| Author | Message | ||
| Nellie Wilson (Vivianellie)
Registered Member Username: Vivianellie Post Number: 451 Registered: 11-2008 Posted From: 66.87.0.24  Rating: N/A |
I knooow… but I warned you, right? Too orient everyone, mine’s an MCI 5C (though I’m beginning to suspect there’s not a pinch of difference between buses). I’m using the Big D8s (matching Exides, if that matters). The top battery suddenly went AWOL. Worked great and just quit, without warning. It still holds 12v but drops to zip on the load tester. Trouble shooting efforts: Disconnected batts and recharged both with ‘smart charger’ and voltage was good. Reconnected, tried to start, and nada. Load tester still agreed… nada! Hooked up a smaller – group 29 or 27 (or something) – and bus fired right up. I let bus run and checked charging rate. The top battery (the replacement) took a charge immediately and, after about 20 minutes, the bottom batt started charging too. Shut her down, kicked her again and she started in half a crank. So I’m convinced it’s a bad upper battery. But I’m sure open to contrary opinions? Assuming it is a bad battery, I prefer to get something smaller (read: cheaper) than another 8D (third one gone bad). Is there any problem using different size batteries? My thinking: Buy two smaller bats and hook them in parallel to replace the top 8D. Then – if the bottom 8D takes a dump – I can replace with one of the smaller (top) batts and still have 24 volts. For that matter, if one of the small batteries quits I still have 24 volts. Just thinking ‘redundancy’ here… and, as you might have guessed, I don’t have much faith in 8Ds. Re: 8Ds: I needed them up north (check the weather) but not down here. And traveling north of the Mason-Dixon Line is not one of my higher priorities. Several BusNuts that I’ve met, including my dear friend Ralph Peters, have moved away from the big 8Ds… and some of them live in (fairly) cold climes. So whatta ya think? Thanks for the ear… Nellie | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 399 Registered: 3-2006 Posted From: 216.198.139.38  Rating: |
Nellie I have run group 31's for awhile now and no problem. I don't run in the winter but still have started it in fairly cold weather with no problem. You should not mix battery sizes or different age groups if you want the most service out of them. The one that has gone bad on you probably has an intermitten connection internally. One of the bars that join the different cells together is likely broken. Bill | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1950 Registered: 12-2000 Posted From: 174.91.146.94  Rating: |
Are you tapping 12 volts off of this battery set? That's a recipe for killing one of them. happy coaching! buswarrior | ||
| ED Hackenbruch (Shadowman)
Registered Member Username: Shadowman Post Number: 341 Registered: 11-2003 Posted From: 75.211.73.35 Rating: N/A |
How old are the 8D's? When one of mine died i got rid of both and went to 2 group 31's. Have worked fine for 3 years or more now in my 5A with an 8V71. If i am in cold weather, (which i try to avoid like the plague) :>), i turn on the block heater for a couple of hours before i am going to leave. She fires off as soon as i hit the switch. | ||
| Nellie Wilson (Vivianellie)
Registered Member Username: Vivianellie Post Number: 452 Registered: 11-2008 Posted From: 66.87.2.123 Rating: N/A |
Thanks guys… So, Bill, if that’s the case (internal bar broken) the batt is definitely shot? What I can’t figure is how it happened? It started and ran fine and I haven’t used the batts since parking here (several weeks). BW: No 12v tap - just use the batts for starting. Ed: Tag on batts says ‘Shipped April ’06’ (never noticed that before). I purchased in January of ’07 (or maybe ’08? I’ll have to check). Isn’t that a pretty short life? Anyway, hate to toss the good one as it checks out fine. Figured two smaller ones paralleled would make a close balance. Plus provide the redundancy I mentioned. One other thing: I’ve got a Vanner equalizer that’s unhooked. My once-upon-a-time mechanic pulled the cables, said it was hooked up wrong. Never got back to that, but been driving it since (two years) without problem. Maybe that equalizer is my next project… but that’s another subject (I think). Thanks again. Any further thoughts much appreciated. Nellie | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1390 Registered: 10-2006 Posted From: 69.19.14.34  Rating: N/A |
Smaller , lighter batts will work, BUT you may loose the ability to start in the cold. A good block heater , or heading to Panama is a choice. FF | ||
| Bruce Henderson (Oonrahnjay)
Registered Member Username: Oonrahnjay Post Number: 642 Registered: 8-2004 Posted From: 70.60.102.56  Rating: |
"Ed: Tag on batts says ‘Shipped April ’06’ (never noticed that before). I purchased in January of ’07 (or maybe ’08? I’ll have to check). Isn’t that a pretty short life?" That may be a big part of the problem. Another issue could be "sulfation" or loss of the "charging paste" from the plates. If those batteries sat in a warehouse for months without being charged, there's a good chance that they ran themselved down to a discharged condition. When that happens, the paste on the plate will disconnect and precipitate down to the bottom of the cells in the batteries. When this "slush" of paste reaches the bottoms of the plates, it shorts them and the battery is at that point worthless. FF often says that the worst thing for a battery is for it to fall down below half charge (either by having too much juice pulled out of it, or by just sitting unused) and he's really right about that. Whatever, if it reads good on the voltage (which is a really bad way to try to check on a battery anyway) but bad on the load tester, it's toast. I can sympathize, I'm off to the NAPA here that stocks "heavy-duty" stuff for two 31's myself in a few minutes. | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 400 Registered: 3-2006 Posted From: 216.198.139.38 Rating: N/A |
Nellie Generally a 5 year life span is about all we get out of batteries. Some will last longer but because we let them sit most of the time it shortens their life. You might want to have the one checked by a reputable battery place that isn't just out to sell you new ones. Maybe Shawn or George can help out with a better explanation then I did. Bill | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 401 Registered: 3-2006 Posted From: 216.198.139.38 Rating: N/A |
Sean Sorry I spelt your name wrong. You know who I meant. Bill | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 193 Registered: 1-2010 Posted From: 68.151.225.213  Rating: N/A |
Hey Nellie Just went through a run with my Vanners, I now own 3 of them, If your coach is running 12 volt head lights etc you are tapping 12 volts off the top battery. My old MC5A used 24 volt exterior lights and so didn't have the equalizer but since yours has a vanner it just might have been converted to 12 volt and as previously stated pulling 12 volts off the top battery without the vanner or other equalizer is death to the battery. I have the service, test and trouble shooting book for Vanner. It has all the models in it excluding the very newest units. If you are using 12 volts then best to get the vanner working. If you need the book I can send it to you in PDF format Les | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 1152 Registered: 8-2006 Posted From: 99.68.214.35 Rating: N/A |
We do remember from a post a year or so ago about headlight troubles, that the bus has had the headlights modified from the original design. So Nellie, please look at the cable connecting the positive terminal of the grounded battery to the negative terminal of the other battery. If there is a small wire connected to either end of that large jumper, 12 V is being "robbed," and is the probable cause of the battery failure. You also can buy two smaller batteries each rated half of the good 8D, and parallel them in series with the 8D, which will work well. From personal experience, two group 27s will start a 12V71 just fine. Welcome back, G | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 2012 Registered: 10-2003 Posted From: 71.58.71.157  Rating: N/A |
You ARE adding water to the cells as necessary? Try another brand? How far down do you draw them? | ||
| larry currier (Larryc)
Registered Member Username: Larryc Post Number: 341 Registered: 2-2007 Posted From: 207.200.116.13 Rating: |
Some may have a way to use mixed batterys but I don't. If you run and charge all day, the alternator will boil the water out of the smallest battery and smoke it. | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1343 Registered: 5-2001 Posted From: 65.74.72.213 Rating: N/A |
Larry, it's not the smallest battery, it's the battery with the lowest voltage chemistry. That's one reason sulfation hurts batteries; the specific gravity stays low and the voltage does, too. If the voltage regulator is set low enough, the charging system won't boil any batteries. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1344 Registered: 5-2001 Posted From: 65.74.72.213 Rating: N/A |
double posted Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska (Message edited by pvcces on December 08, 2010) | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 1154 Registered: 8-2006 Posted From: 99.68.214.35 Rating: N/A |
I would like to politely disagree with both of the above posts, for the following reasons. 1. Amp-hours are amp-hours, whether they all go through one big battery, or half of the total each go through two small batteries. Granted, if you series ONE small battery with ONE large battery, and apply charging voltage, you will boil the small one. But, if you parallel two small batteries, each rated half the Amp-hour rating of a large battery in series with them, it will work fine. Please remember that each cell in all of our batteries is a whole bunch of plates in parallel, and a 12 Volt battery is 6 cells in series! 2. Lowering the charging voltage to where a small battery in series with a large battery won't boil when fully charged, won't charge the large one anywhere near fully. Although I would NEVER recommend connecting two different sized batteries in series, think about this for a couple of minutes... A 100 Amp-hour batt is in series with a 200 A/H. We start out with both fully charged, and draw 50 A/H out of them. The 100 A/H is half discharged, and the 200 is 1/4 discharged. Half of a hundred is fifty, as is a fourth of two hundred. So, the two can be recharged in series with no damage. This doesn't work if the two batteries weren't EQUALLY charged to start with, which is exactly what happens when stealing 12 V from a 24 V system. G | ||
| Nellie Wilson (Vivianellie)
Registered Member Username: Vivianellie Post Number: 455 Registered: 11-2008 Posted From: 66.87.4.179 Rating: N/A |
Wow. This discussion is getting confusing. And to think, it's all about an ancient and non-moving technology, i.e.: mundane old batteries. Imagine were it about some electronic hi-tech computer driven thinga-ma-jig.  Kidding aside, I'm taking it all in and am grateful to all. Bruce: I think you're at least partly right... it sat too long before I bought it. Bill: Good advice but, in my limited experience, a "reputable battery place" is an oxymoron. Nothing against battery joints, but never walked into one that knew (or cared) dic*. Frankly, I'd rather rely on my own tests... and the opinions on this Board. Les: I think you're partly right too. And I would LOVE to receive your Vanner info. BTW, what do you mean by "just went through a run" with your Vanners? George: Your memory is spot on. I will check for that wire. And thanks for your thought on smaller (paralleled) batteries. Chessie: 1) I check and fill (if needed) every few months (use distilled water only). 2) I will NEVER buy Exides again. 3) I confess to dragging the top one down (unknowingly) a couple times, but not deeply down. And I never let it sit in a discharged state. Larry: And just when I think I'm on track, I get to you . Please expound. BTW, I got a very pertinent e-mail from a fellow. I think it would be of interest to all, and he's given me permission to share it. But this post is already too long... I'll move ahead with that tomorrow. Right now I need some zzzzzzzzzzs. Thanks guys! Nellie | ||
| ED Hackenbruch (Shadowman)
Registered Member Username: Shadowman Post Number: 342 Registered: 11-2003 Posted From: 75.211.54.131 Rating: N/A |
Nellie, since you are in a warmer climate now you might want to check your water level more often and keep the batteries topped off. Try it on a monthly basis or even every two weeks if needed. | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 197 Registered: 1-2010 Posted From: 68.151.225.213 Rating: N/A |
Nellie I sent the info on the battery equalizers to your e-mail that is listed on your profile. My issue with them was my own fault. I didn't know that it is critical to disconnect the ground first when disconnecting the unit and to connect the ground last when connecting it again... very important! OOPS Have you determined if you have a center tap on your batteries? Les | ||
| Jack Fids (Jack_fids)
Registered Member Username: Jack_fids Post Number: 284 Registered: 1-2009 Posted From: 69.171.161.154  Rating: N/A |
Excide.... I think that was the name on the bottle of cheap wine we used to drink when we were a lot younger... at least it tasted like it came from them.... |
