load drop damaging alternator

[booster]

Originally Posted by InterBlog

Context matters quite a bit here.

Under normal automotive use, clutch pulleys may indeed reduce wear and extend the life of certain parts. They may perform as designed (I actually don’t know because I haven’t researched it).

But we are not talking about normal automotive use. We are talking about retrofitting a supplemental power system into which automotive alternators were never designed to be integrated.

Upfitters responded to the potential mismatch preemptively with a number of responses: Number one, larger alternators, which theoretically could handle the extra demands more effectively. Number two, intervening mechanicals, such as the Sterling battery-to-battery charger.

None of those measures protected a number of us who had our new alternators fail and who have chosen to discuss these things.

It’s worth nothing that ARV gave up entirely on the idea of somehow making stock alternators work for this purpose. I know that ARV is a dirty word (acronym) to some vanners, but if you haven’t seen this video, it might be worth 6 minutes of your time.

My understanding is that you have just the single, stock type, alternator in your Sprinter?


If so, the context of the situation has to include that important point. Nearly all the high charging rate systems are using two alternators now, and IMO that is a very important point. Some vans, like our 07 Chevy allow the second alternator to be parallel with the first if you want which leaves open some interesting ways to set it up. Most others can't run parallel so the second alternator is a standalone to charge the coach.


IMO, running a stock alternator to do high % of rated output charging nearly all the time is a recipe for getting a failure, regardless of brand of van and alternator. We had a 250 amp single for a while to try and see how it worked, and it just was working too hard, too much of the time for me to believe it would last a long time.


A nations 280amp second alternator in a Sprinter will give a net average of about 165 amps per very good data supplied by Avanti some time ago. It cycles of the high temp output reduction generated by the Balmar regulator so that is the average over the many cycles. That is just under 60% of rated capacity so that is about the amount of power you could take out continuously or cycling like it can do also.


Most stock alternators can't handle the high amp charging a lot as well as a dedicated high output alternator like the Nations, I think so know the alternator running temp is really quite important. Many stock alternators I have seen can't run over about 40% of capacity for very long before the get too hot.


If you don't currently have a two alternator system, you may want to consider it rather than trying to get the stock one to do things it probably was never designed to do.

[avanti]

Originally Posted by booster

Nearly all the high charging rate systems are using two alternators now, and IMO that is a very important point. Some vans, like our 07 Chevy allow the second alternator to be parallel with the first if you want which leaves open some interesting ways to set it up. Most others can't run parallel so the second alternator is a standalone to charge the coach.

One of the things I am excited about in our forthcoming Transit is its amazing OEM charging system. With dual alternators and dual batteries built in from the factory, and a max current spec greatly in excess of anything I will ever want, I am highly confident that the issue under discussion will be pretty much off the table.

One thing that nobody seems to know is how this system behaves when one of the alternators fails. It apparently has a "primary" and "secondary" alternator. The question is, what happens if the "primary" unit fails? One would hope that the "secondary" would take over and keep you from being stranded, but I can't find any source to confirm this.

[booster]

Originally Posted by avanti

One of the things I am excited about in our forthcoming Transit is its amazing OEM charging system. With dual alternators and dual batteries built in from the factory, and a max current spec greatly in excess of anything I will ever want, I am highly confident that the issue under discussion will be pretty much off the table.

One thing that nobody seems to know is how this system behaves when one of the alternators fails. It apparently has a "primary" and "secondary" alternator. The question is, what happens if the "primary" unit fails? One would hope that the "secondary" would take over and keep you from being stranded, but I can't find any source to confirm this.

I kind of thought you would be filling in some blanks on the Transit system as I would certainly think it is the way the future should be headed.


I, too, will be very interested in seeing and hearing just how it actually works in the real world. Do you intend to put some temp sensors on the alternators to see how hot they actually run when charging hard? I have read that, at least in pickups, when the Ecoboost engine is running hard pulling heavy loads and hills the underhood temps can get quite high, and that normally would also raise alternator temps.

[avanti]

Originally Posted by booster

Do you intend to put some temp sensors on the alternators to see how hot they actually run when charging hard?

Eventually, yes. I didn't have the upfitter install them, though. I already have so many sensors that it was getting embarrassing. Won't be hard, though. With the miracle of ESPhome, I won't even have to run wires from the engine compartment!

[InterBlog]

In both vids (ARV’s and Avanti’s), real-world conditions were not able to be shown. What happens with resonance and vibration when 400 miles of bad roads are added to the equation? Slamming over potholes and the like?

Relatedly, our alternator didn’t show any funny behavior before failing. It seemed to run about the same way with or without lithium charging being engaged.

Not yet mentioned on this thread (IIRC):

If you can install a SECOND alternator in your van model, this whole discussion is pretty much moot. Burn the danged thing out via clutch pulley failure or other pathway, and the worst that happens is that you will need to stop for shore power to recharge if you don’t also have solar or a generator. That is not a trip-killing or a life-ending scenario in most cases.

We have a 2006 Sprinter, and from a technical perspective, installing a second alternator was just too difficult. It’s been years now and I cannot recall the details as to why, but the vehicle just wasn’t built to optimize that possibility.

[booster]

Originally Posted by InterBlog

In both vids (ARV’s and Avanti’s), real-world conditions were not able to be shown. What happens with resonance and vibration when 400 miles of bad roads are added to the equation? Slamming over potholes and the like?

Relatedly, our alternator didn’t show any funny behavior before failing. It seemed to run about the same way with or without lithium charging being engaged.

Not yet mentioned on this thread (IIRC):

If you can install a SECOND alternator in your van model, this whole discussion is pretty much moot. Burn the danged thing out via clutch pulley failure or other pathway, and the worst that happens is that you will need to stop for shore power to recharge if you don’t also have solar or a generator. That is not a trip-killing or a life-ending scenario in most cases.

We have a 2006 Sprinter, and from a technical perspective, installing a second alternator was just too difficult. It’s been years now and I cannot recall the details as to why, but the vehicle just wasn’t built to optimize that possibility.

All our vans see those kinds of conditions, so I don't even know how that means much in what we are talking about.


Lots of people have the second alternator in the early Sprinters, AFAIK, so maybe they can join in and let us know what issues there are to installing the second alternator in them.


I just looked at Nations to see if they had a kit for the 2006 and you are correct that they don't. Can't say if they ever did though.


They do have a 280 amp alternator that is alleged to be a true designed high output unit. Depending on your power use and B to B size it might be a possible solution to the Bosch issues. It is claimed to be PCM compatible. If it like the rest of their 250 amp units it would Denso style hairpin wound with plenty of high capacity diodes and long life bearings. If that is what it is, it should be good at over 150 amps continuous without overheating, unless the engine compartment gets too hot.

[GeorgeRa]

Originally Posted by avanti

One of the things I am excited about in our forthcoming Transit is its amazing OEM charging system. With dual alternators and dual batteries built in from the factory, and a max current spec greatly in excess of anything I will ever want, I am highly confident that the issue under discussion will be pretty much off the table.

One thing that nobody seems to know is how this system behaves when one of the alternators fails. It apparently has a "primary" and "secondary" alternator. The question is, what happens if the "primary" unit fails? One would hope that the "secondary" would take over and keep you from being stranded, but I can't find any source to confirm this.

My 1999 F-350 had 2 alternators mounted on the top of the engine, I assume Transit is similar. Additional benefit in comparison to ARV/Sprinter with second alternator mounted in road clearance reducing, very vulnerable to road damage place.

[InterBlog]

Originally Posted by booster

….


Lots of people have the second alternator in the early Sprinters, AFAIK, so maybe they can join in and let us know what issues there are to installing the second alternator in them.


….

Just now, I asked my husband for a recap, and this is going back probably to the 2015 timeframe when he looked into it. The space available in the T1N Sprinter’s engine compartment was actually designed to accept a second air conditioner compressor, not a second alternator. In order to install another alternator, a special bracket was needed. My husband identified a company that would be willing to fabricate the bracket, but not before he agreed to sign a big fat waiver of liability, because in that particular Sprinter model, installing a second alternator was known to cause harmonics problems with the engine. Bolts vibrating loose was reported to be a big issue for early adopters. So my husband concluded that it seemed too risky, and we didn’t proceed down that pathway.

If there are owners out there who have successfully done it without long-term problems, I’d love to hear from them. One day in my copious free time, I may re-research the issue on Sprinter Forum.