Nations Alt & W-T Mod

[Andyba20]

Posted this in the article comments earlier, but figured I’d get more opinions by starting a new thread.

 

Doing the W-T mod this week, wanted to check in one final time and see if there were any new updates or changes to the mod I should know. I am putting in a new Nations 180 amp alternator too. Any suggestions on best place to mount the 200amp fuse holder for the b+ wire? Did Mike/W-T’s biblical like Paul vs Barnabus disagreement about the parallel cables ever get settled? I don’t want to run 4 giant cables across my radiator, but I really really don’t want a fire, or toasted alternator. 

Mike still says no need for parallel cables as long as grounds are all good/clean/solid. I might take a hybrid approach and at least add a ground cable…I do use a winch off the passenger side battery. 

[W-T]

The thermistor located on the drivers side battery is providing feedback to the PCM in order to regulate the charge rate. Correctly double-strapping the storage cells assures the parallel configuration to be absolute. Do not rely on motor grounds or body grounds to provide the minimal resistive path between the two batteries.

The thermistor provides thermal resistive current changes to a comparator within the PCM and these changes are tracked within a half of a degree C to maintain proper charge rates over a very wide temperature range. 

 

The original configuration had the alternator passing current to the drivers side battery first. With the W-T mod, the B+ charge is now provided to the passenger side battery.

 

The temperature sensor is alike the thermometer placed into the baby's butt for absolute reference hence, exact parallel configuration is required to eliminate any extraneous DC resistance that will be incurred if one relies on the cheap budget minded configuration provided by OEM specifications. 

 

The mediocrity of the original factory DC layout had no regard for excellence. The upgrade to a Nations 180 Amp alternator where the B+ is now provided at the passenger side battery positive post deserves attention. Double strapping is the correct and error free method to provide equal charge between the two cells and eliminate extraneous DC resistance at extremely small levels that nullifies the accuracy of your thermistor providing absolute results to the PCM's comparator circuit. This fries batteries and undercharges in other aspects.    

 

Your winch configuration will also benefit in regard to your connection points being applied to the passenger side battery. 

 

The addition of strapping between the two cells is done with #4 gage cable and lays into the top of the radiator and air/charge cooler troughs, done correctly it looks killer.

 

  

 I have AGM batteries, the cost was twice, what Fred Flintstone wet cell's costs because I do not allow sulfuric acid fumes to fart all over my electronics under the hood. After 20 years this truck is flawless electronically due to the elimination of mediocrity.  Budget, yeah...I understand that however; when you're chasing electronic errors that continually haunt you for years, sometimes it's just best to do it correctly the first time. 

 

I have NO comment on the additional 200 Amp fuse mentioned in the post...it was never in the Original W-T article for a reason.

 

Cheers,

 

 

[Andyba20]

First @W-T Thanks for the reply, and thanks again for pioneering this solution. I thought I’d read every single article and post on this mod over the past 6 months, but I don’t think I ever saw you specifically not endorse the b+ wire fuse. You left it out for a reason, can you share? 

[W-T]

Well, I'll try not to ruffle feathers but, I've been known to do so....

 

The original DC charge wire traveling across the top front of the entire engine bay terminated into the PDC box on the drivers side fender. I'll assume you know this and if so, then you also know about the fuse directly at the point of termination. It's a 140 Amp fuse that feeds the entire system within that box. 

 

Examining the box reveals a tremendous amount of "other" fuses that distribute DC to various points within the vehicle. Any other connection point drawing current is protected by the individual fuses.

 

The 140 Amp fuse is worthless in that location and all other circuits are protected by their own individual fuses or circuit breakers. Allow a moment for review regarding these protective devices known as fuses or circuit breakers...they sort of work...but, not really, but, kinda-sort of function....I'm being ambiguous in a distorted way on purpose.

 

They are there to break current flow in a catastrophic dead short to GROUND. They are there to prevent an electrical fire in regard to a vehicular accident. Any sensitive electronic device connected within the DC system of these vehicles will be subject to damage because the time it takes for a fuse to open (blow) or circuit breaker to react exceeds 20 milliseconds. 

 

Please note the single #1 gage wire connected directly to the starter motor and that wire is DIRECTLY connected to the positive terminal of the drivers side battery. NOW this is a heck of a wire! But, you'll notice it has NO fuse!  The reason is because, the solenoid on the starter motor will over heat and fail to close during continuous cranking condition of the ignition switch. Any Cummins 5.9 that won't start within a very short period of time has issues and intermittent operation of the starter motor in these vehicles is just that....intermittent operation. Good, because these starters can sink more than 800 Amps in a given condition.

 

Observing your new 180 Amp Nations alternator, the stud on the back connects directly to your passenger side battery + terminal. That alternator is commanded by the PCM and at idle (assuming your pair of batteries are healthy) the nominal charge arriving at the B+ post is minor in regard to having the Cummins spinning at 800 RPM's hence, the output of the alternator is minimal. Now, let's look at the BATTERY B+ post that's inline with this new 200 Amp protective device...in a complete act of buffoonery who would take a large wrench and touch the backside of the 200 Amp fuse to GROUND? Seriously, who would do such a thing? It's NOT the output of the alternator opening this fuse...it is the tremendous current capability of the battery itself passing current to ground and opening the fuse. 

 

Look at a 1965 Ford Falcon with an inline six cylinder engine...does it have a fuse between the alternator and the battery?  How about a 1967 Plymouth GTX with a 440, or perhaps a 1969 Chevelle SS 396.... the idea is or was never incorporated due to the understanding of current flow. Daimler Chrysler was in great error placing a 140 Amp fuse on the input to the Power Distribution Center in this manor. It will not protect the alternator because the alternator must be at very high level RPM's and have a command from the PCM to excite the field within the alternator to produce maximum current in order for an external fuse to blow due to excessive current demand. Keeping in mind the amount of time to open a fuse or breaker with a potential of 140 Amps at 14.8 Volts DC which mathematically equates to over 2 kilowatts...in a fraction of a second (less than 20 milliseconds) sinking that kind of power directly to ground is going to wipe the alternator into an oblivion. 

 

Anyone telling you to place a fuse on the output of your alternator to protect your alternator is in great error.  I find it comical and I've not said anything about this for years because it's just silly.

 

I believe money can be well spent in other areas and this aspect is not one of them. However, to each is his own 

 

With Respect,      

[Dieselfuture]

I love reading W-T posts always something to learn, but I was under assumption that the fuse is there just in case alternator shorts to ground internally somehow and blows the 140 amp fuse instead of all other fuses and whatever else.  or maybe that's the pcm mod I can't remember I did both just in case. 

[Andyba20]

Well I’ll be dadgum..I guess I’ll lose the fuse, and hit the welding store tomorrow for some parallel cables. I’m no buffoon, we’ll i am, but I won’t be In the case. 

[Andyba20]

Got it all finished and put back together. Massive improvement in shifting, and no TC lock/unlock at all…Only annoying issue was Nations somehow had put the wrong pulley on the alternator I got. In their defense they were cool about it, and answered the phone on the first ring each time I called. They sent me a replacement pulley (which wasn’t the nice anodized billet pulley in the picture they have on the website, but whatever). Both batteries are putting out exactly 13.84 at idle, and I haven’t done the parallel cables yet, though I think I probably will. 

[W-T]

It's nice that Nations would provide the correct pulley as this assures the idle charge rate to correctly track via command from the PCM. I see your 13.84 volts DC to be correct with regard to healthy batteries following a "start" event and indicates proper replenishment current flow. An improper pulley would most likely produce a noticeably lower charge rate. I commend your plans to follow through in double strapping your storage cells. The added complexity is worth the cost/effort to truly isolate the "power supply" integrity and assure both cells being charged according to temperature correlation. This will allow excellent performance of the planed winch accessory and replenishment charge following its use when required.

 

I would encourage the inspection of the alternator's mounting structure. The ground attachment is quite robust physically and each bolt is your DC ground return point hence; DC integrity dwells within this mounting assembly and requires attention in cleanliness to eliminate minute DC resistance. High current generation with poor mounting disciplines leads to electrolysis and increases DC resistance over a period of time through the cancerous action of current flow. Grease your threads and clean your holes is a good method to prevent errors for long term reliable performance.

 

Nice work, Cheers

W-T         

[Doubletrouble]

 Very informative