Post the model number of your ENGINE.

Walt Conner

TRACTOR - - MODEL NUMBER 917.275400
BRIGGS & STRATTON ENGINE-MODEL NUMBER 31H777, TYPE NUMBER 0297-E1

You only have a 3 amp charging system.
It'd take 10-12 hours running (at high engine speed) to fully charge a totally discharged battery.
Suggest you get the battery fully charged elsewhere to give it a chance.

The battery was brand new a week ago, what would cause it to lose it's charge ?

This is probably due to a failed rectifier diode, which is preventing the battery from recharging during use.
The diode looks like a "lump" in the charging wire coming from the alternator. Briggs part # for the diode is 391507.
It would be wise to test the diode before just arbitrarily replacing it.
There is a possibility that the alternator stator could be defective, but that too can be tested.
If you have a VOM (multi-meter) and can use it (or follow some instructions) we can help you through the tests. But if you are not equipped, best you let a pro shop determine the cause.
Cases like this can often occur when when a battery is connected "backward" (reversed polarity) or if jumper cables (hot shot?) are connected in reversed polarity.
So, think back.............if you can remember possibly connecting the new battery backward (even momentarily) or maybe connecting for your hot shot with the cables reversed..........that may have blown the diode.
It is also possible that the connector that joins the engine harness to the chassis harness has become damaged or corroded, or even.....disconnected.

On many occasions I've seen the connection between the wiring and the rigid lead on the diodes done very poorly and providing no protection against vibration causing the rigid diode lead to break.

I always add a piece of cable tie or popsicle stick to support the diode connections when I tape it back up.

Radio Shack part # 276-1661 is a 4 pack of 50v 6 Amp axial diodes for $2.99 and replaces the original perfectly.

And REMEMBER... diodes are directional

This post was edited by justalurker on Fri, Jul 5, 13 at 16:22

Just because a battery was brand new doesn't mean it was fully charged.

Sometimes a new battery is bad.

This post was edited by bill_kapaun on Fri, Jul 5, 13 at 20:14

A few years back I purchased a new battery and it started the tractor once and never again. brought it back and got another one. this time I checked that it had 12-13 volts on it when I installed it. It was fine after that. 1st battery had to be a dud.

NEVER buy a storage battery from any store that won't or can't load test it right in front of you unless wasting your time and gas money to return a defective battery doesn't matter to you.

Go home with a new battery that is GOOD.

Ditto, ditto and ditto again on JAL's new tractor battery advice...

I know this is an old post, but some of the responses are from people who have helped my greatly over the years so I will try here first.

Craftsman 917.256810: Briggs 28n707 0173-01

Problem is discharging battery. I condemned a battery last week and got a new one (luckily on warranty at RK). Put new battery in, started right up, and checked that I had charging voltage at the battery (13.6). We did our mowing with no incident, parked the mower, one week later it wouldn't start, or even try to start. Measured about 5 volts. I jumped it and proceeded with about an hours mowing. After parking I killed it and tried to restart. It gave a slight effort, voltage read 11.8. I did a test I found on youtube for parasitic draw on a car. I read 3.6 on the 200milliamp scale.

I think my diode may be bad?

How do I verify this? I have a diode setting on my VOM but don't know how to use it.

If I verify this is bad, would one of these work https://www.ebay.com/itm/5pcs-MCC-50V-6A-Current-Blocking-Rectifier-Diodes-Solar-Panel-Wind-276-1661/270706352002?epid=25022444064&hash=item3f075b1f82:g:qrsAAOSwrcRbbY31:sc:ShippingMethodStandard!47130!US!-1

Any advice tricks on the actual replacement?

Thanks in advance!

It would seem that it is charging to me and that the draw on the system drained your battery down. Your alternator line that has a diode in it is what converts the AC current out of the stator to DC. Either with your diode tester or ohmeter, put you leads on both ends of the diode, then reverse them. You will have continuity one way, but not the other. You could also do this test at the battery terminals: With the engine running, set your scale on DC and if the reading is more than the reading when it isn't running -it is charging. Repeat the test setting the scale on AC. Very little- less than 1 volt AC should be present. Excessive AC will indicate a failed diode. Briggs 393456 is the diode with the harness.

You can continue looking for your draw by hooking your meter or test light inline as you have been doing before, but know that your rider will have some draw present when it isn't running. If you are measuring 3.6 volts, that is a bit high. Ideally nothing to about 1 volt would be acceptable for equipment that is run every couple of weeks. You could unhook connectors one at a time, wiggle the key switch etc until you find the larger draw. Or unhook a battery terminal when the machine is not in use to eliminate the draw.

You might have a parasitic draw on the battery. Also check the stator for proper voltage output

All tractors have minute parasitic draw , nature of the beast . Proper stator charging rate is paramount , if diode is burnt you dead in the water as indicated previously .