smoke your batteries

[John Baumgartner]

FYI, I just found out that your outboard could be frying your batteries. I have a Tohatsu 9.8 HP on my boat. I found out the electrical output of this engine is a rectified magneto output that can range from 12 volts up to 17 volts / 1.5 amps (idle) to 6 amps (wide open). I use expensive SeaGels for my house and starting batteries and expected my outboard to charge them, after putting an o'scope the the electrical output of the engine, I was amazed at what I found. East Penn Manufacturing, the makers of the batteries state that to apply more than 14.2 volts could seriously decrease the life of the batteries, during the bulk stage of charging the voltage should be 14.1 volts, Acceptance phase 14.1, and during the float phase 13.7 volts. I'm in the works of figuring out how to regulate the outboard voltage to a happy 14.1 volts.Since a migneto is used you don't have a field voltage to work with as with using an alternator. Any help would be great.

 

[Doug Cross]

OVERCHARGE

YOU MIGHT CHECK WITH A RADIO SHACK TO SEE IF THEY HAVE A VOLTAGE LIMITER.YOU MIGHT INSTALL A SHUT OFF SWITCH

 

[Crazy Dave Condon]

never a problem

As a dealer who has used Tohatsu which also makes the Nissan along with alot of manufacturers motors, I have never experienced this problem with either a single or dual battery system when using the 9.8 with electric start. I was using normal marine batteries. The 9.8 is the same block as the 8 hp. I would suggest that you look at your wiring. I have two gel cells on a 260 being charged by a Honda 9.9 and that is not happenning either.

 

[Bob Johnstone]

Regulators

I also had a problem with the jel batteries and contacted Solar Electric www.solarelectricinc.com ph 858-581-0051 fx 858-581-6440. West Marine did replace my first and second battery plus a final exchange back to a regular marine wet cell battery.

 

[Steve Dion]

never a problem either.

We have a 15hp Tohatsu on our RIB. It is also charges our small gel cell and has not had any problems with cooking it.

 

[John Baumgartner]

Crazy Dave

I haven't had a problem yet, but I haven't had the boat in the water. I just installed my second gel battery in the port head "wet Locker" using #6 gauge wire. I have a lot of money in batteries ($400 ), so I looked into the charging source and called up the Tohatsu motor people and they gave me most of the information about the motor charging system voltage and current outputs.My concern was not with short term charging with the outboard but long term. I go to the ICW and might travel days running the outboard so than the accumelitive effects would shorten the life of the batteries, I'm looking into designing a voltage controller with a consent output of 14.1 volts and varying the current with engine RPMs. OH ya did you get the aluminum suppor that I sent you, Love my Hunter, now the weather needs to clean up to go out, still haven't sold my San Juan yet hope you had better luck with the one your are selling