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Topic: New starting Batteries, dead after sitting for a week? (Read 799 times) previous topic - next topic

New starting Batteries, dead after sitting for a week?

Just came back from putting in almost $30K at FOT. All new Batteries and a bunch more, It ran great driving back 1300 miles, The rig has been plugged in to 50 amp shore power since parked for 9 days and we thought everything was fine. We were to be headed out early in the am, I went to start the rig to pull in the slide and I'm 100% dead, no lights on the dash etc. So frustrated I can't even speak!

Any help appreciated.

Paul
Prior 2003 U295  40ft  400Hp -Sold
2020 F350 Tremor - Sold
2021 Bundutec Roadrunner - Sold
2017 Airstream Classic - Sold that POS
2017 F250 - Sold
2019 Sprinter Van - Sold
2022 Winnebago Revel 4x4


Army Airborne Vet.

Re: New starting Batteries, dead after sitting for a week?

Reply #1
I plug my coach into 50 amp shore power at home. It charges the house batteries. For the engine/chassis batteries I have a trickle charger plugged in. I don't believe the shore power will charge the chassis batteries unless the boost switch is activated. NOT a good idea to leave the boost switch activated for extended periods of time, thus the trickle charger.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: New starting Batteries, dead after sitting for a week?

Reply #2
Thanks for the reply. I've had other engine driven RV's. (this one is new to us). Never needed to trickle charge starting batteries before. Is this a Foretravel thing I need to be aware of?

I've got to assume that after buying all 3 new Redtop starting batteries that there is a demon somewhere drawing power. I do have a very good NOCO charger that I can hook up while on shore power, but that just seems crazy to me?

If anyone has any ideas as to what can be causing the drain, I'd appreciate your reply.

Paul
Prior 2003 U295  40ft  400Hp -Sold
2020 F350 Tremor - Sold
2021 Bundutec Roadrunner - Sold
2017 Airstream Classic - Sold that POS
2017 F250 - Sold
2019 Sprinter Van - Sold
2022 Winnebago Revel 4x4


Army Airborne Vet.

Re: New starting Batteries, dead after sitting for a week?

Reply #3
I killed a similar set quickly by leaving the headlights on,....

Only way I know to help the battery issues is to cross connect both battery bsnks.

I put in a auto/manual magnetic relay that disconnects the banks on  discharges.

Then I use a small solar setup to charge the bsnks,  With my particular old cheap stuff controller and undersized wiring through  the refer results in 13.54 volt batteries every time I check.

Same  red tops and three  mk 8g8d's.  no Charger,  direct to auto connect from,solar. 

You have your coach plugged in.  You might just need the auto connect ACR.

Better on a modern inverter which is temp compensated and can be set to cycle  the  batteries as needed or wanted.

A mechanical connection that auto disconnects on discharge seems the safety and easiest. 

"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: New starting Batteries, dead after sitting for a week?

Reply #4
Yes, from the factory (as with many other coach brands) the chassis batteries do NOT charge from 120 VAC.

Good choices are "smart battery combiners" and "smart stand alone small amp chargers".
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: New starting Batteries, dead after sitting for a week?

Reply #5
It sounds like something was drawing power from the starting batteries.
It is normal that without using Boost Switch that there is no charge to starting batteries when plugged in, but 9 days seems very short.
If you can't start, use the Boost Switch to join the house and starting batteries.
That will also put a charge into the starting batteries if plugged in.
I also use the trik-l start device to keep starting batteries charged. Ultra TRIK-L-START Starting Battery Charger/Maintainer
There are other similar devices.
Eric & Nancy
1999 36 Ft. U320 WTFE
2016 GMC Terrain

Re: New starting Batteries, dead after sitting for a week?

Reply #6
If the batteries are new and should be fully charged after a 1300 mile trip. Then the batteries are dead only after 9 days there is a problem that need to be addressed first rather than just throwing parts at it. Not saying that some type of charger isn't a good idea (we use the Trick-L-Start our selves) but lets find out what is causing the problem first.

You have ghost loads like engine and trans ECM units that you can't shut down (which no way should draw your batteries down in 9 days themselves) , headlight relays, map reading light, several things are on the buss that stays hot with the key in the off position. You need to start looking around to see what has either been left on or has developed a draw.

One of the batteries could have developed an internal short drawing the hole system down. I would start there in disconnecting them and seeing if a battery is bad then go from there . If a battery is bad no amount of charging (with what ever gismo you choose) will fix that. Some other things to look at is, the battery  isolator for failure, possible bad diode in alternator and things like this for your draw.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: New starting Batteries, dead after sitting for a week?

Reply #7
If anyone has any ideas as to what can be causing the drain, I'd appreciate your reply.
The best place to get "ideas as to what can be causing the drain" is the 12V wiring diagram for your coach.  Assuming you received a full set of factory manuals with your coach, the wiring diagram should be tucked away in one of the binders.  You can trace out the flow of power from your start batteries, and see exactly what is (or can be) powered by that battery bank.  Of course, any "custom wiring modifications or additions" done by prior owners will probably not be noted on the diagrams.  Might take some clever sleuthing to figure out what is draining the start battery bank.

Anytime you have a new "problem" immediately after having work done on the coach, the first place to look is where the recent work was done.  You got "new batteries and a bunch more...".  Was any of the "bunch more" new electrical equipment or devices?  Besides the things mentioned by Mike (above), another possible power drain is the entertainment system.  Anything new added there?

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: New starting Batteries, dead after sitting for a week?

Reply #8
My new radio with memory draws the bat down in about  16days .  I pull the radio  fuse  for parking and disconnect the bat for more then 2 wks.

Re: New starting Batteries, dead after sitting for a week?

Reply #9
Easiest solution is to get a trickle charger designed for AGM batteries,all the Foretravels have a drain,leave the charger plugged
in when not driving and forget about it.PS,fill in your signature with coach info so we can help better.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: New starting Batteries, dead after sitting for a week?

Reply #10
Paul, what is the year and model number of your coach?
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: New starting Batteries, dead after sitting for a week?

Reply #11
Paul, what is the year and model number of your coach?
Slim,

Here is a little tip:  If you click on the name of the poster (in the left page margin) it will take you to their profile page.  There, you can often find out what year/model coach they own.  Handy when the info is not included in their signature.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: New starting Batteries, dead after sitting for a week?

Reply #12
Did the batteries go dead, or did your ignition solenoid? Nothing at the gauges makes me suspicious.
1994 U280, Build 4490
Deming, NM.

Re: New starting Batteries, dead after sitting for a week?

Reply #13
Plus one on:  use the trik-l start device to keep starting batteries charged. Ultra TRIK-L-START Starting Battery Charger/Maintainer 
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: New starting Batteries, dead after sitting for a week?

Reply #14
Until the OP tells us battery voltage (digital voltmeter) I suspect there will be a lot of speculation.

Same for possible excessive parasitic draw-- will require an ammeter to get the FACTS. Pull fuses until you narrow down the circuit that is taking excessive power (if there is one).
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: New starting Batteries, dead after sitting for a week?

Reply #15
Paul, much easier to assist if the model, year, etc is known.

Many install a $50 Trik L Start to keep a small charge on start batteries while plugged in or on generator.  Simple install and forget it is there.

Re: New starting Batteries, dead after sitting for a week?

Reply #16
Agree w Brett.  Before the OP worries about charging his engine batteries, he needs to determine the amp draw on the system. There is obviously an underlying problem.  The monitor on my coach shows I only lose 0.03 volts off of my engine batteries every 12 hours. I parked mine 3 days ago and it just now bled down to 12.77v.
Steve DeLange
2005 U320T 40'
Pearland, Texas

Re: New starting Batteries, dead after sitting for a week?

Reply #17
Paul, sorry for your experience. First off, just because your engine won't  start, doesn't mean the start batteries are dead.
1st, take a voltmeter to it, and see what the voltage actually is. If they are down below 11.8 volts or so, then you know you have a draw issue.  Measure it unplugged. Then plug in to shore power and see if there is a difference. If you have some kind of charger another owner installed you will see higher voltage plugged in.
If not,then like others have already said, you need to start finding out what is connected to that battery and seeing what is on while the engine is off. My guess is your radio but there will be others.
Also, on my dash, I have 2- 12 volt outlets. 1 is to the chassis batteries, 1 to the house. A simple plug in voltmeter will tell you what you need to know to properly monitor your batteries from the driver's seat. Won't help you know, but will for the future. Keep the start and the house loads isolated by not using the boost switch.  Make sure you have someway to trickle charge your start bank, either thru the main charger, or a additional charger. AMP-L-START is the big brother to the trik-l-start. $75 bucks usd, or go with the trik-l-start for $35. 
Your inverter/charger might have a 2nd charge circuit. My Victron has a 4 amp charger for the start battery. When AC power is available it will charge the start batteries.
What ever you find out, and decided to use, let us know. I hate threads that one never knows what happened.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: New starting Batteries, dead after sitting for a week?

Reply #18
I killed a similar set quickly by leaving the heais to cross connect both battery bsnks.

I put in a auto/manual magnetic relay that disconnects the banks on discharge
Hey Bob what source/brand?
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: New starting Batteries, dead after sitting for a week?

Reply #19
ML-ACR Automatic Charging Relay Manual 12V [Bulk] - Blue Sea Systems

Replaced the boost switch with the ACR's control.  No indication of status wire ran
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

 

Re: New starting Batteries, dead after sitting for a week?

Reply #20
ML-ACR Automatic Charging Relay Manual 12V [Bulk] - Blue Sea Systems

Replaced the boost switch with the ACR's control.  No indication of status wire ran
Thanks Bob
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country