1966 Ford 3000 generator light stays on

I have searched this topic and almost all responses cease short of resolution. The long and the short of this situation is that I have replaced the wiring harness, voltage regulator, instrument cluster, battery, and generator. The aggravating thing is that generator light stays on all the time. It dims a little at higher rpm but never goes out. I've tested the gen output and it is strong. I've polarized the gen and voltage reg. The generator mounts were sanded to bare metal. The battery ground is bare metal. The oil light works fine as does the temp gauge. The transmission light works normally as do the headlights. The only gauge that is squirrely is the gas gauge. It bounces all over the place and reads empty sometimes. I have grounded that particular wire and it pegs to full. So the gauge at least seems fine. Don't know about the sender unit. Does the fuel sender have a dedicated ground or is the diesel tank the ground? I can push the contacts closed on the voltage regulator and the light goes out. I'm sorta at my wits end so any input would be greatly appreciated.l

my bet is on a dodgy vreg...

what volts on battery when running at high throttle, vs static when not running.

if you full field it when running what happens?

have you cleaned all the lil connectors that slip onto the vreg contacts? they can corode pretty badly and not make contact even when clipped on..

soundguy

(quoted from post at 09:38:25 10/09/11) my bet is on a dodgy vreg...

what volts on battery when running at high throttle, vs static when not running.

if you full field it when running what happens?

have you cleaned all the lil connectors that slip onto the vreg contacts? they can corode pretty badly and not make contact even when clipped on..

soundguy

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Everything including the vreg is brand new so all the contacts and connections are shiny. The volts when not running are right at 12.10v at the battery.(which is a new interstate 4LDT). When running idle or revving it stays about the same. The voltage may increase but not by much when running. Pardon my ignorance but what does full field mean? Also, does the fuel sender have a dedicated ground or does it ground thru the tank itself?

If the voltage does not come up appreciably.. it is not charging.

full field means applying bat power to the field tab on the genny. can't answer your gas gauge question..

soundguy

I'll chime in on this. Get yourself a single-wire alternator and throw away the gen/reg. You can spend hours and lots of $ trying to get that old crap to work. You can't rely on the VREG working, even if it's new. You can't rely on the so-called gen 'motor' test, because they can spin even if they're bad. Both of these Lucas components are so awful, you can never count on either of them. Makes trouble-shooting a nightmare.

I have a '66 3000. After I hooked up the 10si alt, I got a solid 14 volts at any speed. If you end up buying a replacement generator, just spend the same (or less) on a alternator.

(quoted from post at 18:40:50 10/08/11) I have searched this topic and almost all responses cease short of resolution. The long and the short of this situation is that I have replaced the wiring harness, voltage regulator, instrument cluster, battery, and generator. The aggravating thing is that generator light stays on all the time. It dims a little at higher rpm but never goes out. I've tested the gen output and it is strong. I've polarized the gen and voltage reg. The generator mounts were sanded to bare metal. The battery ground is bare metal. The oil light works fine as does the temp gauge. The transmission light works normally as do the headlights. The only gauge that is squirrely is the gas gauge. It bounces all over the place and reads empty sometimes. I have grounded that particular wire and it pegs to full. So the gauge at least seems fine. Don't know about the sender unit. Does the fuel sender have a dedicated ground or is the diesel tank the ground? I can push the contacts closed on the voltage regulator and the light goes out. I'm sorta at my wits end so any input would be greatly appreciated.l

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And there you have it. The classic Lucas generator/regulator. The one that never works right.
Experiences like this are exactly why I almost always suggest getting a Delco 10si or 10dn alt and firing the Lucas crap in the scrap bin.

At this point I guess you can full field the gen and see if it actually can produce something. If it can then likely you need another new regulator. If it can't... honestly... get the Delco alt and save yourself a lot of greif.

Rod

Could you give me the specifics of how to full field? Can you just run a jumper to the two posts on the generator? Also, how complicated is it to do the alternator conversion?

(quoted from post at 10:57:25 10/11/11) Could you give me the specifics of how to full field? Can you just run a jumper to the two posts on the generator? Also, how complicated is it to do the alternator conversion?

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ust jumper from generator FIELD terminal to hot/ungrounded battery post. If that still fails to increase battery voltage when running engine at speed, then add an [u:6a1e5e6d8d]additional[/u:6a1e5e6d8d] jumper from generator ARMATURE terminal to FIELD terminal and see if that raises battery voltage. Engine running at speed and allow at least a minute to see if battery voltage is coming up. With both jumpers, the VR is out of picture.

(quoted from post at 08:10:21 10/11/11)

(quoted from post at 10:57:25 10/11/11) Could you give me the specifics of how to full field? Can you just run a jumper to the two posts on the generator? Also, how complicated is it to do the alternator conversion?

Click to expand...

ust jumper from generator FIELD terminal to hot/ungrounded battery post. If that still fails to increase battery voltage when running engine at speed, then add an [u:5a3c76b6c0]additional[/u:5a3c76b6c0] jumper from generator ARMATURE terminal to FIELD terminal and see if that raises battery voltage. Engine running at speed and allow at least a minute to see if battery voltage is coming up. With both jumpers, the VR is out of picture.

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I did as you instructed (jumped from the FIELD terminal on the generator to the Ungrounded Hot post on the battery (+ Positive ?)) and it hissed and sparked with much fervor. I hope I didn't fry something. I jumped it for less than a second. Did I do something wrong or is this an indication of something else?

(quoted from post at 14:15:36 10/11/11)

(quoted from post at 08:10:21 10/11/11)

(quoted from post at 10:57:25 10/11/11) Could you give me the specifics of how to full field? Can you just run a jumper to the two posts on the generator? Also, how complicated is it to do the alternator conversion?

Click to expand...

ust jumper from generator FIELD terminal to hot/ungrounded battery post. If that still fails to increase battery voltage when running engine at speed, then add an [u:287eae2c40]additional[/u:287eae2c40] jumper from generator ARMATURE terminal to FIELD terminal and see if that raises battery voltage. Engine running at speed and allow at least a minute to see if battery voltage is coming up. With both jumpers, the VR is out of picture.

Click to expand...

I did as you instructed (jumped from the FIELD terminal on the generator to the Ungrounded Hot post on the battery (+ Positive ?)) and it hissed and sparked with much fervor. I hope I didn't fry something. I jumped it for less than a second. Did I do something wrong or is this an indication of something else?

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definitely suspect the "something else", as that generator field should only draw 2 amperes, which is less than a headlamp draw and should not result in "hissed and sparked with much fervor". Are you sure you got the Field terminal? If you jump to ARM terminal with engine stopped, you might see that result. You may have a short in the field wiring elsewhere. You can remove the wire from the generator Field terminal & tape it aside and try again......if same result, then I expect generator field has a problem.

Alternator conversion is more expensive than difficult. If the tractor is after '72 you can install the new style instruments with the tach drive coming off the oil pump drive... then throw a basic Delco 10si alt in place of the gen. The biggest part of that job is grinding out the holes in the lower bracket to fit the alt, then adapting a longer curved upper bracket... and a little jigging around to get the correct belt length as it takes a longer belt. Wiring requires a few little changes depending on how neat you wish to be. Last one I did... I just jumpered the BAT wires at the reg to eliminate the reg... and jumped the indicator light wire. Not a big job.

In your situation where you've already bought new instruments, presumably correct for your tractor's vintage... probably the best route is to find the Delco 10dn externally regulated alt (with tach drive) and the appropriate solid state reg that goes with... or I believe this site/Tisco supplies a Delco 10si conversion with a drive adapted to the 10si rotor. Seems to me that's going to run you about 350 bucks or so. 10dn should be cheaper... but I forget the Wilson part number you need. I think you might find it by application... for an AC 190 or something like that. Somebody sharp at the parts counter can probably find that alt with the tach drive.

Rod