In reference to my original post on 06/02/07, I did make a couple of errors in my report. As was pointed out, the battery I was referring to was an AGM, not a gel cell.

Second, the dollar amount for the repair was reported incorrectly as $1,300. The actual amount was approximately $1,000. I had forgotten that the water pump and spark plugs were replaced on the same work order because of the long period of non-use. Those two items, plus tax, amounted to about $300 of the actual cost of $1,293.

The electronics repair included the following parts: Stator; trigger (timer base & sensor assembly); and power pack.

I contacted the mechanic today and he told me that he was never fully satisfied that all of the above components went bad at the same time. This was very unusual for him. So; he told me today that he retained my old parts and even used some/all(?) of them as replacements on another motor repair; and, that they were definitely bad as his diagnostics had indicated. So; he felt more comfortable with his original repair and costs for my motor. As I mentioned before, his service is of the highest integrity.

He was busy and I forgot to ask about the mechanics concerning the compatability of the AGM or gel battery with a stator. He had left the shop to run an errand, and his co-worker answered my second call. His answers to my questions offered his opinion, and he stressed that the following was only his opinion:

Older batteries can sometimes show up to 16 volts on the charger that could possibly cause a spike to the stator.

Gel cell and AGM batteries can produce higher than normal voltage and send too much voltage to the stator.

The regulator controlls the amount of voltage to the battery.

He was also busy, and we didn't get into the subject of internal fuse protection for the electronics.

That information cleared up some of the questions I had and gave me a little more understanding of why both Bombardier and Mercury only recommend lead, acid battery for starting.

For an expensive piece of equipment used in my sport of choice, I will always err on the side of caution when I have enough information to make a decision.

I hope the good information submitted by all in these two posts will be of some benefit. I also believe that this subject is not common knowledge because of qualified mechanics not having definitive information and because of anglers with a lot of experience not having the same opinions. Again, I apologise for my errors in my reporting.

no prob...thanks for coming back with the answer...I never knew that the battery could affect all those components - electricity is a strange thing.........

as to the fuse question, when you mentioned "electronics" I was thinking boat accessories (fishfinder, etc) vs. actual engine parts - my bad.

Cajun, education is expensive, ain't it? As far as stators, they're just weird, especially Merc stators.

One thing I know: nothing will take your mind off of it like fishing!

Artie

How right you are, Artie!!

So; I think I will just go in the morning.

Ken

Cajun Ride

I'm not disputing a Certified O/B engine Tech's word but it's strange to me that an AGM Battery can cause a 16vt voltage spike while a conventional lead acid wont??

Besides AGM's being Sealed and Maintenance Free..

The basic difference between AGM and Lead Acid Batteries is a Fiberglass envelope surrounding each plate on the AGM Battery. Other than that as I understand it they are identical??

The reason AGM batteries last longer is the Glass Mat envelope keeps the charging plates from being coated with sulphur and Lead Oxide deposits like standard Lead Acid Batteries can get.

Over voltage because of AGM just seems like Bad Information to me??

Bazz

I've never heard of such a thing as overvoltage in an AGM battery or can figure how any battery can contribute to a spiked voltage from a charger or motor charging system. Both wet cell and AGM batteries are similar in charging voltages that they can accept.
Since most AGM battery lines make starting batteries for outboards as well as cars/trucks I think that the information may be bad.

Bazzetx and Allison,

Thanks for the further input. I am certainly not a mechanic. When the age of points, plugs, condensers and rotor caps was over, I was too!

First, let me re-qualify my less than sufficient prior statements. I do not know whether the second local mechanic I talked to is certified, or not. He gave me an opinion, and stressed that it was his opinion only. My regular mechanic, who suspected that my motor electronics problems could have been caused by the AGM Optima, automotive-type starting battery, was demonstrated to be correct in his opinion by the official Bombardier tech. advise to not use this type of starting battery with a stator. My mechanic is certified and receives ongoing training and education in this field.

I have not had any in-depth discussions with knowledgeable sources about the differences in performance as relates to AGM, gel cell and marine AGM batteries in conjunction with a stator.

Again, there are several things which lead me to believe that there is not yet enough wide-spread knowledge about this subject
for the average boat owner:

One - A certified mechanic only had a suspicion about my malfunction based on his prior expeiences with what we thought, or what I understood he thought, gel cell starting batteries.

Two - Differences of opinions among persons with long time experiences in boating, the mechanics involved and an extensive knowlege about the outboard electronics and batteries as reported in these discussions.

Three - The official positions of both Bombardier and Mercury to use lead, acid batteries only with at least some of their products as has been reported in previous posts on this subject.

Four - Not knowing whether you, or any of the posters on this subject are certified mechanics, or are persons with long time experiences and extensive knowledge, (And; this lack of information about the posters makes absolutely no difference in my mind. Your responses are appreciated by me. I do want to make absolutely clear that this statement is not any type of negative reflection on your statements nor opinions, and is definitely not any sort of play on words.)

Based on the premise in the long, drawn out paragraph above, and my being used to professional mechanics adding to many of the discussions in this excellent forum, I am somewhat surprised that no professional, certified mechanics have identified themselves as such, and offered an explaination in this rather long series of postings on this subject. Again, I do not believe that the exact performance differences between the various batteries are well known, even by the professionals.

I will again state that even though my understanding about this subject is imperfect, the information available to me strongly indicates my use of a lead, acid battery only for starting my old, cantanerous, Johnson 200; and, that my posts were submitted only to increase awareness of a perceived conflict with some equipment.

I do not have any further need to confirm my decision; but, I would be interested in a definitive explaination of what could cause a conflict between a AGM, gel cell or marine AGM battery and a stator system.

If anyone has any further interest in this subject I would suggest contacting your motor mfg. for a recommendation and also for a detailed explaination of the reasons for the recommendation. If anyone does this, please make the explaination known on this forum.

Thanks again to all of the posters who are trying the clear up my fuzzy mind. It's not your fault that I remain confused, but I am comfortable with my decision to stay with lead, acid batteries for now.

Cajun Ride

I'm a Certified Aircraft Mech myself.. 10/4 on the electronic ignition.. it's all Voodoo Magic in a $$$$ box!