Changing pull start to electric start question about charging battery

rkf_bomb

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  • / Changing pull start to electric start question about charging battery
Hey all,

I acquired a Briggs model 287707-0227-01 engine(14hp, I/C). I put it in my 36" commercial walk behind mower as the original Kawasaki engine decided to throw both valve seats. The kawasaki was pull start and the briggs is electric. I start it with a starter/charger I have that can roll out 200 amps for starting. I'm going to add a cheap lawn and garden battery but not sure how the charging system will affect the battery. The Briggs uses a single diode coming off the stator to charge the battery, not your typical voltage regulator. The battery will only be used to start the motor as there is nothing else electrical on the mower. I guess I'm wondering if the battery is charging while I'm using the mower if it can mess the battery up since the battery will probably not even really need to be charged. Hope this all makes sense. I know how to wire everything up. I'm just concerned about 'overcharging' I guess. I thought about just using a charging tender on the battery between cuts.

I should also mention this is for my own yard, not commercial. The mower is used once a week for 20-30 minutes. I thought about just using my charger/starter to keep starting it but if/when I have to cut the mower off while cutting lawn, or if it dies for some reason, I either have to push it back to garage or drag out the 100' extension cord to hook up the starter/charger.

For those wondering why not just fix the Kawasaki it's because there are very few parts available. I actually did fix the exhaust side at one point. Ran great for a minute then threw the intake seat. Thats when I found out there are very few parts available for the engine. The mower is 20+ years old. And I got the Briggs for free from my brother!

Thanks for any advice,
Ron
 

ILENGINE

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  • / Changing pull start to electric start question about charging battery
the single diode charging system is only putting out about the same amount as a float charger. 3 amp max. Since the engine is set up for it might as well connect it to the battery and let it recharge the battery while running to slightly replenish what was consumed with the electric start.
 

rkf_bomb

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  • / Changing pull start to electric start question about charging battery
Copy that. Thanks!
 

mitchstein443

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  • / Changing pull start to electric start question about charging battery
wait..
first thing to do is check the voltage it is putting out.. to charge a 12v garden battery the voltage must be between 12.2 and 14.5 volts with 13.8 being perfect.. check it at highest and lowest rpms.. of course going too low at low rpm is fine as long as your running the mower not at the lowest rpm.. just mke sure it puts out at least 12.2 volts and no more then 14.5.. if it does the battery will be fine and dandy..

If you go over the 14.5 limit the worst thing that will happen is the battery will burn out after a few runns, if it sits consistantl below 12.2v the battery will never fully charge back up and would need a booster charge after 8 or 9 starts...
 

ILENGINE

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  • / Changing pull start to electric start question about charging battery
@mitchstein443 This is a non regulated 3 amp charging system mower. Not enough amps output to damage the battery. Actually there isn't enough output to recharge the battery after a start unless run like 5 hours. This type of system runs at a deficit for recharging the battery. Eventually it will run the battery down even with the charging system working properly.
 

Born2Mow

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  • / Changing pull start to electric start question about charging battery
IMHO, 3A should be fine if you run your mower for the usual 1+ hour of mowing per week.

The weakness in these low rate, unregulated systems is that there's no way to raise the charge rate when the battery gets in a low state. But there are things you can do that will insure a much higher success rate...
  • Once you crank the mower, leave it running. DO NOT start and stop several times. Check the oil and air in the tires before cranking. When you finally crank the engine, be ready to run it for the duration. Leave it running while getting rocks and other obstacles out of the way. Simply maximize the charge time, while minimizing the drain (the number of starts).
  • Keep your all battery cable terminals (both ends of BOTH cables) corrosion-free. Have the best electrical connections possible. This might call for treating the connections with electrician's anti-oxidation compound.
  • Fit a battery switch so that the battery doesn't dis-charge while it's sitting. The one I use cost about $9 and does a beautiful job. CLICK HERE. There are 3 types of these for different battery post types: round post, side posts, and motorcycle.
Hope this helps.
 

mitchstein443

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  • / Changing pull start to electric start question about charging battery
@mitchstein443 This is a non regulated 3 amp charging system mower. Not enough amps output to damage the battery. Actually there isn't enough output to recharge the battery after a start unless run like 5 hours. This type of system runs at a deficit for recharging the battery. Eventually it will run the battery down even with the charging system working properly.
atually, 3amps is more then enough to charge the battery.. unless the battery is totally drained. for a siply turnkey start the battery will be fully recharged in under 10 minutes at 3 amps.. 30 minutes at 1 amp..
The battery will only absorb what amperage it needs to charge fully provided, the voltage does not exceed 14.5 volt.. If you put 20 volts into any 12 volt battery at just about any amperage you will shorten the life of the battery to next to nothing.. Trust me, I have done enough solar setups to know exactly hat goes on inside a lead acid battery and all thier tolerances.. best thing for a lead acid battery is a trickle charge at .25 amps over night.

A good example is a 50% discharged standard battery from a riding mower attached to a 10 amp regulated charger at 13.8 volts will only accept 2.5 amps to recharge.. so 3 is more then it needs...
 

ILENGINE

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  • / Changing pull start to electric start question about charging battery
atually, 3amps is more then enough to charge the battery.. unless the battery is totally drained. for a siply turnkey start the battery will be fully recharged in under 10 minutes at 3 amps.. 30 minutes at 1 amp..
The battery will only absorb what amperage it needs to charge fully provided, the voltage does not exceed 14.5 volt.. If you put 20 volts into any 12 volt battery at just about any amperage you will shorten the life of the battery to next to nothing.. Trust me, I have done enough solar setups to know exactly hat goes on inside a lead acid battery and all thier tolerances.. best thing for a lead acid battery is a trickle charge at .25 amps over night.

A good example is a 50% discharged standard battery from a riding mower attached to a 10 amp regulated charger at 13.8 volts will only accept 2.5 amps to recharge.. so 3 is more then it needs...
You guys can argue your point with the Briggs factory service techs which is were I got the 5 hour recharge time for the single wire half wave rectifier non regulated charging system. This charging system and how it is not adequate for most homeowner operating periods has been discussed in more than one of my annual service update schools over the past 23 years.
 

rkf_bomb

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  • / Changing pull start to electric start question about charging battery
Thanks y'all. Could I get a regular voltage regulator instead of the single diode?
 

ILENGINE

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  • / Changing pull start to electric start question about charging battery
@rkf_bomb You are trying to take a simple charging system that has been in use over 60+ years and make it complicated. Connect the wire with the diode directly to the + side of the battery and stop worrying about it.
 
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