This past weekend I completed my "big 3" upgrade. New 160 amp quickstart alternator, odyssey batteries and supplemental 2/0 wiring from alternator to each battery. I also installed a 2/0 ground cable from the back of the alternator to the drivers side battery.

See this pic here...


Tonight was the first time I had to test the system at dark. I noticed right away that at idle as I play with the throttle and rev the engine my interior and exterior lights surge (brighten and dim) with the fluctuating RPM. Its very noticeable. I'm pretty sure it should not be doing this. It didn't do this before I swapped everything. I did monitor voltage through my cts and the voltage seems very touchy. By touchy I mean that it will hold 14.4v at idle and I soon as I touch the throttle it'll dip to 13.7-13.9v and come back up to 14.4v. IIRC my old oem alternator would stay rock steady until I put a real load on it.

Tomorrow I plan to disconnect the supplemental wiring from the alternator running to each battery and try that. Then may be remove the extra ground. None of that should make a difference though.

Any thoughts on what it could be or what I should check? I've a big road trip planned for this next weekend and would like to take this truck if possible. Thanks

 

Your right, none of that should make any difference. Are most/all of your lights LED or OEM style bulbs?

I have an intermittent bad connection on the top of my alternator, but that is the connector or the pins. I rarely drive truck during hours of darkness, but the lights are steady when I do or have.

I am inclined to think the fluctuation in charging voltage has a big part in the changing brightness of the lights.

 

You mentioned installing Quick Start Alternator. Is it the type with an external rectifier assembly?

 

Mostly stock halogen oem bulbs with a few leds on the interior. I also think the fluctuation in voltage is a factor.

 

This particular alternator is a single internal rectifier.

 

Is the internal voltage regulator an F600 or an F600HD?

(Or something else?)

 

That I am not sure of. I know the model number that I have is # F18253MHD160. Its the first alternator they offer in their 160 amp series.

 

I would telephone or email the business who sold the alternator and ask for the WAI industry trade number of the Ford voltage regulator fitted to the alternator they sold you. It will be easier for them to look it up than for a consumer to have to sleuth it out. Allow them the chance to deliver the customer service you already paid for.

Did you charge the batteries before installing them in the vehicle? As you probably know, but as some folks may not realize, new batteries, even thin plate pure lead absorbed glass mat batteries with a 2 year rated shelf life, should be charged with an independent charger just prior to installation in a vehicle. Installing discharged batteries in a vehicle and expecting the alternator will charge them can cause some alternators to fail rather quickly. That isn't to say this is what happened in this case, but the idea here is to surround and isolate the problem, by cutting it off from all other possibilities of doubt.

After fully charging the batteries individually, the next least invasive step might be to load test the batteries individually, as voltage alone under no load does not indicate a battery's health. The problem you reported is a voltage dipping upon throttle blipping. That has the possible appearance of a current demand increase that the batteries are not delivering until the alternator catches up.

With so many new additions in one fell swoop of an installation... two new batteries, new alternator, new wiring, new load centers (nice new Blue Sea unit on top of the driver's side battery did not escape notice)... the process of elimination can be more tedious. Yet none of the effort is wasted, because what if you were sent a bum battery? What if the voltage regulator in the alternator was defective? The only way to find out is to test.

How many minutes has the engine been running before you made your voltage dipping observations? Was it within the first couple minutes after start up? Or much later, after it has been running for at least 5 minutes?

Is there any aftermarket communications radio or amplifier that is set to automatically power up with key on? Have you tried pulling the fuses for those loads and retesting?

 

I am always quite weary of creating additional power paths. And there is really no reason to do so, unless you have very unusual added electrical items on your truck. Did you remove the other alternator connection?

 

YZKW57...

I did charge the batteries a day before the install. They both charged up fine.

Did some more testing earlier and just blipping the throttle in the drive while at idle the lowest voltage I saw was 13.9v while the highest I saw was 15.8v. Once I stop blipping the throttle it settles back down at 14.4v and will stay there. I did disconnect both auxiliary positive cables and the extra ground that runs to from the back of the alternator to the drivers battery and nothing changed. I knew it wasn't going too. Just needed to eliminate it from my mind. I did call quickstart and told the guy my findings and he said thats a characteristic of a high output alternator (I am unsure of this) and that the reason it was not noticeable with the oem alternator was because it was so underpowered. Not sure if he's giving me lip service or not. He also said that as long as it wasn't overcharging there's nothing to worry about. This may be just annoyance I have to live with.

I am happy with the alternators performance. While at idle I can turn on an additional 50-60 amps worth of accessories on top of what the truck is pulling and it holds steady at 14.4v The oem alternator couldn't do that.

 

The explanation from quickstart is somewhat disingenuous and quite inaccurate, but it is possible that their regulator is simply crap (this is not because it's a high power alternator and the OE one is underpowered, it's because this regulator is worse than the OE one) and it has a hard time maintaining voltage stable when the alternator changes output because of the increased RPM from idle: in a 'high power alternator', a real one from Balmar say, the voltage would fluctuate quite a lot less. Then again, a Balmar 160A alternator with its regulator runs $1,400-$1,800. It is quite possible that you'll have to live with it: what you could do to make sure is basically isolate the alternator from the truck and connect it to a known constant load (say 4 or 5 headlight bulbs in parallel?) and a known good battery as well as a logging scope or something of that ilk. If, at that point, you get voltage fluctuations when blipping the throttle you'll be certain that the issue is with the regulator and you can act accordingly.
Looking at their website and 'rectifier ratings' of 400/600 amps on a 160A alternator and trying to upcharge 100% for them... yeah, the explanation meshes. I am willing to bet you'll find out that the issue is with the regulator, except it won't be because it's 'high power'.

I would personally, by the by, not recommend running running FLA or especially AGM batteries at 14.4V as a steady state: you are overcharging and will shorten their lifespan.

And BTW, 50-60A of accessories certainly counts as 'unusual'... what do you have on the truck, out of curiosity?

 

15.8V is not good for AGMs, or any VRLA (Valve Regulated Lead Acid) battery. The voltage regulation in that alternator is not acceptable, IMHO.

The $650 invested in the pair of Odyssey batteries under the hood cost two to three times that of the alternator, and as such, with the alternator being the lesser expense, that alternator would be the first to get kicked out of my truck.

Enersys provides this guidance on charging Odyssey batteries:

See the Support and Technical sections of the Enersys website for more useful tips on charging Odyssey TPPL AGM batteries.

I knew that your cables were not the issue either (unless they where shorting on engine roll, such as when the accelerator pedal was blipped), but that would have been too obvious. My concern was only any added loads. I checked your engine bay again, looking for a GPCM, as those modules can play tricks on voltage regulation during the first couple minutes after start, but you don't have a GPCM. Your cables are routed fine. As the person who first invented the idea of using a dual terminal MRBF block directly mounted to the alternator (no one had ever done it before), you're certainly not going to hear any objections voiced from me on your extra wiring.




Oh really? I have a 230 amp alternator, not just a 160 amp alternator... plus, I have a second alternator (dual alternator system) to boot, and I have never experienced what you have described in this thread. If having to choose a truer statement between A) "that's a characteristic of a high output alternator" and B) "giving lip service", I would be inclined to select B as being more probable.


Sorry for the blurry photo... the point here is to see that the alternator I installed is 230 amps, and it is available sold through Ford and International dealers (original/optional equipment on the LCF) so there is an OEM vetting process that helps assure stable voltage regulation by design. Glow plugs can get blown at 15.8v. Voltage should not exceed 14.4v.


If you are seeing 15.8V, it is overcharging, therefore, in his own words, that is something to worry about. Did he ever tell you which voltage regulator is in the alternator he sold you?


An annoyance, as well as an additional untimely expense (reduced battery life) if the voltage regulator is suspect. I wouldn't live with it, especially if the alternator is less than 30 days old and there is still an opportunity to return it.

 

I bought the same alternator on 9/26/2017 and installed it in the middle of October in 2017.

I bought this alternator because Brian42 had some good results with it and I needed a slightly higher output alternator than OEM. In addition, this was the lowest output "high output" alternator with all American made parts. There were two or so below this one that had parts from China, which the listing was very clear about.

Never once have I noticed the voltage above about 14.2 and is normally in the high 13's. This is based on my onboard voltage meter in the dash and if/when I was monitoring it via the OBD port. I suppose the voltage could have gone higher than the 14.2v that I am reporting here, but not that I have ever noticed.

Again, I have an intermittent bad connection at the alternator plug/harness from time to time, but I just live with it because it goes away after a few seconds.

F0rdC0wb0y, below is a link to the warranty and return policies of the company.

https://alternatorparts.com/warranty-return-policy.html

If it were me, I would pursue a refund or a replacement based on the 15.8v reading. Generally anything over 14.7v is considered to be over charging. The guy on the phone did not do the right thing and this does not represent the company well. Maybe things have changed in the build of the alternator or perhaps you got unlucky. Either way, that alternator is not suitable for service in your truck.

I am sorry you are experiencing this sort of trouble especially after following my install of the AGM batteries, alternator and Denso starter.

 

Three sets of 20amp kc lights.

 

No problem sous. I'm glad I can come to this place and get yalls opinions on this stuff. I think if I return it, I am not going to get a second one from them. I'll go another route.

Y2KW57.....what alternator are you running? Where can it be picked up?