Hi guys, new to the forum and I’ve been doing a lot of reading these past couple days but I can’t find anyone with quite the same problems that I am having. I recently bought a 2005 6.0l with 215k. Driving around the past two days I have noticed that occasionally at idle (seems to only be when the truck is warm) my charging volts will drop down to the mid 11‘s and possibly quick taps on the lower side. The woman that I bought the truck from put a 180 amp DC power engineering alternator on the truck recently and said that the batteries were also recently replaced. Does anyone have any insight for me? I am leaning towards a bad alternator but it’s hard to believe that a lightly used 400+ dollar alternator is bad already considering that they only used it to tow their camper A few times a year. Thank you all in advance for any information you’re willing to give!
Charging system voltage drops
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Move the plug in connection back and forth while it’s running and see if the voltage jumps.
it can be a number of things, including out of spec brushes.
it can be a number of things, including out of spec brushes.
I don’t think that any of the stock wiring was replaced with thicker wiring due to the fact that lead coming from the alternator to the battery is still inside of the wiring harness Which I read online that if you go to a 180 amp or higher then you need to upgrade the wiring, do you think that it could be a possibility that the alternator is getting to hot due to that reason? The voltage goes back up when I raise the rpms even the slightest bit. I’m sure that it will be impossible for you guys to give me a definite answer but thank you for the info.
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Brushes come with a regulator.
With a 180a you have the potential for 180a, but once the glow plugs turn off you would have to turn on all the electrical devices on in the cabin to demand more the ~80amps (100 amps Excursion). There is little voltage drop under 160a in the stock wiring and you can run 180a for the short time to would ever happen.
The only time I would get hyper is if was a snow plow truck.
if you are seeing a lot of heat and low voltage it’s more likely a winding issue in the alternator and should be checked, but I have to say I never ran one of those alternators so I don’t have a good feel about how hot they run.
With a 180a you have the potential for 180a, but once the glow plugs turn off you would have to turn on all the electrical devices on in the cabin to demand more the ~80amps (100 amps Excursion). There is little voltage drop under 160a in the stock wiring and you can run 180a for the short time to would ever happen.
The only time I would get hyper is if was a snow plow truck.
if you are seeing a lot of heat and low voltage it’s more likely a winding issue in the alternator and should be checked, but I have to say I never ran one of those alternators so I don’t have a good feel about how hot they run.
It seems like they dont even make the alternator that is on my truck anymore. The part number on it is 001580 but the one that they offer on their website for the 6.0l is 001974 which I can’t find any voltage regulators, brushes, or anything for either of them.
I think that I’m going to have to just replace the alternator, do you think that a 135 amp alternator would do me any good? That seems to be the only one that I can find for my truck in the area and with the voltage dropping at idle like it is I don’t want to damage my ficm while I wait for a new one in the mail and have to replace that as well.
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135a should be fine. Down the line you could install a smaller diameter pulley to kick up the rpm which will supply a little more amps at cold idle. It doesn’t change the overall output, but at cold start idle it will act like a 160a.
You could get it checked at a specialty auto electrical garage, who may be able to see if there is something else going on. As you said, it’s a relatively new alternator and it would be a shame to waste it with an online diagnosis.
You could get it checked at a specialty auto electrical garage, who may be able to see if there is something else going on. As you said, it’s a relatively new alternator and it would be a shame to waste it with an online diagnosis.
Thanks for all the help man I really appreciate it, I think I found the problem, there is an adapter pigtail concerting the oem plug to the aftermarket alternator and one of the wires connecting to the old plug was pushed out of the new plug a little bit.
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glad it was not the alternator
DC Power stopped fixing the OEM line of alts under their " repair for parts agreement"
they said they can't get parts that work well anymore.. ,, I sent mine in months ago for a repair and it already degraded to a low 13.2 output, so I guess I was a recipient of bad parts ?
I bought a leece neville a long time ago and you can find all the parts for it and probably will for a long time to come
so thats what I run now
DC Power stopped fixing the OEM line of alts under their " repair for parts agreement"
they said they can't get parts that work well anymore.. ,, I sent mine in months ago for a repair and it already degraded to a low 13.2 output, so I guess I was a recipient of bad parts ?
I bought a leece neville a long time ago and you can find all the parts for it and probably will for a long time to come
so thats what I run now
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Glad to hear. It's best to check the simpler things first. There have a few alternators changed due to the connectors.
I was going down the leece neville road until I read about all the layoffs up north after the Chinese bought out there parent company. Lucky for me I found this great mom and pop alternator company Tucson alternator out of AZ. They offer up to a 370a 6 phase hairpin custom built to order for 350 plus shipping. You get a personalized spec sheet output for your alternator, and man that thing kicks butt, 14.8v cold 13.9v hot. Shuts my glowplugs off 5-10 seconds after startup and ficm main is 12.5 or 13 immediately after startup. I am very happy.
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Tucson has a website.
Wouldn't a 240 Amp be fine? What would be the true need for a 340 Amp alternator?
Wouldn't a 240 Amp be fine? What would be the true need for a 340 Amp alternator?
Well at the time I had the extra 40 bucks to get the larger one, but it was 350 then. I was trying to completely cover the glow plug draw at idle maybe 210 amps?idk. See ford keeps on the glow plugs up to 2 minutes after the engine starts, this is only to help reduce emissions, but on the 6.0, not the 7.3, the glow plug controller has over voltage safety and shuts them off at like 13-13.5v. So a really strong alt will overpower the gpc and shut them off and in turn your ficm will have 14 volts instead of 2 minutes at 11volts when its cold and needs the most. My theory idk, it seems to work really good.
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The FICM issue IMO is not after the start, it's during start when the starter current draw goes over 1,300 amps (2,000+ amps with a 6.4/Mean Green) and the pull-down of the voltage. Unfortunately at the time, I could not record minimum spiked voltage, so just used the visual data in slow motion from what I capture, with is more then what we see on OBD2 displays.
With all the data I acquired and shown in my alternator test videos, by the time you engage the starter the GP amps are around 85. Without the glow plugs, under cold temps the battery absorption is low and the combined demand with GP is under 50a, quickly diminishing as the battery resistance increases. Under warmer temps, the battery resistance is lower, and with the higher acceptance your needs might get to 60a, again, GPs not included.
A 140a with a reduced diameter pulley or 160a to 180a is a good choice if you are hyper about the first 2 minutes of running time at cold idle.
But 12.0v to a FICM should not be hurting it. Guys that let the batteries oxidize, lose their cca capacity and never see the true voltage drop at the start are the ones of the most concern.
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With all the data I acquired and shown in my alternator test videos, by the time you engage the starter the GP amps are around 85. Without the glow plugs, under cold temps the battery absorption is low and the combined demand with GP is under 50a, quickly diminishing as the battery resistance increases. Under warmer temps, the battery resistance is lower, and with the higher acceptance your needs might get to 60a, again, GPs not included.
A 140a with a reduced diameter pulley or 160a to 180a is a good choice if you are hyper about the first 2 minutes of running time at cold idle.
But 12.0v to a FICM should not be hurting it. Guys that let the batteries oxidize, lose their cca capacity and never see the true voltage drop at the start are the ones of the most concern.
During the 3 second starting period the voltage drop cannot be helped as long as Batts are in good shape. As your graphs show as you increase in alt output you shorten the period the gp are active thus shortening the period the system is running at reduced voltage. The quicker you overpower the gpcm the less time your alt is forced to output its max capacity. I don't see a downside to higher output if the extra cost is reasonable.
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It only does that with the L-N as it has a voltage regulator that will allow over the 14.5v threshold of the GPCM. I have no issue humping amps if that's what someone believes they want/need. I run the Leece-Neville 230a. But if you are down to 11.0 volts during GP operation, you have a battery issue. Even people with failed alternators haven't shown that, but usually around 11.8v.
The question is, is it needed if the FICM is not at risk, which based on the later Ford programming warning of 4 seconds @9.0v and 60 seconds @10.4v, 120 seconds @12.0v is not.
Am I am guessing you have not experienced the voltage oscillation from the alternator/glow plug tug of war since no concern over the GPCM or glow plug life? It's what usually shys people away for the L-N.
The question is, is it needed if the FICM is not at risk, which based on the later Ford programming warning of 4 seconds @9.0v and 60 seconds @10.4v, 120 seconds @12.0v is not.
Am I am guessing you have not experienced the voltage oscillation from the alternator/glow plug tug of war since no concern over the GPCM or glow plug life? It's what usually shys people away for the L-N.
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