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Topic: Starting Battery Issues (Read 914 times) previous topic - next topic

Starting Battery Issues

I'm looking to remedy my starting battery issues.  I didn't have the money to deal with it right when I got the coach but the situation has weighed heavily on my mind and if we're not careful we can't start the coach in certain situations.  It's the normal M11 ISM engine a 320 has.  The tray has a 4d battery in it which the seller of the coach replaced with a new one when I was buying it.  It still can't start the engine without boost.  It has the thick (4/0?) cables coming to round/spade connectors.  Those go to spade/post adapters which look vaguely like this.

http://lestoilesroses.net/wp-content/uploads/2015/02/electrical-wire-connectors-marine-battery-cable-burndy-lugs-remote-battery-jumper-terminals-best-battery-terminal-connectors-wire-terminals-and-connectors-auto-battery-replacement-auto-battery-terminal-adapter.jpg

So I measured the internal dimensions of the tray and I was surprised to find it to be 9 3/4" wide and 21" long which seems to preclude a set of 3 group 31 or 34 batteries.  I'm not sure what to make of this.  Any ideas?

Re: Starting Battery Issues

Reply #1 –
I installed 3 - 900 CCA wet cells from Costco. With there warranty I will probably never pay for those start batteries again.
M11 spins like a top, no boost required.
Nothing fancy, it just works.
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: Starting Battery Issues

Reply #2 –
You don't by any chance recall the size class of battery you bought do you?  I can only assume I must have mismeasured or something but I don't think so.  I don't have a costco membership but it seems like a good idea since I want to get a generator through them as well.

EDIT: Looks like 900CCA is group 24 which are smaller batteries in terms of their total cranking before dead time.  If that's what it comes with, that's fine.

Re: Starting Battery Issues

Reply #3 –
Starting and house batteries are discussed at length on this forum as well as on Barry's web site.  We use the Dekka East Penn 8a8d AGM for both - ......No boost....FWIW.

 Nominal Voltage: 12V
 Amp Hour Capacity @ 20 hr rate: 245 a/h
 Reserve Capacity @ 25 amp discharge rate: 517 mins
 BCI Group Size: 8D
 Marine Cranking Amps @ 32* F: 1,800 amps
 Cold Cranking Amps @ 0* F: 1,450 amps
 Weight: 158 lbs
 Length: 20 3/4 in.
 Width: 11 in.
 Height: 10 in.
 Terminal Type: AP
Scott & Carol Seibert
2001 42' double slide U320 - Sold
Previous - 2002 36' U320

Re: Starting Battery Issues

Reply #4 –
Oh I've been searching around before posting ;)  A lot of the information isn't that conclusive.  You're the first person to indicate a single 8D is enough battery.

Re: Starting Battery Issues

Reply #5 –
The ultimate "authority" is your engine manufacturer-- Cummins.

They have minimum CCA's for each engine family.  Get at least their recommended minimum and use boost when starting.  Can't have too little voltage drop with engaging engine intake heater and/or starter.
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: Starting Battery Issues

Reply #6 –
I would think that a 4D battery would be very small for engine starting in these diesels.  I see 8Ds as a standard battery.  Did the dealer or PO remove an 8D and replace it with a 4D.  Measure the btray and I will bet that it will hold an 8D with no problem.
List of Common Battery Case Sizes | BCI Group Numbers


Gary B

Re: Starting Battery Issues

Reply #7 –
Quote from: Lon and Cheryl –
I installed 3 - 900 CCA wet cells from Costco. With there warranty I will probably never pay for those start batteries again.
M11 spins like a top, no boost required.
Nothing fancy, it just works.
Three 34 or 31 series or two 8Ds are the ticket. Less may work fine in summer but in the dead of winter and high altitude where the air is thinner...

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

Re: Starting Battery Issues

Reply #8 –
I am not sure what might be considered "conclusive" with regards to batteries.  Seems like it should be easy - Engine requirements then buy.  But many choices and opinions muck up the water. 

Many folks here prefer 3 Optima style/size batteries, many prefer a single 8a8d, some are moving into the new Ni-Cad tech.  I think it's kinda like pizza - some like sausage and some like pepperoni.  Many purchase from Costco or in our case from O'Reillys.  O'Reillys purchases from Penn Mfg one of the best battery manufacturers.  Opinions differ.  I think  most batteries are made by a small number of manufactures and different decals are applied when sold.

Technical Help - Batteries

You may have read these but I thought I would post this link anyway.

I do not think that any one here will TELL you what to purchase to start your engine or to use as house batteries.  You must make your own decision based on what you think is right, what your needs are as well as your budget.  Brett said:  Mfg. recommendations.  We made our decision based on a number of recommendations from forum members and comparisons of mfg. specifications. 

I would certainly defer to Brett's opinion as he has vastly more experience than I when it comes to anything motorhome related.  ;D
Scott & Carol Seibert
2001 42' double slide U320 - Sold
Previous - 2002 36' U320

Re: Starting Battery Issues

Reply #9 –
Anyone know anything about these for starting batteries?
      Staab Battery Co Group 31P
Specs and price look good.
The selected media item is not currently available.

Mark & Mary Benko
Former coach: 2005 U295 3823
Jeep Cherokee, Honda Fit

Re: Starting Battery Issues

Reply #10 –
After you have done all the obvious things like clean every terminal end and made sure that the engine ground is good try charging the battery fully and see how it starts.  It could be that you have a battery that is borderline and the parasitic draw by the ECM etc is running it down just enough to prevent the engine cranking high enough.  A M11 should crank at 150 RPM to start.  It's minimum CCA is about 600 on a nice warm day.  A 4D has about 1000 CCA at 0 deg.  In theory it's should start but like all theories there are exceptions.  I would use a 8D (about $230) or three Group 27 or 31 whichever will fit (total $300).  You then will have in excess of 1400 CCA.

If you want to check on the battery age look for a small round sticker that will have something like 5/15 or so.  That's the month and year of manufacturer.  Not completely reliable as it's been known for old stock batteries to be re-stickerd at the distributors.  :o

Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: Starting Battery Issues

Reply #11 –
Most of the AGM's will have an embossed date on the edge of the top section of the battery case, usually in a place where you cant read it til you take battery out though.
Gary B

Re: Starting Battery Issues

Reply #12 –
I really believe that the 4d should be able to start the coach in warm weather.  It can't even get it cranking at all.  It charges up fine but I haven't load tested it yet.  I am going to get a tester from Harbor Freight and see what it does.  I literally saw the brand new 4d going in when I bought the coach and the brand new 4d couldn't crank it.

I find it odd that the boost switch really helps get it moving.  I mean the boost wiring is long and not very thick.  I do think I should redo the terminals on the battery entirely and see if that helps. 

My mom has a lead on Deka 8D gel's for $475 or so.  That's a pretty good deal by today's numbers.  I asked her to check pricing on AGM's as well.  Does anyone know if the prosine 2.5 in gel mode will adequately charge an AGM bank?

Re: Starting Battery Issues

Reply #13 –
Quote from: piku –
Does anyone know if the prosine 2.5 in gel mode will adequately charge an AGM bank?

They recommend the flooded setting for AGMs.  That said, our '03 originally had gel house and AGM start batteries and the gel setting worked "ok".  Our start batteries got weak after 3-4 years (coach wouldn't start without Boost).  We are now on AGM house/start with Prosine on "Flooded" and our start batteries are 8 years old and still turn the beast over without boost (we do use a Trik-L-Start).
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Starting Battery Issues

Reply #14 –
Piku, have you checked the voltage drop from the terminal to the wire at each cable connection to the starter both ground and positive. This must be done under a load(starting) . Cables and terminals can look new but have high resistance causing a voltage drop. Redneck quick check attempt to start a couple of times, then quickly put your hand on each connection. If you find one warm or hot to the touch there is a problem.
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: Starting Battery Issues

Reply #15 –
The issue is that black splitter box.  I think one 4 d is a bit light though. This issue was discussed a number of years ago. 

FT used a star washer for the ground on a painted rail.  Go take it off brush it and put on a flat washer to increase the ground.

Then consider running a second cable directly to the starter and put it on behind the first one. This will avoide the voltage drop from that old splitter box and see if this helps.  If not, then add another battery or go with the three batteries like I have in and how ft set it up.  Also there is a hard start upgrade for your ECM too. 
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon
 

Re: Starting Battery Issues

Reply #16 –
John is right on with the ground cable advice.  My 98 U320 had a hard time turning over when I first hit the starter and the current draw is very high.  New start battery made no difference, but boost always really spun it over.  Finally a friend told me that is a common issue on coaches of that vintage and the problem is the poor ground path.  Last year I had a separate big ground cable installed directly between the batteries and the starter and it made a HUGE difference, really fixed that problem.
BJ Holden
'98 U320 36'
Motorcade #16754