Battery keeps discharging

JW!

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My Craftsman lawn mower kills the battery if it sits for a week. The battery is charged up but for some reason it is discharged after sitting idle and the battery is brand new. Any idea what could be causing the short?
 

sgkent

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start with the battery. How old is it? How many times has it fallen to a zero charge in its life?
 

sgkent

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then I would put an amp meter on it and see what the parasitic drain is. It could be a bad diode in the charging system, or a bad relay. Need to post a wiring diagram for it or model and serial if anyone is to give much more help than this generic suggestion.
 

Scrubcadet10

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Post the model number of the tractor. Should be on a tag under the seat. And start with 917.
 

bertsmobile1

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Usual culprit will be the diodes in the rectifier failing open circuit
Pull the connector apart at night in the dark.
If you get a nice big spark you have found the problem.
To confirm it either check the rectifier or just leave it unpluged for the week.
If the battery is fine then replace the rectifier .
The other thing that can drain the battery over a week is the carb solenoid.
Easy way to check that is to touch it first thing in the morning
If it is warm, it is energised .
 

JW!

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My mechanic neighbour suggested I pull the key out of the ignition, and that solved the problem, battery was fine the next week. So now I will leave the key out of the lawn mower, I don't think I will buy another ignition switch.
 

StarTech

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My mechanic neighbour suggested I pull the key out of the ignition, and that solved the problem, battery was fine the next week. So now I will leave the key out of the lawn mower, I don't think I will buy another ignition switch.
That tells me that you were leaving the switch on.
 

shinkle

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My mechanic neighbour suggested I pull the key out of the ignition, and that solved the problem, battery was fine the next week. So now I will leave the key out of the lawn mower, I don't think I will buy another ignition switch.
I had a previous mower doing the same thing. Somehow the switches go bad and allow a connection and battery drain. You can buy a replacement switch and new key for about $30, easy plug and play replacement.
 

Jinglepaws2

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My Craftsman lawn mower kills the battery if it sits for a week. The battery is charged up but for some reason it is discharged after sitting idle and the battery is brand new. Any idea what could be causing the short?
I, too, have a Craftsman rider mower purchased in 2016 that started doing that after 2 or 3 seasons. I purchased a new battery just like you and still had the same problem in a couple of months. (BTW,, I never left the key in the ignition.) I ended up getting a Battery Tender with a quick connect ring connector. Now I just plug it in whenever it's not in use. I never had that problem with the previous Craftsman I had for 12 years.

Craftman riders are now junk. In the first couple of seasons with light use with my current Craftsman, I had to replace a fan belt as well as a tire. Just last year, I had to replace the ignition switch because the reverse mow function broke. Even after 12 years, I never had to replace any of that on my old Craftsman. There's plastic where metal obviously needs to be. It built to have the shortest service life possible. When I have to replace my current Craftsman ( I seriously doubt it will last anywhere close to 12 years) I certainly won't be purchasing another Craftsman, that's for darn sure. Craftsman use to mean true quality but no longer.
 
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