels).

Even adding extra batteries for extra capacity is problematic with the twin 40's, as the alternator output can't produce enough amperage to fully recharge the batteries.

Now, if we all wanted to chip into Harvey's battery purchase to support an experiment in AGM battery use with small outboards, I'm sure he would be happy to provide progress reports. :lol:
 
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