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Topic: More Alternator woes (Read 1714 times) previous topic - next topic

Re: More Alternator woes

Reply #50 –
Not a car.  Not a car useage.  Long drives versus stop and restart.

Look at a float chart.

 Over 10 here on 13,6 redtops is not unusual. 

Almost the entire rv and Gillig bus co used the 13.6 adjustable voltage LN for a reason
"Riding and rejoicing"
Bob & Susan
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: More Alternator woes

Reply #51 –
Quote from: craneman –
Aren't all the automobiles charging at 14.2 volts under a hot hood. I get 6 to 7 years out of my Costco car batteries.
Yeah, but to play Devil's Advocate, most cars don't travel far enough at any one time to overcharge the battery.
But, 13.6 is also known as the absorption charge, 13.2 is the float voltage to prevent self discharge.  14.4 is the"Bulk" rate and is used only on flooded cell batteries and only up to 80% state of charge.
AGM batteries can be dried out since they start at 90% of the electrolyte needed and rely on recombiners to keep the out gassing "inside."
Gel cells are susceptible to pockets being formed in the gel from the out gassing and I haven't bothered to learn their best charge voltage.
FWIW I have an elderly motorcycle friend whose battery died while watching some racing in Baja, so he cut the top open, pissed in the AGM battery, waited, and got his bike started for the ride out.
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
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Re: More Alternator woes

Reply #52 –
Was he too old to push it????
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: More Alternator woes

Reply #53 –
Quote from: Old Toolmaker –
Yeah, but to play Devil's Advocate, most cars don't travel far enough at any one time to overcharge the battery.
But, 13.6 is also known as the absorption charge, 13.2 is the float voltage to prevent self discharge.  14.4 is the"Bulk" rate and is used only on flooded cell batteries and only up to 80% state of charge.
AGM batteries can be dried out since they start at 90% of the electrolyte needed and rely on recombiners to keep the out gassing "inside."
Gel cells are susceptible to pockets being formed in the gel from the out gassing and I haven't bothered to learn their best charge voltage.
FWIW I have an elderly motorcycle friend whose battery died while watching some racing in Baja, so he cut the top open, pissed in the AGM battery, waited, and got his bike started for the ride out.
I know the numbers as they are set on my inverter charger. And the 12.2  50% discharge. All I was commenting to is the batteries I use in the car last longer than what would seem normal with being overcharged. As far as not driving distances, the family car sits and only runs long distances. Here to Vegas and back for NASCAR I have to keep a trickle charger on to compensate for the parasitic drain between uses. The Jeep toad never goes less than 20 mile trips to the lakes we use it to get to, and usually 50 plus miles.  The short trips at home for the jeep would need the 14.2
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: More Alternator woes

Reply #54 –
In an effort to clear up all this "it's wrong" "it's right" LN Vs Delco-Remy stuff.

I have placed a call to the Delco-Remy tech line and asked the question: if one is driving for a long distance and your AGM batteries have reached full charge. Wont this alternator be over charging them @ 14.3V when AGM's like a fully charged float voltage of 13.6V?

The tech guy said that this will be pushed up to the engineering section about this AGM charging and call me back.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: More Alternator woes

Reply #55 –
Thanks.  The answer would be of interest.

"Riding and rejoicing"
Bob & Susan
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: More Alternator woes

Reply #56 –
Quote from: Caflashbob –
Thanks.  The answer would be of interest.


Yes it will.
And the answer could be in the middle. 

Perhaps I'm off base and correct me if I'm wrong. 

BUT! The manufacturers of dual battery bank RV's could have put on some sort of charge controller to cut alt charging to the batteries and still power coach electric demands. But it also seems that in an effort to sell the RV for a few hundred dollar less. They decided not to.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: More Alternator woes

Reply #57 –
I have my LN alternator set for 13.6v as I use solar for battery charger and it is custom set for AGMs. The long drives we do a couple of times a year hopefully do not do much charging . The batteries were new in 03--2011 and still seem to be doing fine. I also have a n equalizer on each one 100% of time.
JohnH
Coachless, now use aircraft.
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: More Alternator woes

Reply #58 –
Quote from: John Haygarth –
I have my LN alternator set for 13.6v as I use solar for battery charger and it is custom set for AGMs. The long drives we do a couple of times a year hopefully do not do much charging . The batteries were new in 03--2011 and still seem to be doing fine. I also have a n equalizer on each one 100% of time.
JohnH

But why would you need to do all this on a coach with a price point of nearly $400K. I would think that things like battery management systems would be the reason the coach is so expensive.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: More Alternator woes

Reply #59 –
Here is a battery charge curve showing the bulk, absorption and float durations. What most don't realize is the absorption phase takes a LONG time, 6 to 8 hours. The alternator's purpose is to charge after battery use over night, not provide float/maintenance, the coach charger should do that. I think all this fear of excessive charging while driving is over-blown.
Peter and Tammy Fleming and Rosie
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: More Alternator woes

Reply #60 –
Quote from: prfleming –
Here is a battery charge curve showing the bulk, absorption and float durations. What most don't realize is the absorption phase takes a LONG time, 6 to 8 hours. The alternator's purpose is to charge after battery use over night, not provide float/maintenance, the coach charger should do that. I think all this fear of excessive charging is over-blown.
Thanks for that chart Peter. That helps a lot.

As an inexperienced RV owner. It can be a daunting task at times wading through all the info. Is an answer based on fact, urban myth, out dated truisms, Guessing?  And figuring out which is correct without knowing what to even ask (the inexperienced part) is hard and makes one wonder if anything they are doing is correct.

I have noticed that when I'm using the on board Xantrex charger. It stays in accept (absorbtion?) for a very long while.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: More Alternator woes

Reply #61 –
Quote from: Caflashbob –
Factory and Brett here both set the alternator at 13.6 volts at the battery.

13.6 volts is too low to complete the absorption phase and you will not reach 100% charge.
Peter and Tammy Fleming and Rosie
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: More Alternator woes

Reply #62 –
Here is what Borg Warner sent me.

Hello Jerry, One thing I want to advise you to verify is to test voltage at S terminal of alternator with ignition off to verify you are getting battery voltage, to insure the circuit connection for remote sense. Typically AGM carries .2V higher reading than standard. Other than this it is not believed to be an issue for the AGM Batteries
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: More Alternator woes

Reply #63 –
Peter really good point.  I had researched  that,  the Magnum inverter or the solar I have finishes  the absorption great. Mk says up to weekly to get to 100% on their gels is ok.

Must work in general as there are hundreds of posts here with 10-12 year mk gels battery life set at 13.6 alternator and the inverter to finish the charge.

My alternator starts out at the dash lighter outputs at 13.86 after starting the M11.  Within a few minutes starts dropping.

My 13.63 or so is fully charged long drive.  Alternator basically shuts off as the solars 13.6 is running the coach with no other major loads.  Engine loop heats the water. 

Coach is outdoors and the auto  combiner is always on.

I have a 250 watt adjustable load tester coming by boat,  five hours to test an 8G8D to 50% to verify actual condition.

Big heat sink.  Fan forced cooling.  Separate the batteries or test hooked up.  Lab grade.  Separate 12volt power supply needed to run it.  If the group does not show correct amp hours then I will separate them.  And test again.

MK and Lifeline require 1/5th or 1/20th C charging.

We will see how they are holding up.  Who knows.  The amp hours used seems to match the battery voltage at certain SOC percentages.

The load bank/ resting voltage check should match what I see. Hopefully.

Bought the trick inexpensive load tester for another purpose. 

Will report how everything is working.  No ego.  Just what is really going on.

This would seem to work.

250W DC 12V Discharge Battery Capacity Tester Module With DC Electronic Load...



"Riding and rejoicing"
Bob & Susan
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: More Alternator woes

Reply #64 –
Quote from: Caflashbob –
I have a 250 watt adjustable load tester coming by boat,  five hours to test an 8G8D to 50% to verify actual condition.

250W DC 12V Discharge Battery Capacity Tester Module With DC Electronic Load...

This load tester looks great. For our van with 400 AHs I do a make-shift load test using a 300 watt light bulb and monitor inverter amp draw with a clip on amp meter. 300 watts is approx 28 amp draw with inverter efficiency added in. I run the batteries down to 50% capacity on my Balmar SmartGauge and calculate the AH used. 200 AH should be approx 7 hours for the test. I try to do this twice a year.
Peter and Tammy Fleming and Rosie
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B