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Topic: Dead start battery (Read 556 times) previous topic - next topic

Dead start battery

We own a 1995 U320 with a Cummins M11.  Yesterday Cummins installed a new starter and cleaned all grounds. We spent the night on shore power, however, this morning had  a dead start battery.  Reading the wiring diagrams it appears very little runs off the start battery.  What could have caused this??
Stella
1995 U320 40'

Re: Dead start battery

Reply #1 –
I would check battery connections especially the negative. also recheck connections at starter. Have you checked the voltage at the battery. It can be alot of things. 
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: Dead start battery

Reply #2 –
Be aware that the start battery is NOT charged by the converter or inverter/charger-- at least from the Foretravel factory.

Of course how fast the start batteries discharged depends on their condition, size as well as parasitic load.

I would suggest making some provisions for charging the start batteries from shore power-- either a smart relay such as Xantrex Echo charger or a separate small smart charger.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Dead start battery

Reply #3 –
Check the water level in the cranking battery and add distilled water if needed, then fully charge the cranking battery by leaving the boost solenoid closed all day, then disconnect the negative cables from the cranking battery and let it sit disconnected overnight. If the cranking battery is dead in the morning you need a new battery.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: Dead start battery

Reply #4 –
I installed a Yandina combiner across my boost solenoid terminals. In my 95 U300 the dash radio and cigarette lighter socket run off the start batteries. I run sirius radio and leave the head unit on while camping. Anyone with this style setup who doesn't have a battery combiner is crazy.

Combiner 100 Sheet

best, easiest to install add-on ever. took me twenty minutes from start to finish. anytime the inverter is charging, it is charging both banks. I can run parking lights on the side of the road and never have a dead battery. and I'm not limited to some lame 15 amp xantrex POS. Just hearing that brand makes my blood boil after the luck ive had with their products.

I have no clue why your start batteries died, but I know on mine there are many loads that run off the start batteries that probably shouldnt. I'm sure yours is similar.
Matt
95 U300, 78k miles
Cat 3176 Jake Brake, HD4060.

Re: Dead start battery

Reply #5 –
I strongly suggest you test your battery, as I described above, before you start messing with your coach. It seems much more likely to me that you've got a bad battery than a wiring problem, just saying.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: Dead start battery

Reply #6 –
Stella,

You are leaving a lot of information out. Need to know when the last time the engine started, why did Cummins install a new starter, any earlier symptoms, etc, etc.

You need a digital meter so you can always monitor both battery banks. That way, you won't have any surprises. Can be two digital lighter socket meters, one in the dash socket and the other by the driver's left knee.

Read current post about keeping engine batteries charged.

Photo shows the two digital meters hard wired with the plug in meter at the bottom of the photo next to the key. The 12.33 reading is for engine batteries and is after about a week of sitting without charging the engine batteries. 12.33 volts is about half charged and low enough for the engine batteries to start to sulfate. 12.7 volts is considered a full charge. The 13.12 is a maintenance/float voltage the OEM charger is putting out. The house battery manufacturer would like a couple of tenths more but they work like new after 6 years.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Dead start battery

Reply #7 –
Stella, did you check the start battery voltage with a meter?  You say you have a dead start battery, would a better description be the starter did not crank, which could be a missing cable connection, and maybe the start battery is ok?
 

Re: Dead start battery

Reply #8 –
Quote from: car54 –
I installed a Yandina combiner across my boost solenoid terminals. In my 95 U300 the dash radio and cigarette lighter socket run off the start batteries. I run sirius radio and leave the head unit on while camping. Anyone with this style setup who doesn't have a battery combiner is crazy.

Combiner 100 Sheet

I installed the 160amp one: Combiner 160 Sheet

and I removed the combiner.
1998 U270 34'