2 wire alternator issue

[leeallen]

I have a two wire alternator on a ford 640. I do not have a key
switch but instead a simple push pull 2 post switch.
I believe the red wire from the alt. goes to the amp meter -where does the white from the alt. wire go? Thanks.
The way I have it wired right now everything operates fine except when i push the switch in with the tractor running the tractor keeps running. I have tested the switch and the alternator and they both are good. When the tractor is not running, the switch kills power.

 

[Sean in PA]

A 640 came from the factory with a generator, not an alternator, and a key switch and the starter button down on the transmission top plate. Since yours no longer has a key switch or a generator, we can only guess as to which alternator it might have and how the person that converted it might have wired it.

You say "The way I have it wired right now" makes me think that you've changed some things as well. Did you do the conversion from generator to alternator yourself? Did you replace the key switch with the push/pull switch yourself? If not, then what have you changed, and have the symptoms changed any when you made the change(s)?

Was everything working properly with the generator and the push/pull switch at some point in the past and then it stopped working correctly?

Your symptoms sound like you need a diode or a light bulb in line with one of the the alternator wires. Perhaps if you can draw up a diagram of how you have it wired now and post it here, someone might be able to tell you what might help.

 

[JMOR]

(quoted from post at 06:01:58 06/24/14) I have a two wire alternator on a ford 640. I do not have a key
switch but instead a simple push pull 2 post switch.
I believe the red wire from the alt. goes to the amp meter -where does the white from the alt. wire go? Thanks.
The way I have it wired right now everything operates fine except when i push the switch in with the tractor running the tractor keeps running. I have tested the switch and the alternator and they both are good. When the tractor is not running, the switch kills power.

ou can't expect decent answers to questions cast in wire colors. Any jake leg could select any wire color he wanted.

 

[rvirgil_KS]

A switch is simply a device to open and close a connection. from an electrical standpoint the circuit does not care if the switch is activated by a key or a toggle.

Do you have the common Delco 10SI alternator with output coming from big stud on the back and control via a 2 pin plug on the edge?

If so, the large output stud on back goes to ammeter, or if no ammeter to the start solenoid with the big cable from the battery. This may be a red wire

The connector plug for the 2 pin connector often has a white wire from #1 pin and a red wire from #2 pin.

Which red wire do you have connected to the ammeter?

Usually on a tractor the #2 wire simply loops down to the big output stud.

The #1 wire goes back to the output side of the ignition switch. This must have an isolating device in the line, usually either a diode or and indicator light. If this device is not present the alternator will continue to supply the ignition circuit when the switch is turned off and engine will continue to run.

Supply to the ignition and light switch come from alternator side of the ammeter.

 

[sunbeam]

The alternator is back feeding the ignition. It can be fixed with a diode in the white wire line

 

[souNdguy]

them wire colors mena little to us.

And if it is more than 1 wire.. it should be 3, not 2.

charge stud goes to one side of ammeter, other side of ammeter goes to hot side of start solenoid.

power for ignition and lights come off the side of the ammeter that the alt charge stud is hooked to. nothing else on the other side of the ammeter hooked to the battery.

now, the lil 2 terminal spade connectors ont he side of the alt. they are marked 1 and 2

make a short jumper with a fem spade and a ring terminal and jumper #2 to the charge stud.

now #1 needs to run thru an isolation device, in your case, i'd reccomend a 194 trailer lamp bulb, to the same side of the ignition switch as the coil is on.

you can buy trailer lamp bulbs in lil holders with wires on them for easy connection.

alternately, you could get a momentary button like a horn button, and hook one side to the power line to the coil, and the other to #1 and after you start her and get her to mid throttle, just push the horn button for a second, and she should start charging.

they way you have it wiured now, it sound slike #1 is hooked straight to coil power with no isolation, and is backfeeding the coil when you turn the ignition switch off.

 

[leeallen]

thank you sound guy

 

[leeallen]

Thanks, when I get back from vacation, I will.