Bus Battery Replacement

[New2Skool]

Hello All,
Yesterday, I attempted to start the bus to fuel up.
It rumbled, rumbled and clicked.
The voltage was low, I checked the batteries.
The batteries were in the bus when I purchased and are 12 years old.
So, I replaced the batteries today and wired them into a 12v series.
They are 31 MHD batteries the same as original that ran the bus.
Jumped in the bus and all I heard was a click click.
The cluster powered up like normal, volts were in the green range.
Just didn't fire up.
I don't know what to do.

My bus is a 1998 International 3800, 65 passenger with a DT466 with 142,000 miles and was running like a charm previously.

I have two possible issues;
1. The batteries might be an issue.
2. I might be struggling for fuel given the low fuel level and angle of parking.

Thanks for any and all advise.
New2Skool

[opus]

Bad ground......

[roach711]

A bad connection would be my first guess also. Look for loose or corroded connections at the battery posts, the ground connections and the starter. Sometimes old battery cables get corroded inside the insulation. Look for puffy spots near the cable ends.

[Robin97396]

Getting 12 years out of a set of batteries is doing pretty good. I'd say those old batteries probably froze this past winter.

I noticed you didn't say you got "new" batteries. Is that why you think that could be a problem?

I agree with the other guys, bad connection. Probably the ground, assuming you cleaned all the battery terminals and connections while replacing the batteries.

[New2Skool]

Yes they are new batteries.
I will check the connections and especially the ground.
The terminals were surprisingly clean given the fact that the batteries were sitting in an inch of water when I pulled the tray out.
It was sprinkling all day yesterday but, the water surprised me.

Thank you gents for the help.
I will let you know how it turns out.

[New2Skool]

Hello Gents,
Once again, thanks for the input.
I had a coworker who is a former diesel mechanic check out the battery / starting issue.
After a good bit of investigating, we found that one of the black / ground wires was actually a red / positive line.
We checked the current at several points, traced the lines, connected and tested repeatedly.
Finally, once we were sure we connected the terminals and turned the key.
Now, it did not fire up immediately.
It has been about 10 days since it last ran and with the average temp being roughly 20 degrees it was not a surprise it didn't start.
I plugged in the block heater and returned later to try again.
On the third attempt it rattled, chugged and fired up.
I idled it for several minutes waiting for a friend to follow me to the mechanic.
It is now parked and awaiting its first full service under my ownership.
I am sure, I will need an oil change, filters of all types, hose leads tied off, and additional coolant given the amount removed with the cab heater removal.
We will see what else needs to be addressed and how much.
I am relieved it is up, running and at the garage waiting for a professional to check it over top to bottom.
Thanks for the help.