I have a '91 E350 7.3L IDI short school bus. I replaced the batteries about a year ago with two deep cycle starting batteries, and haven't had any problems until now. But now... I didn't start the bus for about six weeks, and unknown to me the extension cord I was running to my trickle charger wasn't working. I had a reading of 11.9 on the main battery, put it on the trickle for a while, and had no problem starting it. I drove it around for about 15 minutes, and all seemed well. Started again a couple days later with no issues, though it only read 11.9. But this time I only really moved it a few yards to get it out of some pictures my realtor was snapping.
Due to circumstances beyond my control I had to run my diesel heater quite a bit over the course of two days and I had moved the bus just far enough that I can't reach the 110V maintainer. The heater is currently wired into the starting battery, which I keep saying i'm going to change. I connected to a solar maintainer, one I've used with success in the past, and the charge mostly stayed at 11.9 while I was running the heater, popping back up to 12.3 when the heater was off. Today was the second day of running the diesel heater and I tried to keep my eye on it but all of a sudden it dipped to 10.5v. I turned off the heater and it immediately went back up to 11.7. I put the solar maintainer back on but lost sun shortly after that so I took out my trusty jump pack, rated for up to at 8.0 diesel. it has served me really well in the past. I It showed 13.9v going in to the battery, but it didn't work, and after 3 unsuccessful attempts it was down to 35% so I stopped trying. I'm charging it now but it's going very slowly.
Both batteries under the hood read 11.9v. When I first tried to start it sounded entirely dead (even though it read 11.7) and though it sounded more lively after being on the jump pack, it still isn't close to starting. Everything on the dash lights up bright, and gradually dims as the crank gets slower.
I'm wondering have Ijust not given these batteries enough driving around time to really bring them up? Or... never thought about the fact that the jump pack has a lithium ion battery in it, and I left it in the bus all winter, unused. I brought it in the house and charged it up about a week ago (it was at about 80% and I can't remember if that's because I had used it or if it lost that 20%), and it seemed to charge more slowly than usual, but it did eventually reach 100%. When I hooked it up the vehicle it dropped more rapidly I think than it has in the past. I kept trying till 30% and now it's inside getting charged, but it's really crawling.
Do I have dead batteries, or a dead charger, or both/neither? I don't have another vehicle to jump from.
Due to circumstances beyond my control I had to run my diesel heater quite a bit over the course of two days and I had moved the bus just far enough that I can't reach the 110V maintainer. The heater is currently wired into the starting battery, which I keep saying i'm going to change. I connected to a solar maintainer, one I've used with success in the past, and the charge mostly stayed at 11.9 while I was running the heater, popping back up to 12.3 when the heater was off. Today was the second day of running the diesel heater and I tried to keep my eye on it but all of a sudden it dipped to 10.5v. I turned off the heater and it immediately went back up to 11.7. I put the solar maintainer back on but lost sun shortly after that so I took out my trusty jump pack, rated for up to at 8.0 diesel. it has served me really well in the past. I It showed 13.9v going in to the battery, but it didn't work, and after 3 unsuccessful attempts it was down to 35% so I stopped trying. I'm charging it now but it's going very slowly.
Both batteries under the hood read 11.9v. When I first tried to start it sounded entirely dead (even though it read 11.7) and though it sounded more lively after being on the jump pack, it still isn't close to starting. Everything on the dash lights up bright, and gradually dims as the crank gets slower.
I'm wondering have Ijust not given these batteries enough driving around time to really bring them up? Or... never thought about the fact that the jump pack has a lithium ion battery in it, and I left it in the bus all winter, unused. I brought it in the house and charged it up about a week ago (it was at about 80% and I can't remember if that's because I had used it or if it lost that 20%), and it seemed to charge more slowly than usual, but it did eventually reach 100%. When I hooked it up the vehicle it dropped more rapidly I think than it has in the past. I kept trying till 30% and now it's inside getting charged, but it's really crawling.
Do I have dead batteries, or a dead charger, or both/neither? I don't have another vehicle to jump from.