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Discussion Starter · #1 · (Edited)
Okay. Lawn tractor battery. 2 seasons old. I think its already bad, but not sure.
Tractor would not start. So, I jumped it off to cut grass.

Later I found the battery a bit low on water, so I added water to the correct level.
Put on slow charge. 2 amp. About 3 hours.
Checked battery voltage and found it at 6 or so volts.
I now have it on charge again. Automatic charger. 2/10 amp. I am pretty sure its toast and do not want to go through this again. This is a special motorcycle (sport type machine) batteries and cost close to $100. Compact, but serviceable.
No room for a regular tractor style battery unfortunately.

I am going to check the charging circuit next. I think its okay. Magneto ac voltage to regulator/rectifier then dc volts around 14 vdc? Is this correct.

The tractor manufacturer told me it might need the valves adjusted?
I did not get his point, but after turning the flywheel with my hand I do now. Its 14 HP, but its very hard to turn in spots.
He said this may be causing the battery to work to hard and cause premature failure? Never heard of it.

Any ideas? The original battery lasted for almost 10 years.
I have now bought 3 batteries in 5 years.
I take it out every fall and clean it, add water if needed and apply slow charge occasionally or as needed. Its sits on the bench all winter long.
 

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Wish I had something more intelligent to add but for what its worth I keep my motorcycle battery on a trickle charger during the non-riding season (sometimes up to 4 or 5 months). I've never had an issue.

Pete
 

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14 volts is a little high for a car battery, I think 13.6 is tops. I charge my deep cycles at 28.7(24 volt battery) but the plates are thicker on a deep cycle. Maybe the low water is from overcharging. Heat kills batteries, so does prolonged low voltage. They get a sulfide coating(rust) and can't transfer energy. As far as too much load, that sounds like a stretch. It's not like you crank on this constantly.

Ok, I'm wrong. I looked it up.

TESTING the ALTERNATOR, is it good or bad?

To charge the battery, the alternator voltage output has to exceed a minimum charging voltage. This minimum charging voltage is 13.8 volts dc across the battery terminals, or at the output of the alternator. A single lead-acid cell starts to charge at anything over 2.25 volts. Since a 12 volt battery has six cells, any 12 volt lead-acid battery needs at least 13.8 volts to start to charge. This voltage will be enough to fully charge or maintain the battery on a trickle charge, but charging time will be very long at 13.8 volts.

To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts. Above 14.5 volts charging voltage, batteries have a greatly increased tendency to release excessive acidic vapors, hydrogen gas, and to corrode things around the battery. The battery terminal charging voltage must be less than 14.7 volts to prevent excessive gassing. Charging voltages over 14.7 volts can prematurely dry the battery by boiling out electrolyte, and increase risk of a battery hydrogen gas explosion.
 

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Valve adjustment is never a bad thing if you have the specs and its been a while. Seen where the exhaust adjustment was so loose that it was almost impossible to pull start, in other words you couldn't relieve any compression.
 

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Discussion Starter · #5 · (Edited)
14 volts is a little high for a car battery, I think 13.6 is tops. I charge my deep cycles at 28.7(24 volt battery) but the plates are thicker on a deep cycle. Maybe the low water is from overcharging. Heat kills batteries, so does prolonged low voltage. They get a sulfide coating(rust) and can't transfer energy. As far as too much load, that sounds like a stretch. It's not like you crank on this constantly.

Ok, I'm wrong. I looked it up.

TESTING the ALTERNATOR, is it good or bad?

To charge the battery, the alternator voltage output has to exceed a minimum charging voltage. This minimum charging voltage is 13.8 volts dc across the battery terminals, or at the output of the alternator. A single lead-acid cell starts to charge at anything over 2.25 volts. Since a 12 volt battery has six cells, any 12 volt lead-acid battery needs at least 13.8 volts to start to charge. This voltage will be enough to fully charge or maintain the battery on a trickle charge, but charging time will be very long at 13.8 volts.

To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts. Above 14.5 volts charging voltage, batteries have a greatly increased tendency to release excessive acidic vapors, hydrogen gas, and to corrode things around the battery. The battery terminal charging voltage must be less than 14.7 volts to prevent excessive gassing. Charging voltages over 14.7 volts can prematurely dry the battery by boiling out electrolyte, and increase risk of a battery hydrogen gas explosion.
Good read. Thanks.
Thinking back when I installed this battery, I did not have 14.5 volts at the terminals when it was running.
But since it was a brand new battery, I assumed that was why the reading stayed almost the same. Running or not running.
Could be the charging circuit all along.
BTW. I do have 11.5 volts right now. Its been on charge (5 hours) at 2 amps setting.
So maybe, just maybe I can save this.

Edit. I assumed the charging circuit used a magneto. But my parts list shows it as a alternator and i cannot find a regulator or rectifier yet.
Looks like the wires go straight to the battery from the engine via the solenoid?
I will need to pull the sides off to really see in there.
Tomorrow. Beer time.

Valve adjustment is never a bad thing if you have the specs and its been a while. Seen where the exhaust adjustment was so loose that it was almost impossible to pull start, in other words you couldn't relieve any compression.
Yes, when I tried to help the battery turn over the engine, I tried to help it by turning the flywheel. I could barely turn it at one position.
And I did hear the "hiss sound when it (valve opened)?
So, that either reinforces the valve needing adjustment or its normal and i don't know what the **** I am doing.
Thanks.
 

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At top dead center with the piston coming up is when its toughest to turn because both valves are closed, however if the exhaust doesn't open the pressure is never released. The mechanical and gas portion of the generators has been the biggest learning curve for me, though while reasonably mechanically inclined, I don't do it everyday and gas piping is whole different trade (which I don't do, but need to know enough to know whether they did their job correctly or not).
 

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14 volts is a little high for a car battery, I think 13.6 is tops
NO not really !
Most battery manufacturers recommend charging voltages of 13.6 to 14.4 max.

So 14v is ideal charging voltage for a battery charger.

Short charge cycles will go as high as 14.4.

But it causes more gassing.


The thing is that modern batteries are not as well manufactured as old batteries, at least not in the long life area.
So batteries don't like sitting around doing nothing,
A trickle charge will help, but constant or regular use
is the best way to get maximum life from a battery.

Why don't you take it for a short drive once a month.
Will help enormiously !
 

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dmxtothemax said:
NO not really ! Most battery manufacturers recommend charging voltages of 13.6 to 14.4 max. So 14v is ideal charging voltage for a battery charger. Short charge cycles will go as high as 14.4. But it causes more gassing. The thing is that modern batteries are not as well manufactured as old batteries, at least not in the long life area. So batteries don't like sitting around doing nothing, A trickle charge will help, but constant or regular use is the best way to get maximum life from a battery. Why don't you take it for a short drive once a month. Will help enormiously !
You should have read the rest of my post.
 

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NO not really !
Most battery manufacturers recommend charging voltages of 13.6 to 14.4 max.

So 14v is ideal charging voltage for a battery charger.

Short charge cycles will go as high as 14.4.

But it causes more gassing.


The thing is that modern batteries are not as well manufactured as old batteries, at least not in the long life area.
So batteries don't like sitting around doing nothing,
A trickle charge will help, but constant or regular use
is the best way to get maximum life from a battery.

Why don't you take it for a short drive once a month.
Will help enormiously !
I can see it now, a ride to the convenience store on a ride on mower.
 

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Discussion Starter · #12 ·
I think the battery is going to be okay after all?
Yesterday when charging at the 2 amp setting the meter on the charger showed little if any charging occurring. So I moved the switch to 10 amp. I had nothing to lose. I removed all the cell caps and left it for 4 hours.
When I went to check it, the meter showed the needle at half scale and the battery disconnected reading 12.5 volts.

So, I looked for the manual on the charger and could not find it. Today they sent me the manual via email.
This charger is supposed to shut off by itself! I had no idea it was supposed to charge until the "electronic" charger got a reading of 14.5 volts and shut itself off.

So back on charge again this am and waiting for the charger to turn off.

Next is the charging circuit. I am now thinking the charging circuit has been my issue all along.
The battery is only needed to start it and thats all it has done is start, it may have never received a charge from the tractor.

So I will follow wires and take measurements until I resolve this issue.

Thanks guys!
 

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Discussion Starter · #14 ·
Interesting John
especially since i'm having similar problems with my lawn tractor today~CS~
Update: Battery okay. Battery has run for two seasons with not one charge from the machine. Only the half ass charge I have put on it.

I scoured the internet for answers and now have the alternator from under the flywheel removed.
I cleaned it, cleaned the magnets under the flywheel and checked for continuity. The alternator read 1.6 ohms (with the diode out of the circuit) and according to what I read this is correct. All magnets are strong.

My machine has a dual output alternator. One wire (white) is just for headlights and the other (red) is for charging.
The alternator also has a diode connected in series to the charging wire. This wire travels to the ignition switch and i think finally to the battery. There is no regulator.
The diode is located directly as the lead leaves the alternator.

I took an ac voltage reading at the alternator leads (direct output) without the diode in the circuit and got 37 ac volts. This is supposed to be good.
Reading with diode, output is 12.7 dc volts (Red) wire to ground Not enough to charge the battery.
But diode checks good. 0 volts in one direction and .500 volts the other way.

So, I am not sure what to think. My neighbor had two alternators just like mine that he thought were good. None of his worked either. Same output too.
But I cannot be certain his were good either.

I could not get any parts over the weekend, so tomorrow morning I am getting a new alternator. It comes with the diode already connected.

Any other ideas? The charging wire goes to the key switch. Is it possible there is anything special inside this switch? It has 6 pins.
I did notice the pin my wire is on is grounded. That has me puzzled.
So, I am thinking the key switch could be the problem?

If this had been a paying job, I would have lost my ass unless I was getting paid by the hour.
 

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John;

What are you using for fuel in your machine?

I use 89 octane in all my toys and they run well.

Also some manufactures recommend 89 or better...




http://www.echo-usa.com/getattachment/7011c2f4-035a-47cb-82e5-cf7038faee8e/SRM225es1112_022014_2.pdf

Fuel Requirements

Gasoline
- Use 89 Octane [R+M/2] (mid grade or higher) gasoline known to be good quality. Gasoline may
contain up to 10% Ethanol (grain alcohol) or 15% MTBE
(methyl tertiary-butyl ether). Gasoline containing
methanol (wood alcohol) is
NOT
approved. ECHO brand Power Fuel

is 93 octane, ethanol-free fuel
premixed with ECHO Red Armor
®
engine oil at 50:1 ratio. Use of ECHO Power Fuel

is recommended to
extend engine life in all air-cooled 2-stroke and 2/4-stroke hybrid engines.
 

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Black Dog said:
John; What are you using for fuel in your machine? I use 89 octane in all my toys and they run well. Also some manufactures recommend 89 or better...
Same here, except I add Sea Foam.
I noticed that Stable now comes in different types, including one for 10% ethanol.
 

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Discussion Starter · #17 ·
John;

What are you using for fuel in your machine?

I use 89 octane in all my toys and they run well.

Also some manufactures recommend 89 or better...
Same here, except I add Sea Foam.
I noticed that Stable now comes in different types, including one for 10% ethanol.
Why would gas have anything to do with the battery charging system?
It runs just fine.
It will not charge the battery. That is what this thread is about.
 

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John, I think you had this deal figured out when you could not turn over the engine by hand, when you have that kind of a bind the motor is going to work extra hard and drain the battery in no time. This spring I went to fire up my 12 yr old single cyl Craftsman, after charging up my battery with trickle charger, it would just barely turn over and eventually battery would die. I got a new battery, charge it, same thing. Take battery to work where we have a real tester, element puts like a 100 amp load on battery. Good. Check solenoid, cables etc, good. Buy new starter motor online for $50, install, no go. Damn grass is getting taller and laughing at me now. Jump to my car with engine running so I can crank away without draining battery and starter motor gets smoking hot. At this point I am sure I have a mechanical bind, maybe something broke in the engine. Buy new rider from Lowes so I can mow. Than I read the good gentleman's post about valve timing and I am sure thats my issue as well, just the way it turns, like there is one tight spot. You will drain a good battery in no time trying to start a bad engine, probably nothing wrong with your electrical system.
 

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John, I am willing to bet that you need to adjust the valves. If it is turning over hard, more then likely that's the problem. It's an easy fix. Just need se feeler gauges. Did the mower backfire when you would shut it down?
 
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