What is going on here? I've seen high voltage on the cts monitor after startup a few times. I've also seen it randomly on the highway well into the trip. I'm waiting on Nations' tech to get back to me and need the truck on Monday.
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Bad regulator on new Leece Neville alternator?
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What is going on here? I've seen high voltage on the cts monitor after startup a few times. I've also seen it randomly on the highway well into the trip. I'm waiting on Nations' tech to get back to me and need the truck on Monday.
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Do you know these posts?
I am also looking for a larger generator, but apparently these are prone to failure
Leece Neville voltage fluctuations - Ford Truck Enthusiasts Forums
6.0L Power Stroke Diesel - Leece Neville voltage fluctuations - It looks like I've joined a club I didn't know existed. The first time I started my Excursion after installing a new L-N alternator, I was surprised by the fluctuating RPMs and headlights. It settled down after 30-45 seconds and...
www.ford-trucks.com
I am also looking for a larger generator, but apparently these are prone to failure
A 15.8 voltage, not acceptable. That's an excessive voltage even for a Leece-Neville. However, they typically output a voltage that exceeds the voltage limit of the GPCM, which will cause fluctuations as the GPCM and alternator play tug of war over this threshold.
That is not constant, however. Mine will vary depending on the load due to battery replenishment loads, rpm, and a host of other things. For me, there are times of the year when it's fine, or I can overdrive the alternator with a smaller pulley that keeps the voltage up and GPCM off until the batteries take enough charge to lower the current output. It's a weird dance that would not occur if the voltage regulator met the spec that L-N states in the product brochure.
I am a little concerned about Nations as an L-N supplier, though.
As for Hartwig's comment that the L-N is prone to failure, I would disagree with that. They are pretty robust. The copies of the L-N, which look exactly alike and sold for a lower price, which Nations also sells, are not as robust.
That's a long thread; I'll post the work I did and made into a video.
That is not constant, however. Mine will vary depending on the load due to battery replenishment loads, rpm, and a host of other things. For me, there are times of the year when it's fine, or I can overdrive the alternator with a smaller pulley that keeps the voltage up and GPCM off until the batteries take enough charge to lower the current output. It's a weird dance that would not occur if the voltage regulator met the spec that L-N states in the product brochure.
I am a little concerned about Nations as an L-N supplier, though.
As for Hartwig's comment that the L-N is prone to failure, I would disagree with that. They are pretty robust. The copies of the L-N, which look exactly alike and sold for a lower price, which Nations also sells, are not as robust.
That's a long thread; I'll post the work I did and made into a video.
I just posted on another forum I replaced my regulator on my 4 year old LN just because I wanted new brushes
the new regulator surged so bad at start up in both voltage and RPM I had to put the old one back in
both should have had the same set point.
I have an email into Nations telling them the scenario and asking them if they have any suggestions or if I can just swap brushes on these sealed regulators
I agree the LN is a stout alternator used in many OEM applications I have no doubt it is the regulator that has changed
recently my original LN had 0 overvoltage fluctuation issues neither did my old OEM or even DC power 190
the new regulator surged so bad at start up in both voltage and RPM I had to put the old one back in
both should have had the same set point.
I have an email into Nations telling them the scenario and asking them if they have any suggestions or if I can just swap brushes on these sealed regulators
I agree the LN is a stout alternator used in many OEM applications I have no doubt it is the regulator that has changed
recently my original LN had 0 overvoltage fluctuation issues neither did my old OEM or even DC power 190
the L/N used to be decent and was affordable at 100 less than the mechman
but it seems like they decided to save a nickle that will cost them a dollar
a remote adjustable regulator would be a nice aftermarket item
but it seems like they decided to save a nickle that will cost them a dollar
a remote adjustable regulator would be a nice aftermarket item
set point is 14.2 or 14.4 for the literature i have seen ( not sure what one is accurate? ) and the regulator only had 14 v marked
my aftermarket transpoo part was supposed to be 14.4 but only had 12v marked on it
this L/N is a self excite alternator
my aftermarket transpoo part was supposed to be 14.4 but only had 12v marked on it
this L/N is a self excite alternator
When I was talking with the Prestolite tech rep he asked me to move the sense wire around, he didn’t understand why it was connected half way down to the battery, at the fusible link split. I think Ford did it to minimize output if the links blew. The first change he asked to try was to bring sense right to the power output terminal - no change.
He also asked if I could move sense to the drivers battery - no change.
14.5v at the GPCM kicks it off. Another division of my old company made the GPCM. I.ve watched 14.48v be fine.
Whenever I get this engine back in, I was going to try an underdrive pulley with a longer belt. Or every damn regulator that fits.
As I’ve said in the video, it happens with me only with a set of conditions, battery condition and their temp are the biggest factor, the acceptance rate of the batteries. However, it really is the voltage regulator. A slower ramp would help.
My workaround is just giving it more to do. At cold start I flip the HVAC blower to max, the extra amp load keeps a lower voltage threshold.
He also asked if I could move sense to the drivers battery - no change.
14.5v at the GPCM kicks it off. Another division of my old company made the GPCM. I.ve watched 14.48v be fine.
Whenever I get this engine back in, I was going to try an underdrive pulley with a longer belt. Or every damn regulator that fits.
As I’ve said in the video, it happens with me only with a set of conditions, battery condition and their temp are the biggest factor, the acceptance rate of the batteries. However, it really is the voltage regulator. A slower ramp would help.
My workaround is just giving it more to do. At cold start I flip the HVAC blower to max, the extra amp load keeps a lower voltage threshold.
Why don't you guys just give up in the Leece-Neville? Jacks still playing around with the blower motor, z-mans trying to build a regulator out of half old and new. Its old inefficient technology and will probably last forever. When you've had enough of it getcha the hairpin, its what the 6.0 needs.
For me, it's 30 seconds of an occasional issue at certain cold starts. Never a concern starting afterward and from then on, no issues of voltage. In fact, really good voltage and tracking my battery life and age resistance, the batteries are better for it as they would be with a hairpin.
One solution for some is to put on the overdrive pulley and just let it go high voltage and kick off the GPCM. It works well too, but not an absolute. For me, the issue is certainly not worth another alternator expenditure.
But once I learned my conditions, I use the fan, otherwise not. When I first installed this alternator, I never noticed an issue. It wasn't until my batteries got to a certain age - developed higher internal resistance.
To me, the most bothersome aspect is some people get hyper about it, and Prestolite is not accurate in their literature, or maybe they were before a Chinese company bought them. Some production components are out of China.
The bigger issue today is the quality of aftermarket replacement regulators is so poor. Confirmed by my asking a business that still rebuilds alternators and starters, a dying breed. And why so many of the parts store alternators are crap, they are rebuilt with crap parts. I used to walk up to a Ford counter and buy a voltage regulator, no more.
Two of my alternator testing graphs show the kick-out; stock, and overdrive pulley.
![771574]( "771574")
![771573]( "771573")
One solution for some is to put on the overdrive pulley and just let it go high voltage and kick off the GPCM. It works well too, but not an absolute. For me, the issue is certainly not worth another alternator expenditure.
But once I learned my conditions, I use the fan, otherwise not. When I first installed this alternator, I never noticed an issue. It wasn't until my batteries got to a certain age - developed higher internal resistance.
To me, the most bothersome aspect is some people get hyper about it, and Prestolite is not accurate in their literature, or maybe they were before a Chinese company bought them. Some production components are out of China.
The bigger issue today is the quality of aftermarket replacement regulators is so poor. Confirmed by my asking a business that still rebuilds alternators and starters, a dying breed. And why so many of the parts store alternators are crap, they are rebuilt with crap parts. I used to walk up to a Ford counter and buy a voltage regulator, no more.
Two of my alternator testing graphs show the kick-out; stock, and overdrive pulley.
My 230 amp LN. That is NOT normal wear.
Local suppliers tell me 6 months for replacement rotor/end housing with bearing.
This alternator always ran 14.2v and higher.
Don't know if I would buy again - looking for alternatives.
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Local suppliers tell me 6 months for replacement rotor/end housing with bearing.
This alternator always ran 14.2v and higher.
Don't know if I would buy again - looking for alternatives.
Sent from my SM-G973W using Tapatalk
Something is definitely wrong and I suspect that VR is causing that wear to the rotor guides/collector rings
mine was a different looking OEM regulator and brushes were worn even and the " rotor / end "
cleaned up to new with a little polish
mine was a different looking OEM regulator and brushes were worn even and the " rotor / end "
cleaned up to new with a little polish
Brush has impurities in it, that is what causes the scratches
a little 320 between the brush and slip ring to resurface the brushes
and put it back together, will run a long time still
no need to replace anything at this time
the slip rings are easily replaceable, if you can get the part -- same for the brushes
we live in a throw away environment these days
a little 320 between the brush and slip ring to resurface the brushes
and put it back together, will run a long time still
no need to replace anything at this time
the slip rings are easily replaceable, if you can get the part -- same for the brushes
we live in a throw away environment these days
Black with a green cover that would be a: T900XHD - Voltage Regulator Brush Holder Assembly, Extreme Duty, 12 Volt, A-Circuit, I-D-A Terminals, 14.8 Vset, w/o LRC, For Ford 6G Series Alternators
Which them begs the question, 14.2v at the battery or off the OBD2 port?
Do you have a picture of the label on the alternator????
And where did you get the alternator from????
A few stills of mine, from whenever I finish a video on testing and changing out VRs. This L-N had been in the truck for years.
![771595]( "771595")
![771598]( "771598")
![771599]( "771599")
Highlighting the brushes. Your brushes' composition is not the same; yours show a larger carbon particle or more porosity. Mine is denser.
![771604]( "771604")
Coloration, but you can't feel a wear line.
![771597]( "771597")
Which them begs the question, 14.2v at the battery or off the OBD2 port?
Do you have a picture of the label on the alternator????
And where did you get the alternator from????
A few stills of mine, from whenever I finish a video on testing and changing out VRs. This L-N had been in the truck for years.
Highlighting the brushes. Your brushes' composition is not the same; yours show a larger carbon particle or more porosity. Mine is denser.
Coloration, but you can't feel a wear line.
Attachments
The brushes that have the "copper color" like Jacks will last longer than the plain black brushes -- seen this many times
the reason one brush / ring wears faster than the other is from the electrical polarity of the connection
I suspect these companies use whatever is cheaper and readily available
A quick search on the inter webs gives this information
The Israeli automotive electronics company Taditel announced that it will establish a new production plant in China
the reason one brush / ring wears faster than the other is from the electrical polarity of the connection
I suspect these companies use whatever is cheaper and readily available
A quick search on the inter webs gives this information
The Israeli automotive electronics company Taditel announced that it will establish a new production plant in China
Yep, move to China.
I'm still wondering if that is a real L-N or one of the copies. I highlighted one of the retailers whom I really question if they are giving the customer what they think they are getting. From their video: "We take off the Prestolite label and remove the alternator from the Prestolite box to put it in a more secure cardboard box." And I own the Brooklyn Bridge. They countered in the comments, but ........
Quote from a carbon brush supplier -
Finding the proper carbon brush design for the operating conditions of your motor is the key to maximizing the life of the carbon brush and contact surface. Poor brush selection can result in fast brush wear and damage to the contact surface.
Each material is designed and developed to perform under certain operating conditions. A best grade for each application is offered, although, several grades with similar characteristics may offer satisfactory performance.
CARBON GRAPHITE
Carbon graphite grades were developed early in the history of motors and generators. These grades, therefore, are found most often on older equipment, particularly those with flush mica commutators. Carbon graphite offers cleaning action for use at slow speeds, low-current densities and medium to low voltages.
ELECTROGRAPHITE
Electrographite is the most common grade used on modern equipment. With excellent performance at high voltages, high-current densities and high speeds, wide ranges of characteristics exist within this category. Most electrographite grades are capable of handling overloads.
GRAPHITE
Graphite grades are used in special applications requiring low-friction characteristics. When brushes must operate at very low current densities or very high peripheral speeds, a graphite grade should be used.
COPPER GRAPHITE
Copper graphite has a material content of 15 – 95% copper or copper alloy. The added conductivity and lower voltage drop, allows metal graphite brushes to operate at very high current densities and low voltages.
SILVER GRAPHITE
Silver graphite has a material content of 8 – 95% silver. The added conductivity and lower voltage drop, allows metal graphite brushes to operate at very high current densities and low voltages.
I'm still wondering if that is a real L-N or one of the copies. I highlighted one of the retailers whom I really question if they are giving the customer what they think they are getting. From their video: "We take off the Prestolite label and remove the alternator from the Prestolite box to put it in a more secure cardboard box." And I own the Brooklyn Bridge. They countered in the comments, but ........
Quote from a carbon brush supplier -
Finding the proper carbon brush design for the operating conditions of your motor is the key to maximizing the life of the carbon brush and contact surface. Poor brush selection can result in fast brush wear and damage to the contact surface.
Each material is designed and developed to perform under certain operating conditions. A best grade for each application is offered, although, several grades with similar characteristics may offer satisfactory performance.
CARBON GRAPHITE
Carbon graphite grades were developed early in the history of motors and generators. These grades, therefore, are found most often on older equipment, particularly those with flush mica commutators. Carbon graphite offers cleaning action for use at slow speeds, low-current densities and medium to low voltages.
ELECTROGRAPHITE
Electrographite is the most common grade used on modern equipment. With excellent performance at high voltages, high-current densities and high speeds, wide ranges of characteristics exist within this category. Most electrographite grades are capable of handling overloads.
GRAPHITE
Graphite grades are used in special applications requiring low-friction characteristics. When brushes must operate at very low current densities or very high peripheral speeds, a graphite grade should be used.
COPPER GRAPHITE
Copper graphite has a material content of 15 – 95% copper or copper alloy. The added conductivity and lower voltage drop, allows metal graphite brushes to operate at very high current densities and low voltages.
SILVER GRAPHITE
Silver graphite has a material content of 8 – 95% silver. The added conductivity and lower voltage drop, allows metal graphite brushes to operate at very high current densities and low voltages.
@TooManyToys
"Black with a green cover that would be a: T900XHD - Voltage Regulator Brush Holder Assembly, Extreme Duty, 12 Volt, A-Circuit, I-D-A Terminals, 14.8 Vset, w/o LRC, For Ford 6G Series Alternators
Which them begs the question, 14.2v at the battery or off the OBD2 port?
Do you have a picture of the label on the alternator????
And where did you get the alternator from????
A few stills of mine, from whenever I finish a video on testing and changing out VRs. This L-N had been in the truck for years."
Wow Awesome insight/information. Below to answer your questions
14.2 on EDGE Insight CTS2
LN was on truck when I purchased - it has lasted many years just disappointed local reps can't get replacement parts required without extreme lead time (months). Worked really good with 16.5 warn winch to assist batteries when pulling truck/23' holiday trailer out of mud.
![Image]()
Sent from my SM-G973W using Tapatalk
"Black with a green cover that would be a: T900XHD - Voltage Regulator Brush Holder Assembly, Extreme Duty, 12 Volt, A-Circuit, I-D-A Terminals, 14.8 Vset, w/o LRC, For Ford 6G Series Alternators
Which them begs the question, 14.2v at the battery or off the OBD2 port?
Do you have a picture of the label on the alternator????
And where did you get the alternator from????
A few stills of mine, from whenever I finish a video on testing and changing out VRs. This L-N had been in the truck for years."
Wow Awesome insight/information. Below to answer your questions
14.2 on EDGE Insight CTS2
LN was on truck when I purchased - it has lasted many years just disappointed local reps can't get replacement parts required without extreme lead time (months). Worked really good with 16.5 warn winch to assist batteries when pulling truck/23' holiday trailer out of mud.
Sent from my SM-G973W using Tapatalk
It's a commercially designed alternator (done before Chinese ownership), so it should be awesome with a winch. It is set up with cooling and welded components to handle long periods of high output.
That is the correct labeling; it should have been made in 2012, the 8th week if I have their numbering correct. It changed later on.
The identification of the HD VR of yours does not match mine, probably ZMANNs, and I believe in others. That could have been a factory supply issue, or someone changed it before you. The L-N factory regulators for it (-2 and -3) are labeled R007520270 and in the literature.
The PCM version (-1) is a R007520269.
Since you didn't hunt it down, here is the data if you don't have it.
The service parts list.
The brochure
As hydro alluded to, the black/green VR was probably the cause for the wear on the ring. The rings can be replaced or lathed down.
Depending on the channel you are reading for voltage, OBD2 can report up to 0.5v lower than seen at the batteries, so it's always best to confirm at some time what you are actually outputting at the alternator. That discrepancy has been the cause of many alternator changes.
That is the correct labeling; it should have been made in 2012, the 8th week if I have their numbering correct. It changed later on.
The identification of the HD VR of yours does not match mine, probably ZMANNs, and I believe in others. That could have been a factory supply issue, or someone changed it before you. The L-N factory regulators for it (-2 and -3) are labeled R007520270 and in the literature.
The PCM version (-1) is a R007520269.
Since you didn't hunt it down, here is the data if you don't have it.
Prestolite - Leece Neville
Prestolite Electric / Leece-Neville is a global manufacturer of alternators and starter motors selling into niche markets for heavy duty (truck, bus, emergency, off-road), marine, military and industrial applications.
www.prestolite.com
The service parts list.
The brochure
As hydro alluded to, the black/green VR was probably the cause for the wear on the ring. The rings can be replaced or lathed down.
Depending on the channel you are reading for voltage, OBD2 can report up to 0.5v lower than seen at the batteries, so it's always best to confirm at some time what you are actually outputting at the alternator. That discrepancy has been the cause of many alternator changes.
Just a brisk walk on the trail, 
The reason to resurface the slip rings is to bring the surface back into concentric with the shaft center, the worn down spot is of no real consequence
I have had many armatures on the lathe that had severe "flat spots" or run out in the surface -- back in the day when we actually fixed stuff instead of replacing
The reason to resurface the slip rings is to bring the surface back into concentric with the shaft center, the worn down spot is of no real consequence
I have had many armatures on the lathe that had severe "flat spots" or run out in the surface -- back in the day when we actually fixed stuff instead of replacing
Sooooooooo, skimming this thread, is my 100 rpm surge at idle on a cold start is from my new LN230?
It only does it on the first start of the day
It only does it on the first start of the day
It's an annoyance issue. The GPCM is protecting from any harm. The time when mine is going to do it, I turn on the blower to high during the 90 seconds of initial running.
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