Howdy -
I'm trying to be frugal with my new battey purchases, and the starter batteries have me perplexed. I have an 8v92TA, and I currently have 2x 8D 12V batteries with a Vanner system. Each battery spec's at 1380CCA. The 8D's are rediculously expensive. Given that my engine starts on the first revolution, can I get by with 2x 31 size cells with 800-900CCA? What's the minimum CCA to get that beast turned over?
Chris.
I imagine that you can, but i wouldn't do so.
On the other hand, i have moved several busses around that have 8v71,s and the 6v71, and 671, and some cummings, cats and probably a hundred excavators and backhoes with one or two group 24's depending on the voltage.
Not something i reccomend for over the road use..
I can start my 6-71 in the fall with one group 31. I figure 2 31s would probably start you just fine.
O'Reilly has 1000 CCA (1200 CA) Group 31s for only $110, and a higher-capacity one for $130. When my present 8Ds die (one of them is not healthy), I'll use Group 31s instead. Their lower Reserve Capacity won't be a problem because I'll eventually tie my house batteries to the starting batteries for emergency use. I decided to use smaller cheaper lighter Group 31s because I used the 8Ds' space for the poo tank, and the only other space for my starting batteries now is not big enough for 8Ds. When I bought my bus we started it on a cold December day in Fresno CA after it had sat for several months, and one Group 31 started it without a problem.
However, if you're in a colder part of the country, my experience may not be relevant! YMMV etc.
John
Our Eagle came standard with 3 group 31 batteries.
I am of the school where more is better. As batteries age, they loose some of their capacity. They loose some of their capacity when cold. Those can be additive.
If you tired to start your engine at low temperatures, you might have an issue with 2 group 31 batteries.
If you were to loose prime or had some other issue, you would not be able to crank the engine very long with 2 group 31 batteries - especailly if it is cold or the batteries are old.
I just got my flyer from our local IHC truck dealer and they had group 31 batteries on sale for less than $65. I have seen them on sale there often.
Jim
With a 8v92 and the 42MT Delco stater it takes 1250 CCA amps for a 24 volt system (double for 12 volt),the MT 50 that some 8v92's have they are 1800 CCA just remember CCA are for a few seconds only low amperes or low volts will kill a 42MT or 50MT starter and those are not cheap or easy to change but we all do it different, 4 G31's would be my choice for 24 volt if changing from the 8D's JMO
good luck
I own a GMC P8M4905A Buffalo 8V/71 and it has 2-8D batterys in series for a total of 24 volts DC.
I just installed 2 new 8D's and it cranks the first try within a half a turn of the engine.
I started to go the group 31 battery's route but decided to stay with the 8D's after talking to a few old bus mechanics who said
better stay with the 8D's in cold weather for starting.
Your choice!
jlv
I was fortunate with the people I was around when I did my electrical system! Most electrical on my bus was 24V. I cross tied the house system and bus system together with a selector switch, the same could be done with a solenoid.
If at any time the bus batteries were incapable of starting the bus, I could also tie in the house batteries with the flick of a switch. I used 2 group 31 ( group is only a size not an amperage rating) to start my 6V71. The house were 4 6V golf cart type batteries. I also had a block heater which could be used off shore power or generator. I used the block heater once.
I had no problem at all with 2 31's, but I spent my time in more temperate climates. JIm
I just left Advance Auto today and they have began carring the 4D&8D in their stores,4D 150.00 8D 179.00 I know this not real cheap but my thoughts are you need more than just starting power you need the storage cap.of the larger batt. for extended power when boondocking. Am I wrong?
What about using 4 (or 8 ) T105 trojans from your battery bank for starting.
A cheaper way to go would be to use 3-group 27 or even 24 batteries. You want to be around 2000cca. Or just use 2-31's and have a solenoid that can jump your house batteries if more juice is needed (I have that and it works great). Good Luck, TomC
Wiring 3- 12v G27's batteries is not a good setup for 24v IMO 2 need to be wired in series then 1 has to parallel could work ok for a while I guess never tried it,in my area small town AZ Interstate 8D's are 139.00 at Sams 179.00 for the 5 year warranty 8D's
good luck
8D's starting aren't that bad. Around here, they are about 160, with a five year warranty. Less might work, but you will probably end up swapping them out sooner.
Now, if you are talking deep cycle. Those babies are pricey.
Stick with the 8D's, if you can. Especially with a 8V92.
FWIW
John
Quote from: papatony on January 15, 2012, 08:02:17 PM
I just left Advance Auto today and they have began carring the 4D&8D in their stores,4D 150.00 8D 179.00 I know this not real cheap but my thoughts are you need more than just starting power you need the storage cap.of the larger batt. for extended power when boondocking. Am I wrong?
Starting batteries do not make good house batteries. For house use you want deep cycle batteries. Google deep cycle batteries and you will learn more than you ever wanted to know.
About 4-5 years ago my 8D's died and i replaced them with 2 group 31's. My 8v71 fires right off and i have had no problems. When it gets down below 40 degrees i use the block heater to help out. Once or twice it has been frosty out and i forgot to use the block heater and it took a second or two longer to fire off. The 31's are cheaper and a whole heck of a lot lighter than the 8D's. After getting my fingers caught between the 8D's and the battery box one time and thinking that i had either broken or cut off my fingers, i will never use them again......lots easier on my back too. :)
Quote from: jjrbus on January 16, 2012, 06:27:09 AM
Starting batteries do not make good house batteries. For house use you want deep cycle batteries. Google deep cycle batteries and you will learn more than you ever wanted to know.
That's true but unfortunately the term 'deep cycle' is thoroughly abused by battery manufacturers and retailers. True deep cycle batteries - the kind used in fork-lift trucks and industrial equipment - have really thick plates and are quite different in design to starting batteries. The thick plates also mean that the batteries will last for years and years, but they are expensive to make and don't give good 'numbers' (primarily because the surface area of the plates is limited). So such batteries aren't sold through high street retailers, where price and performance-on-paper is important. With some leisure batteries I suspect the 'deep cycle' bit doesn't go much beyond the label stuck on the outside.
Jeremy
For the record, this is my definition of a deep cycle. http://www.trojanbattery.com/Products/8D-AGM12V.aspx (http://www.trojanbattery.com/Products/8D-AGM12V.aspx)
Those are about $500 each. That is pricey. Flooded 8D's aren't that expensive in comparison.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.trojanbattery.com%2Fimages%2F8D-AGM.jpg&hash=0650f286b6d2a78acf4ab15de8d15f2c2815ba71)
I have found that the best place to buy batteries is from the wholesale place, mainly because i have to buy lots of equipment batteries. I think the group 31's are the best over all, mainly because of weight and the 8d types don't seem to last any longer anyway.
I like golf cart batteries for house batteries... although i recently found out they have cell tower batteries which weigh almost as much as an 8d, but it would take several to make up a house system.
The best price I have found for 8d batteries here is $170+ tax. Interstate was a bit over $200. Even Sam's was in the $190 area. It would be nice to find it cheaper. Clifford, will mentioning I know you get me a discount?
Thank you everyone for your comments. All this has prompted me to do a bit more research, as I think now that the size of the batteries is not what is important. What matters is the amperage the starter needs to turn the engine. So, I found this chart on the delco-ramey site regarding the 50MT starter:
http://www.newindo.com/delcoremy/images/delco%20remy%20starter%2050MT-24V_pc_sm.jpg (http://www.newindo.com/delcoremy/images/delco%20remy%20starter%2050MT-24V_pc_sm.jpg)
Based on this, if I can provide over 800 amps, I should be well into the power curve.
Chris.
Check out service bulletins from Delco 1B-216 and 1M-153 it explains the voltage and CCA for the Delco, the 8v92TA service manuals calls for 900 amps on a 24V 50MTstarter turbo 8v92 1150 for a N/A non turbo 8v92
I noticed I gave you the max CCA sorry about that
good luck
If your around any bus nuts have them ck out their local Oil/farm direct supply jobber. I pay far less for 31's than what people are saying here. Just bought last set. for $62 each Have had good service. The ones in the 89 are 5 yrs old and are strong as new. Name brand. Been getting 8 to 10 yrs with proper maintenance.
Chris -
The one thing nobody's mentioned yet is voltage drop.
If your starting batteries are still in the OEM location, you've got nearly a 40' run to the starter. Granted, it's a big cable, but voltage drop is something to consider.
Your MCI is also 24 volt, so that, too, has to be figured into the mix.
OTOH, the big 8Ds were spec'd for another reason not often mentioned: keeping the electrical supply somewhat consistent when operating the OEM HVAC system. If yours has been removed, then you've eliminated that heavy electrical load from the coach.
Many busnuts have gone to the smaller 31s with a tie-in to the house systems, a very common setup.
Perhaps Sean will pop in here and pontificate some on the finer points of this discussion. . .
FWIW & HTH. . .
;)
With my bus being 12v and all trucks in the U.S. being 12v, I forget that many of the buses are 24v. Of which, you'd have to use either 2 or 4 12v starting batteries. Two size 31's are enough. On my truck I have 4 size 31's with the truck running on 12v and the starter using 24v through a series/parallel solenoid. But-a big 14.6 liter 4 stroke is much harder to turn over then the 2 stroke. Good Luck, TomC
Yep size does make difference the 12L- 8v92 takes a little more to spin than a 9L- 8v71 both fire fast 1/2 turn not like the newer 4 stroke electronic engines
good luck
Quote from: CountingFireflies on January 15, 2012, 02:27:25 PM
Howdy -
I'm trying to be frugal with my new battey purchases, and the starter batteries have me perplexed. I have an 8v92TA, and I currently have 2x 8D 12V batteries with a Vanner system. Each battery spec's at 1380CCA. The 8D's are rediculously expensive. Given that my engine starts on the first revolution, can I get by with 2x 31 size cells with 800-900CCA? What's the minimum CCA to get that beast turned over?
Chris.
Continential 8D's aren't too expensive. If you add thermoil it is supposed to triple the life of the battery. I would be reluctant to under power your coach batteries, it just ain't worth it. It may still crank, but if you wile out the starter you will pay for it there 3 fold.
Just a follow up on this. I've been running with e size 31 starter batteries since this post, and they seem to be adequate. I've been in the southern climate, so nothing too cold yet. I can tell it's not got the oompff that the 8d's had. It doesnt have quite the snap when it turns over. Anyway, for those that were curious like me.... There you have it.
Cheers
Chris
RJ is the only one that pointed it out, the reason for the 8D's originally, was not for the starter but as a buffer for the huge draw of the over the road AC system. JIm 0311
That is not really the case on some buses the Eagle with the batteries mounted in the rear close to the engine used 3 group 31 for factory air 35 or 40 ft of battery cable back to the starter you have a drop in voltage no way around it.
Like Chris posted I used 2 group 31 in place of 2 -8D on a 4905 Sunday to start the engine it was no comparison with the 8D's I removed for charging maybe 4 would have better the 2 for 24v sucked
good luck
To add a little more info to my post, ( number 14) I have a 24v starter, no over the road AC, but do have the over the road heat and blowers....and my batteries as still up front in the original position. Lost prime a couple of years ago and it took awhile to get it going but the batteries did just fine for all of the cranking we did with it. Sorry Clifford, as soon as i touch the button she fires off. ;D
If works for you go for it Ed but we did a lot traveling in winter I'll stick with the 8D's you can never have to much batteries IMO if leave your flashers on for 5 hrs it will drain 2 group 31's lol they have no reserve compared to the 8 D's they die in a hurry.
Working on these thing trying to fire one sometime the 31's go in a hurry
I drove my 4104 with 671 for five years with two 31s with no problem, don't know how that will work with a 92 though.
I now have two 4Ds on my 4107 with 8V71 which work fine, sort of halfway in between. I used them instead of 31s mostly because I was in a bind on a trip and didn't have time to sort out all the cable changes necessary for 31s.
My father told me a long time ago you can never have too good of tires or too much battery. I'll stick with the 8Ds that it came with, no matter how much of a PITA they may be to handle.
If I plug in my cummins for about an hour, it'll start off one group 31. I run 2 - 31's, 12v system. My battery cables are about 2ft long 2/0, one for each battery.
Two(2) G31's have worked for me since 1997, but I must say that 8D's would have done a better job of cranking speed at cooler temps. In those conditions I preheat with the block heater or the Wabasto for about 45 mins. Preheating is nice on the engine.
Just forgot to mention - 8v71N - probably easier than some to start ::)
Just bought a new set(2)- last ones where bought in 2003 - I'm not mad ;D
Prevost has been sending them out the door with a set of 4 group 31's.
So, now there are 4 points of failure, instead of 2?
you pays your money, you takes your chances, no free lunch...
happy coaching!
buswarrior
Bob, you may be right but I can't lift those monsters anymore! Since I live in a mild climate it is no problem. You guys in the frozen wasteland have a totally different problem!!
My battery guy told me all the new trucks are using 31s.
Its not rocket surgery Gus - it all comes down to pounds of lead. If you have the same number of pounds of lead spread over more batteries we should both start the same. Personally if its cold enough that I have to spin it more than once I stop cranking and find some heat. And consider that I have failed miserably in my trip planning I might add. The only real drawback to smaller batteries I can see is more connections but it only takes one bad connection to shut the whole show down, no matter how many batteries you have.