Regulating voltage output for AGM batteries?

[Peter_C]

I have a 1993 Evinrude 40hp (40RETB) motor that I added a starter and starter solenoid to (It was rope start originally, so now I have the best of both worlds). Right now at the end of a long weekend, my battery which is a Hawker Odyssey is pretty much dead from starting the boat and running a Garmin GPS/Fishfinder. So it is time to start charging the boat while the engine is running. I just bought from Ebay a rectifier that I will mount to the engine. Kinda funny because the one that "bolts in" is actually for a 9-15hp, but the one it calls for, which I bought, I have to modify the ends of the harness. Anyhow all over the manufacturers say "DO NOT USE A MAINTAINENCE FREE OR AGM BATTERY WITH THIS RECTIFIER AS DAMAGE TO ELECTRICAL PARTS MAY OCCUR!!!" Well guess what kind of battery I have? Yup an AGM. Has anyone added in a regulator to keep the battery voltage steady at under 15 volts? I am sure there is something available that just goes inline. Of course building one from scratch is an option (The internet knows all), but it sounds much easier to install some type of premade regulator inline, and let me get back to welding up my boats custom Wheeleez mounts so I can beach launch with ease, then comes sewing up the slings for launching off of piers. I spent enough time trying to figure out which rectifier I needed and where to get it from, so I am reaching out for some advice, and no I am not going to put a flooded cell battery in.

Any help would be appreciated.

 

[lmuss53]

Re: Regulating voltage output for AGM batteries?

I have read a post here at iboats about using the rectifier/regulator off of a newer 70 hp to regulate the power off of these smaller outboards, but can't say exactly where the post is. I am interested in the same solution for my 55.

 

[Peter_C]

Re: Regulating voltage output for AGM batteries?

Wound up doing a little research, but have only made it thru about 200 threads so far. There are plenty of threads but nothing with a definitive part number. Someone did recommend a regulator inline, like the one in the link below.

http://www.fullthrottletahoe.com/fu...ages/catalog-specs/09SnowPages/09Snow 243.pdf

A little more info on my motor. The stator is a three wire unit, that was already in place, the wires are just capped. I can now add a regulator, or rectifier/regulator unit. I do not have water cooling capability, at least not without major modifications. At this point I know where to get an ultra cheap rectifier and would prefer to have a stand alone voltage regulator installed inline. My motor does not have a 12 volt power supply that is switched on when starting, just a push button starter and the kill switch, so no 12 volt switched power source available. No tach either.

Edit: http://www.drolsum.net/johnson/regulator.html

Anyone ever tried a self exciting Delco regulator? They are cheap at around $11.00, small, and would be easy to retrofit. I think I have one on an old alternator, but need to tear it down to find out.

 

[Peter_C]

Re: Regulating voltage output for AGM batteries?

My Fleabay rectifier came in the mail today. No one has any thoughts on adding some other type of regulator between the rectifier and the battery?

 

[Haffiman]

Re: Regulating voltage output for AGM batteries?

This one should work out for you:
http://www.boyerbransden.com/pdf/PBOX109.pdf

 

[Peter_C]

Re: Regulating voltage output for AGM batteries?

An update since my charging system has been working for a while now. I wound up using a motorcycle rectifier/regulator and it has been working great. Charges my AGM battery without over charging. There are a ton of them available on Ebay both new and used. I only used one bolt to hold it down to the outboard, and it doesn't seem to get that hot. Although I also have pretty lite electrical demands with only a starter motor and a depth sounder. Plus I have a Ctek battery charger that is used at home to keep the battery fully charged. Cutting the ends of the wiring off and adding new connectors was easy with a total install time of less than 15 minutes.