Start Batteries Slow or fast

[chuckd]

Did not know a catchy title, looked through a lot of previous posts on changing from 8Ds for start batteries to group 31 or similar for that purpose.  Now I need new start batteries and 8Ds weigh as much as I do so breaking them up is a good thing.  Presently have two 8Ds for my 24 volt starter.  Now what I was wondering what is the "best" battery to start  my 6V92?  Does it like a high power burst or a slower burst from the deep cycle.  I start mine in very cold weather but normally have it plugged in.

So  what does my two stroke like?

Chuckd
Stillwater Mn
1979 Prevost

[Seangie]

Chuck - I've got (3) Group 31's in my Eagle 10 (6v92 Silver mechanical) and it starts right up without thinking.  I just had the starter rebuit which made all the difference from a laggy start to a quick jump.

I have not (nor plan to) live in cold weather.  I have seen someone post that they can start a 6-92 with (2) group 31's which might be a good fallback if one of your (3) batteries dies.  Keep you from getting stranded.  Much easier to carry around and cheaper to find/replace.

-Sean

[Lin]

We do not have an exceedingly cold winter.  I have stuck with the 2 8d's for years, but this year when I needed to change them, I decided I had had enough of fighting them and having to engineer a method of removing and replacing them.  I suppose if I had a forklift around, I may have kept them.  So, after listening to Ed H. boasting all the time about his trouble free alliance with group 31's, I decided to try that.  We installed 2 of them for 24v about three months ago and so far they work just fine.  My engine is not a great cold weather starter to begin with, so I use a block heater anyway.

[TomC]

Going with size 31's, you have to use either 2 or 4 batteries for 24v. Virtually every sleeper truck made has 4-31's. If you have the room-use 4. I use 2 to start my 8V-71-which cranks harder then the 6 since I have high compression pistons and do not have a problem. If I do, I can hit the switch on the dash and jump the 2-8D deep cycle batteries for help. Good Luck, TomC

[luvrbus]

I would go with 4 group 31 for a 24 volt system there may come a time when you are not able to plug in 2 group 31's can die in a hurry in cold weather cranking on a DD and the Delco 42 stater is not all that crazy about low voltage or low amps plus they are heavy suckers to change

You can never have to much battery it has happen to me driving at night the alternator belts broke 2 group 31 in my MCI put me on the side of in the middle of no where in about 1 hr in Nev after that it was 4-31's for me

A little insurance is cheap for the reserve you may or may not need CCA never meant much to me I like reserve fwiw 2- 4D batteries are better than 4 group 31's and not as heavy as the 8D's

good luck  

[Fredward]

Chuck
Living in the same climate as you but only using the bus in the warm half of the year, I have two yellow top AGM group 31s. They work ok starting the 871 down to about 65. Then they don't have enough reserve. (Me thinks me needs a new starter too). I was thinking of going with two 4DLT ($116.00 at Fleet Farm). Particularly with Clifford's comment about 4D. I make extensive use of the block heater and gotten by for six years this way.

In my rig the group 31 just doesn't leave any Margin for error.
Fred

[chuckd]

Thanks all.  I have a 22 X 20 platform, and I can fit 4 group 31s, with not much space left over.  Off to fleet farm tomorrow - if Fleet Farm doesn't have iy, you don't need it.

Chuckd
Stillwater MN, 80 degrees tomorrow.
1979 Prevost

[Boomer]

I'm with Mr. Clifford, more is better.  My preference is two 8D Caterpiller.  1550 CCA each, got them in both the Crown and Silverside.  I do have 3 group 31 Delco Remy's in the Eagle, it was factory with 31's.  Will see if they last longer than the Interstates which lasted exactly 7 yrs.

[gus]

If you can set it up you can always use house batts to boost starts in emergencies.

I have done it often with 12v, don't know if it would work with 24v?

[FolkBus]

Since I have lived, bussed, trucked and traveled in all the extremes of weather that the continental US can offer, I would not use anything other then 8Ds. To me the "bother" of checking water level in them twice a year is nothing compared to the peace of mind of knowing I will never have a problem getting started that is battery related.

--Mike   

[Oonrahnjay]

...  Now what I was wondering what is the "best" battery to start  my 6V92?  Does it like a high power burst or a slower burst from the deep cycle. 

      I can't think of any situation where a "deep cycle" battery would be a better battery for starting a vehicle than a "start battery".  You might have a condition where you have so many batteries and thus so much battery power from "deep cycle" that it works OK but they're not made for the big-bam needs that a start battery gets.  If you want to start, begin with the assumption that you're using start batteries; if you're running house batteries, assume that deep cycle will work best for you.  If you think you have conditions or a vehicle type that this wouldn't apply to, be *really* sure that you've got your facts right because it will be really rare.

      You talk about the slower burst - that's one of your issues.  A starter wants "all the power that it needs" NOW.  You don't want to be feeding a battery a lower amount of voltage, your starter will draw by wattage and it will try to pull more amperage that it can get.  One of the worst things in the world for a battery is to give them too little power.  In the car world, I used to tell people "a weak starter is the best way to kill a good battery and a weak battery is a best way to kill a good starter".    We put big loads on a battery and starter - you gotta have the right battery.

      (Sometimes, people with a big house bank of deep cycles will say "I'm hauling all these batteries around - why do I need start batteries".  Yeah, if you have big deep cycle capacity, you might get away with it and it will work in that case.  But if you're looking at two 8-D start batteries and you know that these will work fine, don't think of replacing them with two 8-D deep cycles.

[HB of CJ]

Used to be they were called high discharge rate or quick discharge rate or starting batteries?  I do not know if today there are different types of batteries that will do more than one job, or if that is even possible.   HB of CJ (old coot)  Old info may be....

A typical starting battery may be rated for a lot of amps over just a few seconds, or perhaps a minute.  Medium rate discharge batteries may be rated over about 1-3 days.  A slow or low discharge rate battery may be rated for a 30-90 day discharge rate.