Help! What kind of batteries do I need for my bus?
I am the proud owner of a '91 International with a DT466 engine. I purchased the bus recently post interior conversion and my friend converted it to run off of SVO. Sadly, like a fool, I did not disconnect my batteries before letting the bus sit for a long time in storage. Now as spring time blossoms, I find myself unable to start my bus because it appears the batteries are dead.
The bus came with two batteries which I believe are wired in parallel. The first battery was unlabeled (does not list CCA) but was relatively small, it looks like your standard old truck starter battery. The second battery is an extremely large battery (looks like an 8D in size). Again, the labeling is not very informative. However, it does rate the cold cranking amps at 1150.
I purchased a marine/deep cycle automatic charger, pulled the batteries, and let them charge up till the charger indicated green. The small battery will not hold a charge, at most my battery tester reads weak at worst it reads bad. My charger spent a large time in 'desulfation cycle' for this smaller battery. The 8D battery at best reads good but quickly discharged (while not connected) to weak and may further discharge till the tester reads bad (waiting to see).
I am looking to replace these batteries this weekend with some group 31 and/or 8D replacements. However, I have no idea how to determine how many CCA I need to get the International started. Should I use 2 group 31's in parallel? Do using an 8D even make sense at all for starting?
Please help! I am a novice in all things mechanical and very lost at this point. Thanks!