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Topic: 8.3 cummins need aux batteries? (Read 1525 times) previous topic - next topic

8.3 cummins need aux batteries?

Friend with SOB, 2000 vintage, has 300 hp Cummins 8.3.

She tried to start, pretty cold day for E. Texas, and engine batteries barely got it done.  She worries have to replace them.

I asked if they had instructions, may require the Aux batteries to be on to start that 8.3, but I do not know.

What about it....most likely the engine batteries weak or combination of cold weather and not using the Aux batteries to start?

(she having to learn a lot while husband ill.  I suspect this is in the manual, but I have not seen that yet.)

Mike
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: 8.3 cummins need aux batteries?

Reply #1
Mike,

I don't think you know enough to get comments.  an 8.3 should start in the cold with starting batteries alone, but with an SOB, you don't know what capacity batteries were provided.  Then we don't know how old hers are, how they've been being charged or how the battery cables have been maintained.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: 8.3 cummins need aux batteries?

Reply #2
Hi Folks;

I have had the same problem with my 98 U270, 8.3. Now having said that you need some info as to where I am. I live in central Maine, about 30 miles northwest of Bangor.

I have the coach winterized and covered, do not have indoor storage. I also have it plugged in to a power source. Since I put it in winter storage I have started the engine twice, the second time about two weeks age. Am not taking it on the road due to the heavy use of salt here. I turned the block heater on for about 3.5 hours before attempting to start. Another factor I believe is a problem is the low temps here. That week the temps were in the single digits during the day and often below zero at night.

On my last run the engine batteries would barely turn it over, to get it started I had to use the boost switch. As you all know that puts the house batt. in with the engine batts. It started.

This brings me to this question; Are the engine batteries on a charge circuit as are the house batteries? If not that could explain the low batt. after a month and a half in such cold temps. I have not checked the dates on the batts. but will as soon as I can get to them, snow & ice with 6 to 10 forecast for tomorrow.

Thanks

Re: 8.3 cummins need aux batteries?

Reply #3
The engine batteries will not be charged along with the house batteries unless you turn the boost switch on. That ties the two banks together for better or worse... Meaning, if you lose shore power while the switch is on, both banks can drain down past the point of permanent damage.
Don

This brings me to this question; Are the engine batteries on a charge circuit as are the house batteries? If not that could explain the low batt. after a month and a half in such cold temps. I have not checked the dates on the batts. but will as soon as I can get to them, snow & ice with 6 to 10 forecast for tomorrow.

Thanks
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 8.3 cummins need aux batteries?

Reply #4
I doubt their coach has a trickle charger to the engine batteries.  I think it has not been cranked in about a month when he got injured, will never drive again.  Temps range here 25 - 55.  I am very sure there was/is no heat to the engine before she was trying to start it.

I am just trying to see if it is normal to always use the house batteries  (aux) to start the engine.....that is normal procedure on the ISM that I have.  I think, just think, it is not normal on the 8.3.  So her quick and easy answer was to buy batteries but the budget would be better if it really required, not just done as she.  There is a battery place in Nac we could take it to, have load tested.

I need to do some homework as some wrote, will see if I can determine the age of the batteries and if there is a trickle charger from shoreline.  The coach is an American Tradition 2000.  The batteries were supposedly checked at purchase but I do not like assumptions on used coach representations.....that may have just been, oh it cranks right up.  I do not even know what kind of batteries.

I guess I may go over and turn on the aux switch for a day, see if the batteries improve.  Good idea on that Don or whomever wrote that.

I can foresee lots of help needed if, as Bret W. wrote me one time, it is a couple desperate to keep on the road.  She drives well, through downtown Houston to medical, and two other trips.  But is dependent of RV friends on virtually everything else.  As Don H. told me one time, a steep learning curve that probably is not appreciated (expected, understood)

thanks guys,  and blessing of the New Year,

Mike
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: 8.3 cummins need aux batteries?

Reply #5
Michael, I just reread the first post and noticed that it is an SOB you are asking about... Not sure then about the charging system, but I will typically use the boost switch if it has been sitting for more than a few days, especially if it is cooler than shirt sleeve weather. Then again, our house batteries (there are only two) are scheduled to be replaced soon. But even when we first got the coach, the first couple of cranks were a bit reluctant even though it would catch pretty quick.
Don
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 8.3 cummins need aux batteries?

Reply #6
Yup, most likely a combination of issues:  discharged chassis batteries (likely with no charge from shore power), cold temperatures and failure to use boost switch.

BTW, you can't have too much battery to start, so using the boost switch is a good idea all the time.  Remember with all modern diesels, you are not only turning over the motor, but also heating up a LARGE intake manifold grid heater. 

Do NOT use ether with a modern diesel, as ether and red hot heater grid don't play well together.

Brett
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: 8.3 cummins need aux batteries?

Reply #7
Norm,

CLean terminals, good batteries and a trickle charger (I prefer a dedicated battery maintainer to a trip-l-start or echo charger) Start batteries should start engine and spin pretty well if you have had on the engine heat that long. Most probably that you do not have a trickle charger.

I have ISM and using boost is fine per James Triana on every start, but once I cleaned the terminals, made sure they were tight and had three good charged batteries, never a need at all.

John S. has gone further with wiring mods to lessen the amperage drop to the starter, but I haven't found that to be necessary.

After having trouble with both an Echo Charger from Xantrax (Intermittent) and two echo chargers (both failed at around a year) i researched battery tender and battery minder products.

Settled on this one as a combination maintainer and desulfator for all three red-top house batteries - available at Amazon and elsewhere, here is the company web link:  http://batteryminders.com/12-volt-maintenance-charger-desulfator-1500

good luck, but I suspect this will solve most issues. Remember, you are heating your engine, but not your batteries, so in this cold your batteries, even if fully charged are operating far below capacity
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: 8.3 cummins need aux batteries?

Reply #8
thanks all, think have a plan to help her......they traded that HR Bret that you helped them with, got this American Tradition.  It seems a better coach, maybe not by brand.....I have no idea on that.....but due to previous care.

I guess seldom do people buy their last one first

Mike
Mike
2001 U320 4010 Build 5878 (Gus)
Wrangle Unlimited Toad
Nacogdoches

Re: 8.3 cummins need aux batteries?

Reply #9
Mike, we have the 8.3 engine with two Optima Red Top start batteries. The engine will start from the start batteries in temperatures down to about 30-35F. Starts are much snappier with the Boost switch engaged. We almost always use the Boost. If the temperature is below 35F, leaving the block heater on for several hours will make starting much easier.

For a few months this year, starting from the start batteries was very sluggish. I bought a relatively cheap battery tester. It showed one of the Red Tops to be good and the other to utterly fail under load. I replaced one battery and starting is much better.

Norm, I concur with Fiedler's recommendation. I use the Power Tender Plus, <http://batterytender.com/power-tender-plus-12v-at-5a.html>;, a 5A smart charger, to maintain the start batteries.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: 8.3 cummins need aux batteries?

Reply #10
When I became a new FT owner five years ago, I was advised to always use the boost switch when starting thw the engine.  I soon discovered I could start using chassis batteries alone,  but only if the coach had been driven in the past day or two.

It turns out one of the agm batteries had a shorted cell. After swapping out that battery and installing a battery tender it always starts well without boost.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: 8.3 cummins need aux batteries?

Reply #11
Rather than spending a lot of money on start batteries and still have trouble like above, why not buy something like a Autozone Duralast? I replaced the three start batteries our Detroit takes when we took delivery 4 years ago. Just under $300 for the three. It spins like a top even in winter down in the teens and without using the boost switch. If a couple of group 34 don't do it for your 8.3, get a couple of commercial 31 series. I noticed other Cummins owners have also made the switch to 31s. With good connections and cables, the Cummins should also spin like a top.

When one battery has a shorted cell, it's always best to replace both (or three) rather than just the bad one. While you may not notice the mix of one new and one 4 or 5 year old battery in summer, it may be very noticeable in winter. I can understand if each battery is close to $200 but a battery with a 7 year warranty under a $100 is a bargain. With the seasonal use that many RVs get, a lot of batteries never get close to their designed lifespan. In the past, our Duralast batteries have gone well past the seven year mark. Duralast batteries are sold a Autozone stores and are made by Johnson Controls. They have an excellent reputation.

If your Diesel does not spin at normal speed when cold, go back and feel the cables and all terminals after cranking. If warm or hot, your problem lies in the connectors or cables. Another reason I like to have the extra ground cable to a chassis ground close to the starting batteries. Heavy duty terminals with bolts on both sides are also available. Slow cranking means lower compression and less heat to ignite the diesel fuel when it's injected.

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

Re: 8.3 cummins need aux batteries?

Reply #12
Tim & J.D.

I use something similar to that on my riding lawn mower, keeps the charge up.

As soon as I ca get to them I want to check the dates, we purchase the coach last Jan and I don't think it has been in weather like this.

The SAM's club in Bangor just started carrying AGM's and I believe they are 31's with a Duracell label on them, not sure of the price. Would they be a good replacement for the start batteries id they should be changed?

Norm

Re: 8.3 cummins need aux batteries?

Reply #13
Norm,
What are your house batteries?
If Gel, use Optima Red Top Starting Battery
8002-002 Part No. (Batteries Plus)
34-1050 Model No.
1000 CA
800 CCA
104 RC

Batteries Plus store

STORE ADDRESS:
11 Bangor Mall Blvd
Bangor, ME 04401

PHONE NUMBER:
207.947.8882

STORE HOURS:
Mon—Thurs:8:00-8:00
Fri : 8:00-8:00
Sat: 8:00-7:00
Sun: 10:00-5:00

STORE CONTACT:
Jack Reilly, Manager

FAX NUMBER:
207.947.8884

I'm going on 12 years w/mine.
Always use boost to start, go right back to non-boost after start.  Spins like a top at 180K +, down to 32F.  Below 32F, use block heater overnight prior to start.  Good to well below zero then, with proper battery operation/treatment.
Neal
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Neal (& Brenda) Pillsbury
'02 U320 SPEC, 4200, DGFE, Build #5984
'04 Gold Wing
'07 Featherlite 24'
'14 Jeep Grand Cherokee Summit
MC #14494
Exeter, NH & LaBelle FL
Quality makes the Heart Soar long after Price is Forgotten

Re: 8.3 cummins need aux batteries?

Reply #14
Neal;

My house batteries are Duracell wet cell type, not Gel or AGM. The engine batteries are Deka, don't know the model or age.

Right now would have to dig out 18 inches of snow to open the compartment. Thanks for the info I know where Battries Plus is. SAM's club in Bangor did carry the red top at one time but no longer. I am planning on run in place today, won't take it on the road due to the heavy use of salt. Have 6 to 10 coming later today so I can still get into the coach without digging yet.

Would it be safe to leave the boost switch on to keep the engine batteries charged?

Norm

Re: 8.3 cummins need aux batteries?

Reply #15
If Gel, use Optima Red Top Starting Battery
8002-002 Part No. (Batteries Plus)
34-1050 Model No.
1000 CA
800 CCA
104 RC

Would someone educate me on CA, CCA and RC

What would this battery be rated in "Ampere Hour" capacity?

All batteries are now rated in CA, CCA, RC

Why, living in Texas, would I be interested in CA,CCA or RC.

1993 U300, 6v92
build 4366
USAF retired, Flight Engineer, C124, C130
 ATP, A & E.  & ex AI

Re: 8.3 cummins need aux batteries?

Reply #16
Bill,

Because you take your U300 to other destinations, other altitudes, other temperatures.

Here is an excellent PDF called "battery 101". Answers any questions some of the newer members might have about almost any battery construction, types, etc. Codes are toward the bottom of the PDF. http://www.autoshop101.com/forms/hweb3.pdf

Norm,

Remember, the boost solenoid draws .7 amps at idle and gets hot to the touch after about an hour even if no juice is going through it. I just run a big zip cord with a set of clips at the ends between the two sets and that keeps both battery exactly the same without the current draw. With the main cables disconnected, the batteries will go all winter without discharging.

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

Re: 8.3 cummins need aux batteries?

Reply #17
Good quote on comparing AH and CCA: "The definition of the Cold-Cranking Amperage (CCA) of an automotive battery is the amount of current a given battery can deliver for 30 seconds at zero (0) degrees F without dropping below a specified cutoff voltage (manufacturer-specific, but usually 10.5 volts).

The Amp Hour rating tells you how much amperage is available when discharged evenly over a 20 hour period. The amp hour rating is cumulative, so in order to know how many constant amps the battery will output for 20 hours, you have to divide the amp hour rating by 20. Example: If a battery has an amp hour rating of 75, dividing by 20 = 3.75. Such a battery can carry a 3.75 amp load for 20 hours before dropping to 10.5 volts. (10.5 volts is the fully discharged level, at which point the battery needs to be recharged.) A battery with an amp hour rating of 55 will carry a 2.75 amp load for 20 hours before dropping to 10.5 volts."

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

Re: 8.3 cummins need aux batteries?

Reply #18
.......................Why, living in Texas, would I be interested in CA,CCA or RC.....................
Hi Bill,
Pierce has given us good info.
Obviously, AH capacity in the house batteries is what we need for meaningful comparison.....for house batteries. 
In starting batteries, however, how much "Ooomph" the starting batteries have, right out of the starting gate, is what is important, especially at lower temperatures. 
When a Cummins (or any truck service) center tests starting batteries on an 8.3 Mechanical, they are looking for 2000 CA combined capacity (corrected to actual temperature.....they test each battery separately).  Mine are still showing that, just barely, at 12+ years of age.  New they were on the order of 1300 to 1400 CA, each, at 70F.  Obviously, the test doesn't include (doesn't want) the house batteries paralleled in through the Boost Switch.  Using the Boost switch, I'm still well in excess of the 2000 CA combined capacity Cummins expectation.  The house batteries through their longer leads, boost solenoid contact area current limitation, instantaneous current limitation, etc. contribute only a fraction of what the starting batteries are providing, even with the boost switch closed.
Hope this helps, have a Happy New Year!
Neal
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Neal (& Brenda) Pillsbury
'02 U320 SPEC, 4200, DGFE, Build #5984
'04 Gold Wing
'07 Featherlite 24'
'14 Jeep Grand Cherokee Summit
MC #14494
Exeter, NH & LaBelle FL
Quality makes the Heart Soar long after Price is Forgotten

Re: 8.3 cummins need aux batteries?

Reply #19
...............My house batteries are Duracell wet cell type, not Gel or AGM...........................
...............Would it be safe to leave the boost switch on to keep the engine batteries charged?.....................
Norm,

To add to Pierce's info,
MOST IMPORTANT: stay with one battery type for start and house batteries and be sure to set (or have someone else set) the alternator and the battery charger to the manufacturers' optimum setting for the chosen battery type.

There are pluses and minuses to wet, Gel and AGM battery types.  There is much info on this forum and on the internet, as well as from all the manufacturers, on these pluses and minuses. 
From my experience, what many people lose sight of and make costly mistakes on, is that with one alternator, one battery isolator and one battery charger, if you mix battery types, you will compromise one, or the other, or BOTH battery banks through under or overcharging. 
If you know what you are doing and either manually control, or install separate monitoring/charging systems, you can take advantage of the separate battery designs, but if you need or want simplicity, don't mix! KISS, KISS!
Your current problem may be related to that, but I suspect that it is more likely that the DEKA engine batteries (AGM's?) have lost their charge.  AGM's will be damaged from deep discharge for extended periods and recovery may be less than 100%.

To reanswer your second question, if you have reliable shore power, by all means leave the BOOST switch closed to allow the starting battery bank to be charged and stay charged.  When parked, if I am nearby or checking the coach frequently, I leave the boost switch closed most of the time, even though I have installed a Trik-L-Start system.  As others have said, though, with the boost switch closed, you are vulnerable to something going wrong and then BOTH battery banks becoming fully discharged.
Examples of the "something going wrong"?
    • Loss of shore power
       
    • Battery charger off (and you don't recognize it)
       
    • "Cooking" a mismatched battery bank type through continuous overcharging
       
    • A battery in either bank failing, like developing a shorted or open cell, which leads to depletion of both banks
       
    • etc., etc.
Hope this helps...send me a PM if I can help further,
Happy New Year and don't let that cold and snow migrate south!
Neal


 
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Neal (& Brenda) Pillsbury
'02 U320 SPEC, 4200, DGFE, Build #5984
'04 Gold Wing
'07 Featherlite 24'
'14 Jeep Grand Cherokee Summit
MC #14494
Exeter, NH & LaBelle FL
Quality makes the Heart Soar long after Price is Forgotten

Re: 8.3 cummins need aux batteries?

Reply #20
Hi Guys;

Boy O Boy, this is sure a lot to digest.

Not going to start today snow has begun.

I did have a problem this past summer, one of the 8D wet cell house batteries exploded. These were in the coach when I purchased it in Jan. I replaced both 8D wet cells they were Interstate dated 2010. Do not know if engine (Deka) batteries are the same, wet cell. Now having said that I think I will not close the boost switch until I know what type they are. When I find out I will let you know. Don't much feel like going out in the snow. This is supposed to last into Monday. After I finish clearing the driveway I will check it out.

Thanks
Norm

Re: 8.3 cummins need aux batteries?

Reply #21
When batteries get too much voltage and are overcharged as some OEM converter/chargers do, they get warm, the water is evaporated leaving an open area from the caps down to the plates or even beyond. This fills with hydrogen and then more hydrogen is released into the compartment. The hydrogen mixes with the air and at the first spark, explodes. The flame from the explosion continues through the cap down into the space below and blows the battery case apart. This is frequently seen when a battery charger is disconnected from the battery terminals after charging for a while. Having a smart charger with the voltage set for your particular battery is the best way to avoid this. Most battery manufacturers post the proper bulk, absorption, and float/maintenance voltage online. Some batteries may also allow a equalization, AGM and Gel types usually don't. You can then set the charger output voltage for maximum battery life and minimize any incidents. Occasional electrolyte level checking is still necessary depending on type of battery.

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

Re: 8.3 cummins need aux batteries?

Reply #22
Mike, all good advice from everyone. My ISC 8.3(2 Optima red top battery's) has never liked cold weather if below 40 I turn on the block heater the night before I leave if I'm plugged in and use the boost sw makes the Cummings happy on cold start. Any good truck electric shop can check the starting charging system. Worn starter bushings, bad cables dirty terminal connections both on the positive and ground side, all of these can cause a little voltage drop and together add up to a no/slow start. If you replace the battery's you can still end up with a slow start. If you are good with a volt meter it's easy to check, all voltage drop checks have to be done under a load (while cranking). A good start is to clean all connections both at the battery ends and the starter, and load check the battery's.
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: 8.3 cummins need aux batteries?

Reply #23
Bruce,

Just a note:  Unless ambient temperatures are way below zero F, no need to run block heater more than 2-3 hours. Most are 1200-1500 watt heaters.  That heats that "hunk of iron" pretty quickly.
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: 8.3 cummins need aux batteries?

Reply #24
I have started many Diesel engines at zero degrees without preheating.

Extended crank time was explained as ok to me long ago.  30-60 seconds?  No problems I ever heard of long ago.

Takes a while to build the heat up in the combustion chamber?

We were skiers much younger and dry camped at altitude in the winter many times.

Did use the old ether starts a lot.

Or the block heater if running the gen long enough in advance of use

Bob
"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