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I recently purchase a 1991 mallard sprinter 24 foot class C for my trip around the states. I plan on adding 4 6 volt 230AH batteries. The chassis is a Ford E-350 with a 460ci motor. 1) will the alternator charge all four batteries? 2) will the generator Honda 4k charge all four? 3) should I buy a 3 stage charger to run off the generator for charging? 4) has anyone mounted a battery box on the front receiver hitch? Thanks in advance, Kurt

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1. The alternator will do a fair job of charging the batteries, not up to 100% and not as fast as as you might like. If the batteries are very low and you have a small alternator you might overheat and possibly kill your alternator. If you have a big alternator you might end up charging the batteries too fast and shorten their lives.


2. I don't think the Honda will do much of a charging job without the addition of an external charger or a good smart converter.


3. Yes, to charge your batteries off the generator or shore power a good (smart three stage) converter is a very good option.


4. I haven't mounted a battery box to a receiver hitch, they are a bit heavy and the hitch design a bit bouncy for my taste. If you have the spare weight capacity on the front axle once you are loaded for travel you could probably do it though. I'd lean to getting a welding shop to make me up a platform coming off the frame rails that would be sturdier.

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Kurt, I pretty much agree with the good Stanley man, so here is another stab at you excellent questions.



1) will the alternator charge all four batteries?


YES sort of, assuming wired correctly it can (subject to alternator and its voltage regulation) add a good degree of charge (NOT perfect or as complete as a 3/4 stage Smart Charger) to your house batteries. I have a stock alternator in my 2001 Chevy and four 6 volt 230 Amp Hour golf cart house batteries in series/parallel. I have a mechanical isolation relay with a time delay such that after my engine starts and the engine battery has time to recover and stabilize the relay closes and No 4 copper cables then essentially place the 4 house batteries in parallel with my engine battery and alternator. I have a digital voltmeter on my house batteries and while driving coupled to the alternator as noted their voltage will start out around 14.2+ volts, but after a while stabilize at around 13.9 to 14.1. Of course, this depends on my alternators voltage regulation circuit and the resistance in my cables and relay etc. Your alternator with its voltage regulation circuit and you batteries and cables may perform different NO ONE CAN ACCURATELY SAY


NOTE big cables, hopefully short runs, with low resistance connections and relays etc to the house batteries is essential. IE don't run 20 feet of 10 Gauge wire back to the house battery bank and expect great results as voltage drop will occur across the wire. I have 2 or 4 gauge (I forget exactly) cables of around 7 feet back to my house four battery bank.


NOTE even if I drive 8 hours and my house batteries measure somewhere around 14 volts all that time (indicates they are indeed receiving some current flow charging), if I get to an RV park and plug up my Smart Charger IT STARTS OUT AT 14.4 VOLT OR MORE BULK CHARGE RATE ACTING LIKE THE BANK IS NOT FULL CHARGED before it backs off to 13.6 Absorption then 13.2 Float voltages. But that may just be how it works?????


NOTE one thing I don't have but recommend is an ammeter in the circuit back to the house battery bank to see exactly how many charging amps flow to the batteries. I have a digital volt meter there but an ammeter would provide more information.


NOTE the house batteries in parallel with the engine battery is a current divider and how many alternator charging amps flows to each is a function of the battery state and resistance in the cables and relays and where voltage is sensed etc etc and hard to calculate setting here absent a ton of data. All I can say is what I posted above, if cables and resistance and relays and voltage regulation scheme and where and how the batteries are connected is different YOU GET DIFFERENT RESULTS




2) will the generator Honda 4k charge all four?



Sorry, I don't have info as to how many 12/14 DC volts and amps that generator can produce for battery charging purposes, but wouldn't expect t to be great enough to charge four 6 volt golf cart batteries very fast at all. IT DONT SOUND LIKE A GOOD PLAN TO ME but again no data so I cant say yes or no



3) should I buy a 3 stage charger to run off the generator for charging?


I LIKE STANLEY WOULD DO THAT. That way you can utilize the full 4K watts of generator energy versus what I'm GUESSING is a much lower energy rate as above PLUS a Smart 3/4 Stage Charger will do so much better job to fully and completely charge your batteries then the Honda (again guessing no warranty I don't have the Honda specs)



4) has anyone mounted a battery box on the front receiver hitch?


Not me but I bet its been done by someone. BE SURE THE BOX IS ADEQUATELY VENTED WITH SUFFICIENT CFM for cooling and exhausting potential hazardous gasses.



SUMMARY it can be done (SUBJECT TO your alternators capacity, don't overcurrent overheat and trash it) and I suggest good quality short cable runs with big enough copper wire and a quality isolation relay with time delay and a volt and amp meter to show exactly how many charging amps and volts the battery bank is receiving. WARNING just because mine works dont mean yours will. If you start pulling max amps out of your alternator for long periods IT MAY OVERHEAT but the current divider between your engine and house battery bank, I just cant say hot much current flows which way and I don't see how anyone can absent all the specs and data. Mine works but will yours??????????????????????????????????????


Best I have to offer based on the info available


John T

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