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Thanks Sean. In BjornF16's posting of the literature, Ford changed the wording so it not clear if the top alternator is active initially, or as Pete noticed, it may not be.
My only concern here is we had the promotion that a high capacity alternator is needed to be installed to provide higher voltage protection during GP activity, yet Ford may have prevented that by design. If so, then high output alternators are not helping. So then we have to ask are the Ficms in danger with that strategy or did Ford know they are not so it was more important to protect from overheating and damaging the GP's, something I'm sensitive to after investing $16,000 for a broken GP.
My only concern here is we had the (premonition) that a high capacity alternator is needed to be installed to provide higher voltage protection during GP activity, yet Ford may have prevented that by design. If so, then high output alternators are not helping. So then we have to ask are the Ficms in danger with that strategy or did Ford know they are not so it was more important to protect from overheating and damaging the GP's, something I'm sensitive to after investing $16,000 for a broken GP.
Well I have an old harness that I can cut the plug off of and I also
have a new pig tail so it should be able to come up with connector
I can use to test for power with.
The thing that brought this up is my stereo head unit started not turning
on at start like it should and I started watching the SGII voltage and found
that it was really delayed after starting. When I first put that 140A in I got
very quick recovery time and now does not.
I finally got the PC working again. Seems I broke a file when I moved them to the new drive.
Still can't get the CD and DVD drives to read along with some broken programs
Anyway have a look at the very first part of 141-00-1
This is what is in the first paragraph. Functionality
In the single generator system, with the key in the ON position, voltage is applied through the
charging system warning indicator I circuit to the voltage regulator. This turns the regulator on,
allowing current to flow from the battery sense A circuit to the generator field coil. When the
engine is started, the generator begins to generate alternating current (AC) which is internally
converted to direct current (DC). This current is then supplied to the electrical system through
the output terminal (B+) of the generator.
Once the generator begins generating current, a voltage signal is taken from the generator stator
and fed back to the regulator through the stator circuit 4 (WH/BK). This voltage feedback signal
(typically one-half of the battery voltage) is used to turn off the charging system warning indicator
on the single generator system. Gas engines have an external stator circuit and diesel engines
have an internal stator circuit.
With the system functioning normally, the generator output current is determined by the
voltage of the A circuit. This A circuit voltage (battery sense circuit) is compared to a set voltage
internal to the regulator, and the regulator controls the generator field current to maintain
correct generator output.
This would seem to support the production of power at engine start.
I still need the read the full document. If someone gets that done please post your findings.
I am going to try and get the same info for each of the years.
03~04
05
06~07
P.S I think I have a elf running around loose. I found some 3D
printed stuff I don't recall printing but needed to. So the question is
do I have an elf of am I going nuts? Then again maybe one of the cats did it.
When we review the glow plug operation in the service manual it states "Then, depending on the readings from the engine oil temperature (EOT) sensor and the barometric pressure (BARO) sensor, the Powertrain control module determines how long the glow plugs will be on". And pretty much that is how the on-line story goes with usual queries of why does BARO matter. However ......
Go a little further and it reads "The glow plug ON time varies from 0-120 seconds depending on battery voltage, engine oil temperature and barometric pressure".
The reason I got interested in it was as I installed the small pulley on the L-N 230a and it got warmer out, I could watch my voltage fluctuate. As I was doing the segments for the alternator video that none of you have seen with the ammeter it would show the GPs switching on and off. At first I thought it was a bad GP module and got a replacement. Nope. It's the PCM shutting off the GP module once the alternator voltage peaks around 14.4. The regulator cuts back to a lower voltage then the GP module is re energized by the PCM since voltage is safe, for a second or two. So my choice is to rev up or turn on accessories to keep everything calm. Or reinstall the OE pulley. I've got it documented in the vid, another bit of info leaked.
Randy has mentioned his truck (2 batts) peaked to full voltage and stayed there, so all of this may be vehicle dependent. I've closely watched his third batt info to see if the added reservoir of a third batt influences this. Of course, he ain't got no problem.
Anyway, the point is the 6.0 PCM does limit the GPs for voltage. It just doesn't limited the stupidity of the nut behind the wheel from re energizing the GP circuit several times in extreme cold to afford the opportunity of paying $16,000 for a glow plug.
Jack, I had the ones you had not posted and thought that I may as well post them
as downloadable PDFs. Anyway we have them all in one place.
Some interesting things are coming up reading this.
I just thought of something else to look at.
A graph of battery voltage and glow plug current. I can see
over-voltage taking out a glow plug. After all they are similar
to a light bulb in that if you push too much voltage at them they go POOF.
That adds some new questions to the equation . Is it the
PCM that is controlling the cycling or the GPM. I know that the
PCM sets the over all ON time. However the GPM seems to be
to give plug resistance feedback to the PCM in the form of a
high,low or open.
We need a lab. But I don't see anyone offering one and there is no
real payback or maybe there is some but not enough that we could
get funded for doing that.
I think an amp probe on the GPM B+ input line would give us the
info on current usage Vs battery voltage.
Mind that this is all based on a single alternator system. In the dual
system the PCM does control the lower alternator on time during the
glow plug operation.
One thing that jumped out at me was the fact that Ford tells a mechanic
how to replace the regulator in the alternator when most just toss in a complete
replacement alternator and not bother with doing a regulator.
Yes, I do. In fact two now. Standard equipment on the 6.0.
Sean, the service manual page I posted states Glow Plugs - PCM-Controlled, top right and in the lower left. I'll take them at their word as its not a carryover system.
the service manual page I posted states Glow Plugs - PCM-Controlled, top right and in the lower left. I'll take them at their word as its not a carryover system.
Just to clear any confusion, I was referring to the 414 page on alternators, not the 303 page on the GPCM.
I wasn't confused. I don't think, well now maybe I am. But your quote of me was to Sean that I believe that the GCPM is controlled by the PCM for acceptable voltage.
And now after reading this latest round discussing glow plugs..... I have a glow plug issue worth mentioning.
I've been down one plug all summer, no issue... but now that's it's cold I've become active in its repair. Replaced the module on Friday as I got it at a good deal. Plugs 2, 4 and 7 have now coded, 2 was the offending plug all summer, 4 coded a month ago and 7 coded Friday...
If the module is being controlled, then this shouldn't be an issue. It should regulate the voltage as necessary and prevent an over-voltage burn out. Now if the module were to fail, then possibly an over voltage could exist, but then I'd suspect the controlled on-off times would also be effected and that they could eventually also be energized randomly from a failed controller and possibly see a code for the module, just not individual plugs.
Ford would have to assume that the plugs could be exposed to max voltage for the maximum allowed on time without catastrophic failure... or until the relay tripped or fuse blew (I don't know if it's fused). Anything less would be utterly stupid in the design!
People have assumed that the idea was not to burn out the alternators, but in my 2000 and 2001 service manuals, Ford states the idea of not turning on the second alternator was to protect the glow plugs.
They are a PIA to change, not matter which motor.
Furthermore, let's look at the OBS. The ambulance package on the OBS was a single 215 amp alternator. There were no dual alternators on the OBS. Why did Ford spend the money redesigning the front cover, redesigning the water pump, redesigning the AC bracket, redesigning and producing two new alternator brackets, redesigning the hoses on the water pump... for the virtually the same engine between the OBS and the Super Duty?
There are probably lots of reasons unrelated to this discussion, but what if ONE of the reasons was so that Ford could purposely limit electrical power production during glow plug operation by curbing the maximum output of the alternators (hence the downgrade to the wimpy 110a) and then providing two such alternators for the ambulance package or customers who anticipate higher electrical demands?
Before I purchased my high amp alternator, I posted a question on the 7.3L forum asking if anyone who upgraded their alternators ever noticed that they needed to change their glowplugs within a year or two thereafter. Not one respondent made the connection. Even when I explained why I was asking, no one reported any experience or "Ah HA" moment that linked a high amp alternator upgrade with an earlier than expected demise of their glow plugs.
But my query was hardly scientific. Respondents in southern and western climates might never see their glow plugs fail, even if they plugged their truck in to a Tesla Super Charging station. And respondents in North Dakota might accept glow plug replacement every 3 or 4 years as a fact of life. The answers I did receive only bolstered the bold departure from the OEM 110amp to the L-N 230amp... but given six years of service in the field, one would think that if a higher amp alternator were a problem, it would have been well documented by now. But it hasn't been. Or at least I haven't found one.
In fact, Jack, you are the only other person I have read who has raised this concern... the same concern I inquired about a month or so ago, and that I've been thinking about all year.
My first thought when reading the service manual regarding glow plugs was: I'm glad I didn't get the 14.9v DC Power alternator.
