I have an older PT-1425, with 25hp Kohler, whose battery loses voltage when turned off and at rest slowly from a full charge. I can read about 23 milliamps current draw with the key removed. I disconnected the rectifier in case a diode or something caused it, but that didn't change the current draw. (The charging system and stator look fine, and it charges at about 14.6V when running.) What is strange is that the voltage seems to drop to about 12.25 volts over a couple of days and then drops only super slowly after that. If the battery is disconnected completely, it maintains 12.70 Volts over time. (This is a new battery.) Could it be a "mild" short somewhere? Unlike a car with a parasitic draw, I am not sure there are a lot of fuses to pull to find the circuit to focus on (or are there?). I wish I had a wiring diagram, too. Any recommendation on what to do next? (I will put on a battery post switch to disconnect the battery when the tractor is not being used as a workaround, but I am really wondering what the root cause is.) Thanks in advance.
Older PT-1425 with parasitic battery draw - not sure where to look
- Thread starter gd2141
- Start date
-
- Tags
- battery parasitic draw pt1425
ponytug
Super Member
Welcome to TBN!
Sorry to hear this. Ugh. I hate chasing tiny current draws, because they are such pain to find.
Option one: put a battery disconnect in, and forget it.
Option two: start by pulling the fuses in the main fuse box. (Remember to act surprised when the draw persists after pulling all the fuses.)
I tend to get a little compulsive about tightening every switch and wire connection, there are a bunch of wire connects behind the dash. Don't forget switches can leak current across them, even when off.
Good luck.
All the best,
Peter
Sorry to hear this. Ugh. I hate chasing tiny current draws, because they are such pain to find.
Option one: put a battery disconnect in, and forget it.
Option two: start by pulling the fuses in the main fuse box. (Remember to act surprised when the draw persists after pulling all the fuses.)
I tend to get a little compulsive about tightening every switch and wire connection, there are a bunch of wire connects behind the dash. Don't forget switches can leak current across them, even when off.Good luck.
All the best,
Peter
Roadworthy
Elite Member
Twenty three milliamps is not very much draw. Are you SURE of that reading? That's about what a single LED would draw. At that rate it would take quite awhile to drain the battery. You could start troubleshooting by disconnecting the power to the ignition switch. Most circuits go through there but not necessarily everything. Is your PTO manual or electric? I don't know how your alternator is wired. You can have a leaky component there and still put out charge voltage. Of course an external disconnect switch is an easy fix.
MossRoad
Super Moderator
- Joined
- Aug 31, 2001
- Messages
- 60,184
- Location
- South Bend, Indiana (near)
- Tractor
- Power Trac PT425 2001 Model Year
Welcome to TBN! 
m5040
Platinum Member
- Joined
- Nov 23, 2008
- Messages
- 893
- Location
- CT
- Tractor
- Kubota M6040 L2250, JohnDeere 310D, Ford 841 Elenco, Ford 961, Trapmaster, PT180 w/LM bucket and 45" brush cutter, PT1430 Deutz w/grapple bucket, Antonio Carraro Tigrecar 6500. John Deere 5300. Former owned Steiner 430 max, Goldoni REV Maxter 7
If the top of the battery is dirty with acid haze, it will draw down the battery.
Thinking I like your option one at the moment but will pull the dash and examine things (though maybe after the disconnect is installed and I have the time to focus on it). Thanks for your response!Welcome to TBN!
Sorry to hear this. Ugh. I hate chasing tiny current draws, because they are such pain to find.
Option one: put a battery disconnect in, and forget it.
Option two: start by pulling the fuses in the main fuse box. (Remember to act surprised when the draw persists after pulling all the fuses.)
Good luck.
All the best,
Peter
0.023 A is the reading, so hope I am reading it correctly. I know for a car that is a typical draw when off. It does take 5-6 days for the battery to drop to 12.2 from 12.7. That battery is new, so maybe I take it back for a load test...? I will open the dash and disconnect the power to the ignition switch to see if gives more clues. The PTO is manual.
The alternator is a stator-based one with magnets on the flywheel, generating AC going into a rectifier with DC to the battery. The system has the draw still when removing the rectifier completely (from the battery and from the stator).
Yes, think I will go with the external disconnect first and continue the diagnosing as time permits. Thanks for your reply
I will clean it and see if it makes a difference. I will say though, that the battery seems to hold a full charge when disconnected. Thank you!
jaxs
Elite Member
Hello gd2141,long time no see. So long in fact people are greeting you as if you were a stranger.
Your conversion is correct, 0.023 = 23 Ma
Having the battery load tested before tearing into it might be a good idea since it isn't uncommon for a battery to take a "surface charge" that doesn't last long.
Your conversion is correct, 0.023 = 23 Ma
Having the battery load tested before tearing into it might be a good idea since it isn't uncommon for a battery to take a "surface charge" that doesn't last long.
BobRip
Elite Member
I keep a battery maintainer on my 422. This covers losses from battery internal losses as well.