Perplexing alternator problem

Greg1959

Well-known Member
Ford 860. NAPA 10SI alternator quit charging. Replaced with new on 10SI (213-4011). Started motor and no charge. Amp gauge shows discharge when lights are turned on. Also, amp gauge shows a little jump towards (+) 3 times and does not try again until I shut down motor and disconnect battery. Installed new diode(1N4003), silver line towards alternator, just in case old one went bad. Same problems persists. #1 spade goes to diode then on up to terminal block. #2 spade goes to battery post on back of alternator.

I wired it using john in la "hundred series 12 volt conversion" instructions. Everything worked until this problem showed up.
 
Try this. It would be sort of like jump starting the alternator. Run a wire from the + side of the battery to the diode the side that is hooked to the alternator. If it charges then you have a problem with you wire or diode. If it does not try the magnet test and see if you lay say a small nut on the center bushing area of the alternator if it sticks. If it does not stick it is not exciting so you may have a new bad alternator.
 
#1 thru diode to switched side of key.

maybee your ammeter is bad.

have you checked with a volt meter?


got battery installed negative ground?
 
: Run a wire from the + side of the battery to the diode the side that is hooked to the alternator. If it charges then you have a problem with you wire or diode."

Ran jumper...no charge.


"If it does not try the magnet test and see if you lay say a small nut on the center bushing area of the alternator if it sticks. If it does not stick it is not exciting so you may have a new bad alternator."

Nut- Does not stick.

Thanks
 
#1 thru diode to switched side of key.- yes

maybee your ammeter is bad.- I figured if it could show a discharge the it should be able to read when charging

have you checked with a volt meter? -Alternator, yes output at 1300rpm is 0.90 volts


got battery installed negative ground? -yes
 
If your voltmeter is only reading .90 volts at the back of the alternator then your battery connection to the alternator has been lost. If its reading .90 higher than battery voltage with it running then I miss understood. jstpa
 
....and further more, since those 10SI units used so many different regulator designs from different suppliers & over the many years, you never know what the output will do with battery disconnected. Some will run wide open, while others will yield no output.
 
I disconnected the battery line to see if alternator would produce charge. Sorry I did not clarify that.
 
(quoted from post at 16:11:32 05/08/13) I disconnected the battery line to see if alternator would produce charge. Sorry I did not clarify that.
.....which may have killed it, if it was previously good alt. These alts can produce over a hundred volts when receiving full field and no or even moderate loads. Should never be run with battery disconnected.
 
What is a 'safe' way of checking one? If I need to do so in the future. BTW, I had called NAPA when this all started and asked if they had a way to test the alternator. Their response was "No, that machine has been broken for years."
 
(quoted from post at 16:31:36 05/08/13) What is a 'safe' way of checking one? If I need to do so in the future. BTW, I had called NAPA when this all started and asked if they had a way to test the alternator. Their response was "No, that machine has been broken for years."
ind another parts supplier. You can connect a voltmeter directly across the battery. If vehicle hasn't been run recently, the voltage will be approximately 12.3 volts. Then you start it, run at speed for a few minutes as you watch the voltage on your voltmeter climb a volt or more. No climb = no alternator output.
 
I did that at the onset of problem. Voltage read 12.38 from battery without tractor running. After starting, checked voltage at battery post on alternator. Still read 12.38 volts.
 
(quoted from post at 17:13:48 05/08/13) I did that at the onset of problem. Voltage read 12.38 from battery without tractor running. After starting, checked voltage at battery post on alternator. Still read 12.38 volts.
No climb = no alternator output. Alt not working.
You can do another test, but unless you are just curious or want to dig into the alt internals, it isn't worth much. It tells you whether the problem is the VR or some other area of the alternator. On the back side of alt is a "D" shaped hole. Inside that hole is a small metal tab. When a screwdriver is inserted & touches tab, it shorts that tab to the side of the "D" hole and this will provide full field current and if all else is well the alternator will output its maximum.
 
Sounds like you got a bad alternator right out of the box. I learned years ago to have them test them before I go out the door. Had more then one alternator and starter be bad from the get go
 
I believe it is a bad alternator. Thanks. Bad thing is...it's a 40-45 minute drive (one-way) to NAPA.
 
Pulling a battery cable off to check for an alternator charging is a way if you mess up to get your self very DEAD.
Only safe way to check an alternator is this.
#1 check battery voltage with it not running you should read 12.4 volts give or take a tad bit with a volt meter.
#2 start it up and run it say 1500 RPM and check voltage again. You should if it is working read around 13-14 volts.
When you unhook the battery with the engine running if the alternator is working it will see a dead battery and try to put out max volts which in turn will fry the VR so it will put out 90 plus volts at 35 plus amps and it takes on millionth of an amp to kill a man for that is like more then 35 million times more then it takes to kill you. That by the way is what the Navy E.T. schools teach
 
(quoted from post at 18:11:10 05/08/13) Pulling a battery cable off to check for an alternator charging is a way if you mess up to get your self very DEAD.
Only safe way to check an alternator is this.
#1 check battery voltage with it not running you should read 12.4 volts give or take a tad bit with a volt meter.
#2 start it up and run it say 1500 RPM and check voltage again. You should if it is working read around 13-14 volts.
When you unhook the battery with the engine running if the alternator is working it will see a dead battery and try to put out max volts which in turn will fry the VR so it will put out 90 plus volts at 35 plus amps and it takes on millionth of an amp to kill a man for that is like more then 35 million times more then it takes to kill you. That by the way is what the Navy E.T. schools teach
Old, "When you unhook the battery with the engine running if the alternator is working it will see a dead battery and try to put out max volts ..."------max [u:bc349d3556]OR nothing[/u:bc349d3556], as I already told Greg. Depends on the specific VR installed! I have some of each & if you ever saw the circuitry it is very clear as to the differences & how each behaves. Also easy to demonstrate.
 
Ya know how that is. That is one reason to bench test it before going out the door if they can do it that is
 
Yes one smoke test one way and some another way either way is not a safe or good idea to try for more then one reason the $$ it may cost you or your life
 
What I would do if I were you... start by hooking a ground wire from the alt case to some point on the engine block or mount so you know the alt has good ground. Then take a #4 wire from the BAT post directly to the Bat+ side of the starter relay so you know you have a direct connection to the battery. Make sure #2 is hooked back to the BAT on the alt and #1 is supplied battery voltage through the key or jumper or whatever so it's excited. When this is all done... start the engine and rev it to 2000 rpm or so... thus you know it should be charging. If it doesn't make 14+ V at the battery, get another alternator. If it's warranty... probably don't discuss this so much. Just install the new one as stated above.
For my own part I'd much rather see the exciter wire run through a 194 bulb from the key. Then you have a charge indicator light. Voltage is really the only measure that counts with alternators...
If you want to rehook the ammeter after all is known to be working... I would suggest you make sure and have at minimum a 60 amp meter... and wire it such that all of the tractor's electrical loads other than the starter are run through the ammeter... so one side of it is the main electrical terminus (including the alternator's BAT wire) and the other side goes directly to the battery pos at the starter relay.

Rod
 
Rod

Ground is good. Everything else was done as you stated except for the 194 bulb. AMP meter is 60 amp. I beg to differ on the 2000 rpm revs. That seems kind of high.

I appreciate your advice.
 
It should charge at a lot less than 2000 rpm... but without knowing what you've got on it for a pulley... I say 2K to be certain. Some will charge at 800. Some less if they've been setup with a low cut in.
If all has been done and it still won't charge, replace it.
Just the same... I'm not a big believer in the idea that 2 have now burned out for no reason... Make sure there isn't something grounding out and making smoke somewhere else in the system. That WILL fry the reg... sometimes.

Rod
 
(quoted from post at 04:35:07 05/09/13) Rod

Ground is good. Everything else was done as you stated except for the 194 bulb. AMP meter is 60 amp. I beg to differ on the 2000 rpm revs. That seems kind of high.

I appreciate your advice.

Unless you think its cool to run a amp meter I would ditch it and install a voltmeter,,, as you can see the amp reading was of little value VOLTS were..

One posted just muddied the water you can not be all over the place the voltage range is not variable (like 13 to 14V)... All your testing needs to be done with a know good fully charged battery ( that includes the battery in your tester volt meter)...

You can test the grounds and every connection by doing a voltage drop test...
 
that is probably what killed the alt.

when i saw .9v onthe alt output I knew you had puleld bat connection off.


why people think it's OK to unload a device like that is beyond me.

the old pull a bat cable to see if it stays running it like beating a crying child till it is no longer able to cry.

it MAY work.. and is a HORRIBLE way to go about things.. :(
 
(quoted from post at 18:11:10 05/08/13) it takes on millionth of an amp to kill a man

I agree with you that an unloaded alternator can create very dangerous currents, but a millionth of an amp will not kill a person. You have more than a millionth of an amp coursing through your body constantly, generated by your own nervous system. You only begin to feel anything in the way of a mild tingling at abut a thousandth of an amp.

Deadly current starts at about 1/10th of an amp minimum, and can be higher depending on which part of your body it is flowing through. 1/10th of an amp or higher directly across the heart is usually fatal. But while a full amp across your hand from one finger to another hurts like the dickens, and if it goes for long enough can cause burns, it will not kill you. Some folks have survived lightning strikes where thousands of amps have gone through parts of their bodies for a split second but they survived.

I am not saying to not be careful, just saying that a millionth of an amp is not what you should be worrying about.
 
Hey this is as per the U.S. Navy E.T. school in Damneck VA and they teach that 1 millionth of an amp can and will kill a person and I could see how if you have it hit you just right but either way I am just posting what the Navy teaches if not right take it up with the U.S.Navy and tell them they are not teaching things correctly
 
As some of you stated...Check connections.

The #1 wire going into the back of the 2 prong clip that connects to the alternator was not making a good connection onto the female spade connector. I cut the 2 prong clip out and replaced with insulated 1/4" female connectors. Started tractor and amps went to positive and started charging battery.

Thanks guys for all of your help.
 
(quoted from post at 12:05:47 05/09/13) As some of you stated...Check connections.

The #1 wire going into the back of the 2 prong clip that connects to the alternator was not making a good connection onto the female spade connector. I cut the 2 prong clip out and replaced with insulated 1/4" female connectors. Started tractor and amps went to positive and started charging battery.

Thanks guys for all of your help.
ld is going to be disappointed that you didn't blow up alternator or electrocute yourself! Just kidding! :twisted:
 
(quoted from post at 20:05:47 05/09/13) As some of you stated...Check connections.

The #1 wire going into the back of the 2 prong clip that connects to the alternator was not making a good connection onto the female spade connector. I cut the 2 prong clip out and replaced with insulated 1/4" female connectors. Started tractor and amps went to positive and started charging battery.

Thanks guys for all of your help.

Good you found it,,, I don't know why tractor folk are not willing to learn how to perform a voltage drop test,,, its like magic were NUTTIN else but luck would find issues like yours...

The biggest hurdled to over come is 1) the circuit has to have a load on it...
 
HOBO

Please explain to me how to perform a 'voltage drop test' so I'll know that info the next time I might encounter a similar problem.

Thanks
 
All you have to do is google it...

1) the circuit has to have a load on it even if you have to make up a load like using the circuit to power are ground a head light bulb... Voltage drop is the voltage loss in a circuit such as your bad connection at yer alt... Its quick and simple and efficient... I will take luck tho :D

The most common place you will see voltage drops issues are battery connections ( I am sure we have all see this and gonna run into it again)....

Voltage drop can be used on either side positive are negative,,, lets say you put one end of yer meter on the battery positive post and the other on the battery cable end at the bat pluss post,,, you will see 0V's,,, activate the starter and you see 12V's,,, that means you are loosing (dropping) 12V thru the connection,,, its a bad connection the same applies to the ground side... if you do not see a drop on the plus side move to the negative side and repeat the test,,, if you do not have a drop then test from the bat to the load at every connection.... If a FAST way to confirm power and grounds once you get a handle on it...

the longer the circuit is their will be some voltage drop but it would be in the 10's of a volt like .010V.... Google it their lost of info on you tube...

I am self taught and a slow learner I can not blame any info I have posted to be correct are blame anyone else... :lol:
 
Old-"Try this. It would be sort of like jump starting the alternator. Run a wire from the + side of the battery to the diode the side that is hooked to the alternator. If it charges then you have a problem with you wire or diode"

You were right. Although,I ran the jumper to the quick connect instead of the #1 spade on the alternator. I still had the 2 prong wire clip in the loop. This explains why it did not work.

Thanks
 
(quoted from post at 03:33:06 05/10/13) Always happy to help if and when I can
lso explains why he has a newer , more modern VR that outputs near ZERO when disconnected instead of a "deadly" voltage!!! :p
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top