Battery Recharging Question

I searched the forum and learned that an electric start PW, which I have, recharges the battery. How does this work? I’ve gone through two batteries in seven months. I use a regular Advance Auto battery.

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Most motors use a rectifier. I’m happy if a battery last 6 months.

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So is the rectifier supposed to work like a vehicle alternator?

I’m not happy unless a battery lasts for 3-5 years but I spent 15 years developing and teaching battery maintenance training programs for the military so i’m probably have higher expectations than most for battery life. So what’s generally the problem?; not enough voltage from the charger to completely top off the battery. Might sound crazy but a flooded cell 12 v battery at 12 volts is about 50% discharged. A fully charged and rested flooded cell 12v is 12.6-12.8 volts. An AGM will be at 12.9-13 v. AGM’s use hotter acid than flooded cells hence higher resting voltage. If you are charging a flooded cell and the charger doesn’t get to 13.5 or higher the battery will be under charged, for an AGM it needs to be t 14.2 V. Very few chargers or alternators on the market today get to those voltages. WHY? they don’t gas at lower voltages. You never want an AGM to gas but it’s not a big deal on a flooded cell as long as you monitor the fluid level and only replenish it with distilled water. OK, nuff’ said. That’s the Reader’s Digest Version


All a rectifier does is convert AC current to DC.


Bought a battery tender to see how that goes. Thanks!

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I’ve been running into a similar , though much more pronounced, problem lately. Every few days i’m having to recharge the battery on one of my older units. Was researching the problem when this thread caught my eye.

Do any of you mechanics have a suggestion? (yes, the battery has been tested and even swapped out with a battery from another unit. Both batteries performed fine on one unit and both died on the other unit.)

Nothing will charge like an alternator or trickle charger. Figure 15 starts a day, 75 starts a week, 300 a month, that’s 1800 starts before replacing it for $50. Just a business expense.


Good point.

1800×average job price=enough money for a new battery and then some

Many electric start engines have a charging system on them to maintain the battery. Some have fuses. Have you checked to make sure the charging system is working? Also, the charging system only puts out enough amps to maintain the battery. It will not recharge a discharged battery or bring a dead battery back to life. Your battery should last several years.

Checked all of that, swapped batteries between 2 of my units and still end up with one unit’s battery losing charge over a few uses. To me it seems obvious that the recharge system isn’t working but I’m having trouble trying to find a replacement generator to go on the Honda GX690.


Search online for charging coil, about $75. Or, rectifier, about $200. It can only be one of those 2 of your wiring is good and no blown fuses.


Thanks a lot. I do appreciate it.

Rectifier is easiest fix. Check and see what the system is charging at.

Hey @Innocentbystander quick question. Currently out working and having some issues and this thread was closer thing I could find. My battery on my gx630 is a year old. Washer didn’t start this morning so I had to jump it on first job. It was running fine until the trigger was let go and it had to bypass. Right as the k7 went into bypass mode the washer turned off. Does this sound like something an old dead battery can cause or something else? Thanks in advance!

Sometimes my washer will stall if I let off the trigger before the engine warms up a bit.

But a dead battery means you need to put a tender on it, or replace.

The battery only role in the gx690 is in the starting feature, and fuel cut solenoid. So, if its going dead and electrical current has gaps, the fuel cut could be activated. I’m not sure how thats related to trigger pull tho.

If it starts, it’s not the battery

Didn’t start unless I jumped it