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Topic: Engine Batteries (Read 899 times) previous topic - next topic

Engine Batteries

My AGM coach batteries appeared to be having a hard time starting the coach a few weeks ago, but all appeared well after a trip.
I do not think the batteries have been super strong since I bought the coach April last year, if it sits for a week it's slow to turn over, on a trip and it starts a bit quicker, I just assumed it was the nature of this Cummins engine.
To raise the coach yesterday, starting the engine was sluggish so I decided to put the charger on the batteries and it began by showing the battery had 25% charge and  running the desulfation program.
This is surprising, the batteries are two years old and I Installed a Trick-L-Start Last year to maintain the batteries (which may not be doing it's job). Coach is on shore power 24/7.
Twelve hours later the AGM charger is still in the desulfation mode and not yet charging the batteries. Think they may be dead??
QUESTIONS:
1) Are the batteries shot?
2) Am I better off to buy a regular battery for half the price of the AGM type battery?
3) How many Cranking amps should they be? Coach has two batteries
Thanks
David
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

Life is made to enjoy, the Foretravel helps!

Re: Engine Batteries

Reply #1
Are you sure your shore power circuit is always on?  Is the battery charger in your inverter always ON and powered?  Is the Trik-L-Start connected correctly?  Does it show the correct LED when charging and/or maintaining?  The Trik-L-Start will only work when the coach (house) batteries are being actively charged.  It "robs" a small bit of the charging current to maintain the start batteries at full charge.  It is not designed to recharge badly depleted batteries.

Our coach is always plugged in to 50 amp.  I have had a Trik-L-Start installed for 6 years.  It has never failed to keep our start battery bank fully topped off.

I believe it is very helpful to have two inexpensive volt meters mounted in your coach.  One meter shows chassis (start) battery voltage, the other shows house battery charge.  By simply glancing at the meters you can quickly ascertain the relative condition of both battery banks.  If one bank is reading lower than the other, it raises a red flag.  I have my meters mounted on the dash.  Every time I walk into the coach I can see the meters.  Cheap insurance to protect expensive batteries.

What did you do to your coach today VI
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: Engine Batteries

Reply #2
Am I correct in thinking that plugged in to shore power means The house batteries are being charged?
The only thing I have off is my inverter switch, should it be on to charge batteries?? Thought not?
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

Life is made to enjoy, the Foretravel helps!

Re: Engine Batteries

Reply #3
Irish wrote: "To raise the coach yesterday, starting the engine was sluggish so I decided to put the charger on the batteries and it began by showing the battery had 25% charge and  running the desulfation program."

How big is the battery charger you're using?  Remember, only about 65% of the amp hours you are providing for the battery becomes battery state of charge.

Irish: "Twelve hours later the AGM charger is still in the desulfation mode and not yet charging the batteries. Think they may be dead??

My suspicion is that your battery charger is dead.  Do you have a 10A dumb charger handy?
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Engine Batteries

Reply #4
Am I correct in thinking that plugged in to shore power means The house batteries are being charged?
The only thing I have off is my inverter switch, should it be on to charge batteries?? Thought not?
Depends on what equipment you have.  Do you have a inverter/charger OR do you have a inverter AND a (separate) charger/converter?

I have a combination inverter/charger.  My control panel allows me to turn on the inverter, OR turn on the battery charger, OR turn on both.

Because we have a residential fridge I leave BOTH inverter and battery charger (functions) turned on all the time.

SO, in my case, plugged in to shore power does indeed mean my house batteries are being charged.
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: Engine Batteries

Reply #5
Depends on what equipment you have.  Do you have a inverter/charger OR do you have a inverter AND a (separate) battery charger?

I have a combination inverter/charger.  My control panel allows me to turn on the inverter, OR turn on the battery charger, OR turn on both.

I leave BOTH inverter and battery charger (functions) turned on all the time.

SO, in my case, plugged in to shore power does indeed mean my house batteries are being charged.
And at the other end of things, we don't have a house inverter and use a Progressive Dynamics PD9160 3-stage power supply to charge the house batteries and provide 12VDC when connected to shore power.

FWIW, my deferred maintenance list has more items checked off than left to do so the question of a new 8-D start battery was raised recently.  I'm going to wait for my neighbor with the pickup truck* to finish his travels, but the new 8-D will also arrive with a new PD 9260 dedicated to the 8-D's maintenance.  I consider the PD 9260 to be money spent once, backup to the engine driven alternator, and a way to charge the chassis battery after I leave the lights on.

*The battery store will help me get the battery into the back of the Siata but I can't figure out how to get it back out again.  Hence: Truck.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Engine Batteries

Reply #6
The battery store will help me get the battery into the back of the Siata but I can't figure out how to get it back out again.  Hence: Truck.
You could always hire a couple young strapping footballers for 30 minutes of moderate physical labor.  $20 each would do it where I live.
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: Engine Batteries

Reply #7
My converter switch Has an on/off,
I have it off - am I not charging my house batteries, I have had no problem with them that I know of
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

Life is made to enjoy, the Foretravel helps!

Re: Engine Batteries

Reply #8
Sounds like either your Trick-L-Start is not working or you have a draw on the chassis batteries that exceed its charging capacity.

Pull out your digital voltmeter and check them.  Let us know what readings you get and under what conditions.

Yes, one or more batteries may be bad, particularly if they have frequently been deeply discharged.  A good idea to fully charge them, then have each battery individually load tested.
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: Engine Batteries

Reply #9
I have had trickl chargers that show a green charging light and have zero output.

"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: Engine Batteries

Reply #10
My converter switch for not has on/off
I have it off - am I not charging my house batteries...
I'm sorry - your statement makes no sense.  Try again?
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: Engine Batteries

Reply #11
I am ASSUMING he has the ON-OFF switch on his INVERTER/CHARGER off. 

That should have no effect on the charging function of the inverter charger/ it should charge with switch on or off.
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: Engine Batteries

Reply #12
I am ASSUMING he has the ON-OFF switch on his INVERTER/CHARGER off. 
That should have no effect on the charging function of the inverter charger/ it should charge with switch on or off.
Like I said up above, depends...  Does he have a inverter or a converter?  My mind reading ability is somewhat weak this morning.

Reply #2 he says inverter.  Reply #7 he says converter.

My (Magnum) inverter/charger has a separate switch for each function.  If I have the inverter (function) turned off, the battery charger does not work unless I have the charger (function) turned on.  Both switches off = nothing works.  See remote panel image below.

I don't know how the OP's equipment works.  Would help if he would tell us exactly WHAT equipment he has on his coach.
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: Engine Batteries

Reply #13
You could always hire a couple young strapping footballers for 30 minutes of moderate physical labor.  $20 each would do it where I live.
That's how I got the 4D batteries i purchased last year out of the through bay and into the battery compartment.  But there's only one young guy here for hire.  The average age here is somewhere around death.  Two down since we started living here.

Hey Irish!  What brand and model is your inverter/converter?
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Engine Batteries

Reply #14
Agree with Bob

I had a trickle charger (trik L start brand) that showed a green charging light despite the fact it was NOT charging.
Killed two sets of start batteries before I figured that out Solar and redundant trickle starts now in place. Plus I have a battery minder that works when plugged in, which it is while stored I know overkill and 10 better ways to do it, but works for me
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: Engine Batteries

Reply #15
Solar was one half of the fix for me.  Added a auto battery  combiner. 

2 sets also
"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: Engine Batteries

Reply #16
I know overkill and 10 better ways to do it, but works for me...
Sounds good, BUT, are you protected against a EMP attack?
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: Engine Batteries

Reply #17
I figure a combiner, and boost sw, on board, solar, engine alternator, and a Jeep with long jumper cables my battery charging is covered.
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: Engine Batteries

Reply #18
When I bought my coach at had a trickle start on the optima batteries. When the optima's died one of the things I wondered was was the trickle start doing its job? it was the old model for lead acid batteries anyway so I replaced it with a trickle start agm. And since I installed it I've never looked at it so it couldn't tell you if it's charging the battery or not but Cummins m11 starts right up with a quick twist to the key so I'm not worried about it right now. I do not have the ability to charge my start batteries from solar, nor do I have the ability to charge my house batteries from my alternator. Something I definitely like to change next year.
But I can't say enough about the Odyssey batteries that I put in. Think they are PC 2100 or something like that. Two of them do the job of three optimas and better.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Engine Batteries

Reply #19
The combiners controller installs where the boost switch was before.  At least the blue seas one.

Uses the same wires.  Just no panel light up to show what's the status,

That's not a problem as you can hear the unit combine from the drivers seat. Click noise
"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: Engine Batteries

Reply #20
The combiners controller installs where the boost switch was before.  At least the blue seas one.

Uses the same wires.  Just no panel light up to show what's the status,

That's not a problem as you can hear the unit combine from the drivers seat. Click noise
Don't the combiners disconnect the house batteries during start up? If so the boost capability has been eliminated.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Engine Batteries

Reply #21
Good question.

The remote panel has off, auto and combine on it.  Locked out for safety if in the off position.

On the combiner itself is a lug that if connected to the starter relay which is adjacent to the combiner then the combiner will auto disconnect the banks when the starter is engaged.

If you do not hook up the starter sense lug and the batteries are under charge both banks will start the engine.

You can manually connect he banks at the remote panel bypassing the starter disconnect sensing wiring

The starter engaged  disconnect is so the start batteries true condition is judged on every start cycle.

As far as I understand this all new coaches use combiners.

We decided that it was not worth the effort to run a third wire to show on the control panel areas that light up to confirm the operations of the combiner.

Works great and is audible at the steering wheel when the magnetic connections are made or released.

I keep two .00 volt meters plugged in at the dash and their  voltage displays confirm the combiners operation.

No brainer with enough solar and the combiner.  100% reliable



"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: Engine Batteries

Reply #22
Don't the combiners disconnect the house batteries during start up? If so the boost capability has been eliminated.

Check the data sheet.  I was looking at one for the previous rig and it could be connected to my boost switch for starting.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.