Chassis battery charging from generator while driving

[Bobby Wilson]

I have a 2005 Beaver Patriot Thunder with Cat C-13.  While driving yesterday almost to my destination I stopped for fuel and did not stop by diesel engine or generator.  When I started to leave the fuel stop the transmission would not go into drive and I noticed the dash error light "check transmission" and the Aladdin screen was blank.  I cut the engine off and tried to restart but the starter would not turn.  I had to cut the generator off to determine the starter was not operating.  I pressed the dash switch "battery boost" and the engine cranked as normal and the transmission went into drive, however before getting out of the parking lot the transmission quit.  I cut the engine off and again started with the "battery boost" and started out again.  Soon I noticed the transmission not shifting correctly so I held down the "battery boost" and everything worked well even the Aladdin screen is now working.  I travelled about 15 miles to my destination by pressing the "battery boost" as needed when the battery voltage dropped to 11 volts and it would go to 13 volts as long as I used this boost.  A few hours after I was plugged into shore power the chassis batteries now read 13.6 volts and the engine will start as usual without the "battery boost", so the inverter/charger charged the chassis batteries.  It can't understand why the generator would not do the same.  I suspect my alternator is defective but can't understand why the chassis batteries were not charging while the generator was running.  A friend told me the BIRD controller and the Big Boy stopped this if the ignition is on because the BIRD has an ignition terminal on it.  Does anyone know it the chassis batteries should be charged by the generator while driving.
Thank You.

[Steve Huber]

Bobby,
The BIRD system manual is in Coach Assist. Strongly suggest you familiarize yourself with it. From the manual; "When the Gen set is running the chassis and coach batteries are isolated. Thus the chassis batteries will be charged by the alternator and the house by the generator."
Looks like the alternator is the problem. BIRD seems to be working as shore power charged both battery sets.
Steve

[Bill Lampkin]

Just a note: Last summer at the start of our trip, the alternator went bad. Our coach is a 2005 PT, C13. Found a replacement in Eugene Or. They had a rebuilt unit in stock, correct Leece Neville alternator; about $150 cash and carry. I had another shop put it in. (Elite RV in Harrisburg, OR). Not too bad an ordeal. 

https://alternatorsandstarter.com/

[Bobby Wilson]

Steve,
Thank you,  I found a mechanic on wheels near us in FL that will come on site and check out the alternator next week.
I will read the BIRD manual.
Thanks,
Bobby

[Michael DeFalco]

staying on topic my question is will both batterys hold their charge if you shut down the inverter? 

[David T. Richelderfer]

Not necessarily.  Certainly, the inverter is a major draw but there's also the propane and CO2 sensors, the engine and transmission brains, other 12v devices you may have powered up, fridge, etc.

[Michael DeFalco]

thank you