# Short



## rolufs2500 (6 mo ago)

I have a 1971 MF135. When I try charging the battery with the cables attached it keeps kicking the charger off, when I take the cables off and try that way it charges fine. It is a positive ground tractor. Thanks for any help!


----------



## pogobill (Jan 31, 2012)

It is supposed to be a negative ground tractor.


https://www.tractordata.com/farm-tractors/000/7/4/743-massey-ferguson-135.html


I'm wondering if the positive battery cable is shorting to ground. Have you been having issues of the battery going dead when parked? I use a battery disconnect switch on my tractor to eliminate any issues with the battery.


----------



## rolufs2500 (6 mo ago)

It was a positive ground when I got it. Not sure how to change it.


----------



## pogobill (Jan 31, 2012)

rolufs2500 said:


> It was a positive ground when I got it. Not sure how to change it.


You may have to look into it further, but the cable ends are usually different so that you have difficulty hooking the negative tractor cable to the positive battery post. Here's some info.
Does the tractor have an alternator or a generator? Alternators are generally Negative ground, Generators are usually positive.... usually, not always.


https://www.qtponline.com/sites/admin/plugins/elfinder/files/qtp/Wiring%20Diagram%20(002).pdf


----------



## BinVa (Sep 21, 2020)

If you are attaching your charger leads correctly... and the battery cables are clean..tight..and shielding undamaged...2 things come to mind..a bad battery or voltage regulator/generator/alternator shorting to ground. B.


----------



## sixbales (May 18, 2011)

It might be that you actually have a short circuit somewhere? Track it down. Here's a picture of my old Ford 30 years ago, due to a short circuit. I fixed it up and it still runs great today. Pictured in my avatar.


----------



## rolufs2500 (6 mo ago)

pogobill said:


> You may have to look into it further, but the cable ends are usually different so that you have difficulty hooking the negative tractor cable to the positive battery post. Here's some info.
> Does the tractor have an alternator or a generator? Alternators are generally Negative ground, Generators are usually positive.... usually, not always.
> 
> 
> https://www.qtponline.com/sites/admin/plugins/elfinder/files/qtp/Wiring%20Diagram%20(002).pdf


It has a generator


----------



## BinVa (Sep 21, 2020)

Shorts are nothing to play with..


----------



## rolufs2500 (6 mo ago)

Dang!


----------



## sixbales (May 18, 2011)

Install a battery disconnect switch on your tractor. Disconnect the battery whenever you leave it. That protects your tractor while you are away from it,

Plus, if your tractor starts smoking profusely whilst you are using it, all you have to do is flick the battery disconnect switch and the smoke will stop (ask me how I know this).


----------



## BinVa (Sep 21, 2020)

sixbales said:


> Install a battery disconnect switch on your tractor. Disconnect the battery whenever you leave it. That protects your tractor while you are away from it,
> 
> Plus, if your tractor starts smoking profusely whilst you are using it, all you have to do is flick the battery disconnect switch and the smoke will stop (ask me how I know this).


Sixbales you’re right… there’s nothing worse then the smell of burning wires/oil and telltale sign of smoke..A disconnect switch is much easier solution than reaching for a wrench, and grabbing a red hot battery cable with 1 hand..while trying to put a fire out with the other….especially on the side of the road!! Some things do leave a lasting impression!!


----------



## rolufs2500 (6 mo ago)

Thanks guys for all the input and stories. The new coil fixed the problem. I am going to do the disconnect switch though, good idea! Will keep an eye on this forum to see what else I can learn, maybe even help someone else out.


----------



## Always something (6 mo ago)

rolufs2500 said:


> I have a 1971 MF135. When I try charging the battery with the cables attached it keeps kicking the charger off, when I take the cables off and try that way it charges fine. It is a positive ground tractor. Thanks for any help!


I have never seen 12 volt positive ground system tractor .Last positive ground I saw was a 8 volt system. My 71 135 is a positive ground .converted to alternator.You need to look up the tractor facts .If you are constantly having to charge the battery you system is all screwed up.Some how the polarity has been reversed.


----------



## Always something (6 mo ago)

rolufs2500 said:


> I have a 1971 MF135. When I try charging the battery with the cables attached it keeps kicking the charger off, when I take the cables off and try that way it charges fine. It is a positive ground tractor. Thanks for any help!


----------



## Always something (6 mo ago)




----------



## John Liebermann (Sep 17, 2018)

Always something said:


> I have never seen 12 volt positive ground system tractor .Last positive ground I saw was a 8 volt system. My 71 135 is a positive ground .converted to alternator.You need to look up the tractor facts .If you are constantly having to charge the battery you system is all screwed up.Some how the polarity has been reversed.


I agree,
This tractor needs to be completely diagnosed in my opinion. First, why would an ignition coil have anything to do with charging? Second a lead acid battery can be backward charged but I don't know how well it would work.

Something definitly not right here.


----------



## Busted Tractor (May 22, 2018)

Massey 135 have all been negative ground. if you have a constant draw on the battery you NEED to find out why. When the tractor is turned off the only place hooked to the battery is the switch and the charging circuit. Also some tractor have the light switch "live". 
To find what is drawing current disconnect individual circuits until the draw is gone. Places to check: Voltage regulator cut out stuck shut. Bad ignition or light switch, Wire rubbed thru in the harness or under the dash. No tools are really needed just a good eye when connecting the battery terminals.
One last though does the ammeter register a charge or discharge when the battery cable is touched to the battery post.
AND be aware the previous owner could have charged the battery backwards. If the battery was drained or almost completely it possible to charge them backwards
What ever you do don't leave the "magic smoke" out of the tractor, it is no fun trying to put it back in (repairing the damage).


----------



## Always something (6 mo ago)

John Liebermann said:


> I agree,
> This tractor needs to be completely diagnosed in my opinion. First, why would an ignition coil have anything to do with charging? Second a lead acid battery can be backward charged but I don't know how well it would work.
> 
> Something definitly not right here.


Did I say positive ground on mine ?that there is brain fart for sure I am running around in circles .Yes you can reverse polarity. Dead drain the battery
Start


Always something said:


> I have never seen 12 volt positive ground system tractor .Last positive ground I saw was a 8 volt system. My 71 135 is a positive ground .converted to alternator.You need to look up the tractor facts .If you are constantly having to charge the battery you system is all screwed up.Some how the polarity has been reversed.


Can't believe I said my 135 had a positive ground.


----------



## Always something (6 mo ago)

Busted Tractor said:


> Massey 135 have all been negative ground. if you have a constant draw on the battery you NEED to find out why. When the tractor is turned off the only place hooked to the battery is the switch and the charging circuit. Also some tractor have the light switch "live".
> To find what is drawing current disconnect individual circuits until the draw is gone. Places to check: Voltage regulator cut out stuck shut. Bad ignition or light switch, Wire rubbed thru in the harness or under the dash. No tools are really needed just a good eye when connecting the battery terminals.
> One last though does the ammeter register a charge or discharge when the battery cable is touched to the battery post.
> AND be aware the previous owner could have charged the battery backwards. If the battery was drained or almost completely it possible to charge them backwards
> What ever you do don't leave the "magic smoke" out of the tractor, it is no fun trying to put it back in (repairing the damage).


 0 amps in a battery to accomplish reverse polarity charging .Stone cold dead..I would add that if there is a amp meter. And if the system polarity has been reversed .it should not move or peg to discharge.Older regulators have contact points 
Every time it is operating these contact points are constantly opening and closing .And every time there is a spark.Burning out the contact over time..

The voltage regulator will go bad.It is just a guestion of when. Low battery amps make it happen faster.Since It works on electro magnets low amps are a killer.
.if you weld ,then it would be like trying to strike a arc when the amps are to low and the rod keeps sticking. The same thing is true for starters .So try never to try to start without a good charge in the battery.

.If if the engine starts runs but dies when the battery cable is removed while running .The generator or regulator orboth need service.


----------

