New Battery going dead

[608KEB 795]

I bought a 1999 312-8 for my Dad. He put a new battery in about a month ago. The battery has went dead twice since.  He has only started the tractor  3-4 times during this period. I'm looking for some suggestions  as where to start looking  for the battery draining  culprit. 

Edited December 8, 2018 by 608KEB

[Digger 66 3,478]

If you have one of those bench-top battery chargers ( the kind with the ammeter on the front ) around , first thing I would do is disconnect the battery and clip the leads to the POS & NEG tractor wires . See if there's a draw on the ammeter with the key and all other accessories off .

 

[gwest_ca-(File Mod) 11,039]

Disconnect the negative (-) battery cable at the battery. Keep the key in the OFF position.

Connect at test light or voltmeter to the negative battery post and the cable you just removed.

If no short is present the light will not illuminate or a voltmeter will show 0 battery voltage.

If a short is present the light will illuminate or a voltmeter will show battery voltage.

Start disconnecting items one at a time and reconnect until you get the light out or 0 volts. When that happens you have found the problem circuit.

Let us know what you find.

 

Garry

[953 nut 55,155]

Be sure to look at the fuse holders and the wiring in that area, they are directly under the battery and subject to corrosion which can conduct electricity.

[squonk 41,051]

1 hour ago, gwest_ca said:

Disconnect the negative (-) battery cable at the battery. Keep the key in the OFF position.

Connect at test light or voltmeter to the negative battery post and the cable you just removed.

If no short is present the light will not illuminate or a voltmeter will show 0 battery voltage.

If a short is present the light will illuminate or a voltmeter will show battery voltage.

Start disconnecting items one at a time and reconnect until you get the light out or 0 volts. When that happens you have found the problem circuit.

Let us know what you find.

 

Garry

A voltmeter may not show anything. Anything over 50 milliamps draw is not deemed acceptable. So a hundred milliamps may not show up on a volt gauge. A low range ampmeter would be better or a DMM with a milliamp scale. Test lights usually do the trick providing there isn't too much surrounding light to see if the bulb is glowing. Test lights have a 9 volt bulb to show up better when testing 12 volt systems. 

[gwest_ca-(File Mod) 11,039]

A 1 milliamp draw will show full battery voltage on a voltmeter set to VOLTS because the meter is wired in series between the negative post and the negative battery cable and is measuring voltage. Not the conventional way to use a voltmeter but it works and you can not damage the meter using it this way.

 

Garry

[608KEB 795]

I'll get back with results soon.

[608KEB 795]

I have no volt meter on this tractor. I'll be trying to figure out what's wrong with the 312-8 soon.

[608KEB 795]

The battery shows 12.4 volts when tractor is not running. The tractor shows 13.6 volts from the battery when running at 3/4 to full throttle.

[WHX?? 48,813]

Sounds about right , any chance you have a bad battery out of the box? It has been known to happen.

[Digger 66 3,478]

17 minutes ago, 608KEB said:

The battery shows 12.4 volts when tractor is not running. The tractor shows 13.6 volts from the battery when running at 3/4 to full throttle.

 

 

As stated above , it sounds about right .

What does the battery show for voltage while cranking it over ?

Does it go below 10 volts ?

Even so ,13.6 volts being produced by the charging system should be enough to recover the load from cranking it to start . Assuming your mowing or something rather than starting and shutting it off repeatedly .

 

I also keep all my 12 volt toy's batteries on a Tender Jr. when not in use , so I probably ought to clam up now  

 

Edited December 7, 2018 by Digger 66

[stevasaurus 22,713]

If you do not find anything wrong, I offer this.  The key switch on my 857 is a little touchy, I have found my battery dead and then noticed that the key was not all the way in the off position.  Now that I know about the switch, I have not had another issue.  I double check that key when I turn it off now. 

[608KEB 795]

On 12/1/2018 at 3:04 AM, Digger 66 said:

If you have one of those bench-top battery chargers ( the kind with the ammeter on the front ) around , first thing I would do is disconnect the battery and clip the leads to the POS & NEG tractor wires . See if there's a draw on the ammeter with the key and all other accessories off .

 

 

[608KEB 795]

On 12/1/2018 at 3:04 AM, Digger 66 said:

If you have one of those bench-top battery chargers ( the kind with the ammeter on the front ) around , first thing I would do is disconnect the battery and clip the leads to the POS & NEG tractor wires . See if there's a draw on the ammeter with the key and all other accessories off .

 

You mean like this charger? 

[608KEB 795]

There's no draw

[608KEB 795]

On 12/1/2018 at 4:36 AM, gwest_ca said:

Disconnect the negative (-) battery cable at the battery. Keep the key in the OFF position.

Connect at test light or voltmeter to the negative battery post and the cable you just removed.

If no short is present the light will not illuminate or a voltmeter will show 0 battery voltage.

If a short is present the light will illuminate or a voltmeter will show battery voltage.

Start disconnecting items one at a time and reconnect until you get the light out or 0 volts. When that happens you have found the problem circuit.

Let us know what you find.

 

Garry

There is no short. Thanks for the help. I don't know why the new battery went dead. The battery reads 13.6 volts when running. I hope it doesn't happen to my Dad again. Head scratcher for sure!

[squonk 41,051]

39 minutes ago, 608KEB said:

There is no short. Thanks for the help. I don't know why the new battery went dead. The battery reads 13.6 volts when running. I hope it doesn't happen to my Dad again. Head scratcher for sure!

What are your voltmeter leads attached to in this picture?

[608KEB 795]

21 minutes ago, squonk said:

What are your voltmeter leads attached to in this picture?

I'm not talented enough  to take a picture and have the tester hooked up. I took the picture  after testing for a charge  loss!😆

[squonk 41,051]

If the battery goes dead again get a 12 volt test light and try the test again. I don't trust a volt meter wired in series.

Edited December 8, 2018 by squonk

[Digger 66 3,478]

14 hours ago, squonk said:

What are your voltmeter leads attached to in this picture?

 

I was wondering the same thing ^ 

A couple of alligator clips can be handy here .

I hope you had the red lead of the meter connected to the - battery post and the black meter lead connected to the chassis ground cable ( while it was disconnected of course ) .