8n alternator help


so mine has a platic cap where the excite and sense is on the picture so not really sure what to jump it to for that, ill double check the D hole but im pretty sure it has that
 
(quoted from post at 18:11:40 06/20/23)
so mine has a platic cap where the excite and sense is on the picture so not really sure what to jump it to for that, ill double check the D hole but im pretty sure it has that
ull the cap off of the spade lugs
 
(quoted from post at 17:17:05 06/20/23)
(quoted from post at 18:11:40 06/20/23)
so mine has a platic cap where the excite and sense is on the picture so not really sure what to jump it to for that, ill double check the D hole but im pretty sure it has that
ull the cap off of the spade lugs

Both lugs have same voltage as the batt stud , when battery is hooked up they both match battery.

Tried the D looking port also nothing changed
 

To deanostoybox point. How does the belt fit the other pulleys, not just the alternator pulley? I have seen people install a narrow belt to fit the alternator pulley when they do a conversion. The correct method is to install a pulley of the width of the existing belt, otherwise the narrow belt can bottom out in the wider pulleys and slip under load, even if it seems tight.
 
(quoted from post at 17:57:30 06/20/23)
To deanostoybox point. How does the belt fit the other pulleys, not just the alternator pulley? I have seen people install a narrow belt to fit the alternator pulley when they do a conversion. The correct method is to install a pulley of the width of the existing belt, otherwise the narrow belt can bottom out in the wider pulleys and slip under load, even if it seems tight.

It fits alt and fan pulley snug its hard to see down on the crank one
 
(quoted from post at 08:58:47 06/21/23)
(quoted from post at 17:57:30 06/20/23)
To deanostoybox point. How does the belt fit the other pulleys, not just the alternator pulley? I have seen people install a narrow belt to fit the alternator pulley when they do a conversion. The correct method is to install a pulley of the width of the existing belt, otherwise the narrow belt can bottom out in the wider pulleys and slip under load, even if it seems tight.

It fits alt and fan pulley snug its hard to see down on the crank one

A simple test, take a finger, screw driver are broom stick apply hard pressure on the alternator fan, try and move the alternator fan.

Does the pulley move/slip in the belt if so you have a issue with the belt are pulley.

One time one fought me the pulley was slipping on the alternator shaft. I will never forget that one : ( It ate my lunch.

If there is any good out of what I have read you can hear the alt wine that's always a good sign to me. That does not mean good are bad but good its turning on. I do not understand checking the alt with the battery disconnected so what does that prove?

That alt is so simple to diagnose STOP! and confirm the simple stuff.
 
(quoted from post at 17:46:53 06/20/23)
(quoted from post at 17:17:05 06/20/23)
(quoted from post at 18:11:40 06/20/23)
so mine has a platic cap where the excite and sense is on the picture so not really sure what to jump it to for that, ill double check the D hole but im pretty sure it has that
ull the cap off of the spade lugs

Both lugs have same voltage as the batt stud , when battery is hooked up they both match battery.

Tried the D looking port also nothing changed
With the battery connected tractor running take a jumper wire from the batt term on the alt. to the spade terminals you uncovered. Monitor voltage at the battery when you do this and see what if any changes happen.
 
(quoted from post at 04:36:21 06/21/23)
(quoted from post at 08:58:47 06/21/23)
(quoted from post at 17:57:30 06/20/23)
To deanostoybox point. How does the belt fit the other pulleys, not just the alternator pulley? I have seen people install a narrow belt to fit the alternator pulley when they do a conversion. The correct method is to install a pulley of the width of the existing belt, otherwise the narrow belt can bottom out in the wider pulleys and slip under load, even if it seems tight.

It fits alt and fan pulley snug its hard to see down on the crank one

A simple test, take a finger, screw driver are broom stick apply hard pressure on the alternator fan, try and move the alternator fan.

Does the pulley move/slip in the belt if so you have a issue with the belt are pulley.

One time one fought me the pulley was slipping on the alternator shaft. I will never forget that one : ( It ate my lunch.

If there is any good out of what I have read you can hear the alt wine that's always a good sign to me. That does not mean good are bad but good its turning on. I do not understand checking the alt with the battery disconnected so what does that prove?

That alt is so simple to diagnose STOP! and confirm the simple stuff.

with engine off i can get it to move however it takes a bit of force, and it does whine when running around the belt area
 
(quoted from post at 06:46:51 06/21/23)
(quoted from post at 17:46:53 06/20/23)
(quoted from post at 17:17:05 06/20/23)
(quoted from post at 18:11:40 06/20/23)
so mine has a platic cap where the excite and sense is on the picture so not really sure what to jump it to for that, ill double check the D hole but im pretty sure it has that
ull the cap off of the spade lugs

Both lugs have same voltage as the batt stud , when battery is hooked up they both match battery.

Tried the D looking port also nothing changed
With the battery connected tractor running take a jumper wire from the batt term on the alt. to the spade terminals you uncovered. Monitor voltage at the battery when you do this and see what if any changes happen.

i can try that for sure, should i do 1 at a time or both at same time. both those lugs are currently matching the Batt output post
 
(quoted from post at 10:48:04 06/21/23)
(quoted from post at 06:46:51 06/21/23)
(quoted from post at 17:46:53 06/20/23)
(quoted from post at 17:17:05 06/20/23)
(quoted from post at 18:11:40 06/20/23)
so mine has a platic cap where the excite and sense is on the picture so not really sure what to jump it to for that, ill double check the D hole but im pretty sure it has that
ull the cap off of the spade lugs

Both lugs have same voltage as the batt stud , when battery is hooked up they both match battery.

Tried the D looking port also nothing changed
With the battery connected tractor running take a jumper wire from the batt term on the alt. to the spade terminals you uncovered. Monitor voltage at the battery when you do this and see what if any changes happen.

i can try that for sure, should i do 1 at a time or both at same time. both those lugs are currently matching the Batt output post
oth at same time, & if that changes anything, then try each individually to see which is making a difference if any.
 
Disclaimer: What I think I know here I learned from Tim and Jesse. If I appear to disagree, it is probably a misunderstanding on my part.

It might help if there was a diagram showing the way to wire the aftermarket regulators. This is my understanding and I will try it on the new (much delayed) Sparex regulator that we picked up from NAPA thinking that we didn't have time for mail order... last October.
mvphoto106930.jpg


This is my attempt to gather the available information on the various generators in a table. If there is a (are some) mistake(s), let me know and I will correct it(them). Some of the amperage numbers came from different sources for instance. This was updated to correct the mistake on the Sparex equivalent part number.
mvphoto106931.jpg

The Sparex S.67125 regulator is for a later model (EDIT: 8N10001 20A generator with an 8N10505C regulator. Since Ford said to use the 8N10505B after removing the third brush per Service Bulletin 78, and both 8N10000B and 8N10001 are 20A generators, assuming I got that part right... it should be OK.)







This post was edited by Dave G9N on 06/22/2023 at 02:03 pm.
 
(quoted from post at 17:30:46 06/21/23) Disclaimer: What I think I know here I learned from Tim and Jesse. If I appear to disagree, it is probably a misunderstanding on my part.

It might help if there was a diagram showing the way to wire the aftermarket regulators. This is my understanding and I will try it on the new (much delayed) Sparex regulator that we picked up from NAPA thinking that we didn't have time for mail order... last October.
mvphoto106882.jpg


This is my attempt to gather the available information on the various generators in a table. If there is a (are some) mistake(s), let me know and I will correct it(them). Some of the amperage numbers came from different sources for instance.
mvphoto106883.jpg

The Sparex regulator is for a later model (NAA?) that should be compatible with the Rev B. The Sparex is intended for a higher output generator, but the 8N was apparently designed to run without a regulator other than the manual output adjustment so it can't put out enough current to hurt itself. Without a regulator and set for high output without using the lights the 8N genny may have been able to overcharge the battery. As I said, If Tim or Jesse say I am out to lunch, believe them.
think table looks good, but IF the Sparex reg is for the NAA, it is a B-ckt reg and the 8N required A-ckt.
 
(quoted from post at 20:18:46 06/21/23) Hooked battery to both tab and nothing changed, they both had power already
here are several one-wire regulators for 10 SI floating about the world and I have first hand experience with only one of those and this one has both spade lugs in common with BATT, so your findings are no surprise.
 
i think im going to toss a new belt on for good measure, its a older belt does have some cracks etc. next step is to take it off and find a alternator repair shop
 
(quoted from post at 10:02:17 06/22/23) i think im going to toss a new belt on for good measure, its a older belt does have some cracks etc. next step is to take it off and find a alternator repair shop
as already been discussed, but here is pulley/belt info courtesy of HOBO.
uiRscmZ.jpg
 

From you description of the belt being somewhat tight you should see more than battery voltage at the battery. Its a issue but I don't think the main issue you are having.

Crank the engine take a screwdriver and touch it to the rear of the rear bearing dose the bearing become magnetic. You can also do this to the end of the rotor shaft at the front. If it pulls/sticks the screwdriver to metal its trying to charge if not its not charging. This is a down and dirty test in the field with no test Equitment on hand to check and see if it will get you home.

When you grounded the regulator tab thru the D hole that bypassed the voltage regulator if it did not go full charge something is wrong with the alternator.

If it did go into full charge the regulator is bad. All my assumptions are for a 3 wire alt but the magnetic test should hold true for both.
 
(quoted from post at 04:37:43 06/22/23) I think table looks good, but IF the Sparex reg is for the NAA, it is a B-ckt reg and the 8N required A-ckt.
hanks, good catch. The Sparex S.67125 is listed in the catalog as equivalent to an 8N10505C.

The table has been updated and I replaced the one in the previous post with the correction.

I forgot to update the equivalent part number when I returned the S.6712[b:241cb7acbf]6[/b:241cb7acbf] that NAPA sent me the first time. It was for an NAA and was the B-ckt. If I remember correctly, you might have caught that before and saved me some trouble.

https://us.sparex.com/voltage-regulator-67125.html
"Voltage Regulator w/ Mounting Plate & Hardware Fits: 8N Replaces: 8N10505C"
 
Yesterday's Tractor Forums

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