farmall charging

[bill54]

I have a Farmall M converted to 12 volt system. It's not charging . I'm probably going to get another alternator but I'd like to know one thing (or two) . The amp gauge is the original and is broken . Don't know when it broke but sine it's been broke thats when I noticed I wasn't getting a charge .Could that be my problem ?I've been told I should have a volt gauge instead. I guess my main ? is will the system work with a bad amp gauge ?

 

[Clint S]

Yes on my 200 the amp gauge is broken and it charges. What kind of alt do you have. If it has an exciter coil that needs to get power too, BUT if left with power the whole time will draw your battery down. If feasible most folks use a 1 wire alt. I just installed a battery cut out switch I throw every time I get off.

 

[bill54]

Yes on my 200 the amp gauge is broken and it charges. What kind of alt do you have. If it has an exciter coil that needs to get power too, BUT if left with power the whole time will draw your battery down. If feasible most folks use a 1 wire alt. I just installed a battery cut out switch I throw every time I get off.

I don't know I assume its a GM type. Mechanically I can fix about anything but, when it comes to simple wiring like your talking about I get kinda simple myself .

 

[Clint S]

How many wires to the alt? A plug with 2 and a battery post.

Bat post to Battery

#1 spade is exciter needs 12 v with key on or most folks run a 1 way diode on this wire to stop battery drain and wire it hot. I just use a battery cut off.

#2 spade is the wire IIRC that sends voltage to the internal regulator so it can track voltage

 

[Soundguy]

whoever told you that you need a volt meter .. that advice makes me wonder.

center 0 ammeter tells you mUCH more about the health of a charge system. bat AND genny/alternator.

if the ammeter broke and is OPEN.. you won't get charge. if it is a 2 post ammeter.. jump the posts and see if charge comes back.

 

[Clint S]

SG that makes sense. The Ammeter is wired in series if you wire the alt through the Ammeter and it is broken open it will not charge. I guess on my tractor even though the Ammeter is broken I am still closed the needle moves a little OR it is the way I wired it it. I just used a volt meter and my knowledge about the GM alt to figure out a way to wire it so it charged.

 

[Soundguy]

not that a voltmeter is bad.. it just tells you very little compaired to am ammeter.

having both would be nice if you had the dash slot.

using a charge indicator lamp vs the diode is noce too.. lets you know when the alt turns on.. also can alert you to a discharge.. etc.. classic idiot lamp..

 

[bill54]

SG that makes sense. The Ammeter is wired in series if you wire the alt through the Ammeter and it is broken open it will not charge. I guess on my tractor even though the Ammeter is broken I am still closed the needle moves a little OR it is the way I wired it it. I just used a volt meter and my knowledge about the GM alt to figure out a way to wire it so it charged.

MY ammeter is broke, in that I can tap it and the needle just rattles around . It wasn't that way when it did charge, in fact it worked as it should' . I'll dheck tomorrow but, its pretty cold out there right now. I'll let you know how things turn out . and THANK YOU !

 

[Soundguy]

MY ammeter is broke, in that I can tap it and the needle just rattles around . It wasn't that way when it did charge, in fact it worked as it should' . I'll dheck tomorrow but, its pretty cold out there right now. I'll let you know how things turn out . and THANK YOU !

remember.. there are 2 basic ammeter types.

straight inductive ( clamp or loop style.. ) no break in the wire.. cable passes thru a loop or sleeve pickup.

shunt-voltmeter : current passes thru a shunt ( aluminum block, etc.. ), and the super small v-drop is measured adn displayed on a calibrated amp scale.

the meter needle action can be broke.. and the meter pass current.. or if the shunt or the connections open.. you are SOL...

remember.. straight voltmeters are parallel devices..

ammeters are serial devices..