Hi.
General checking at stops on a trip, some noise around the belt path developed. Next day after a 700 mile run in 12 hours, barely cranked and ended not cranking.

Jump started, measured voltage at idle : 14.30V. Turning off, after a while, voltage down to 10.50V. During starting attempt, about 8V. Low water in battery -boiled?-

I suspect one cell of the battery is bad.
Removed belt, spun alternator by hand, no noise. Spun idlers and tensioners, one was somewhat noisy.

Suspect after a long hi-rate charge, battery went kaput. Do you agree ?

Is your Disco putting over 14.0V charging at idle ?
Am afraid of toasting the new battery I will have to buy. Comments ?

 

14.4 is the top of the spec. Should be fine. Old battery had one or more dead cells.

BTW, if you want a cheap battery for testing and utility use, boneyards usually sell working pullouts for $25.

 

I agree the battery is the most likely problem.

Didn't know about the used battery tip - that's a good one.

 

When you buy a replacement make sure it has a 700 CCA rating or higher.

 

Thanks gentlemen.
From diagnostics and your confirmation; replaced battery, idle charging voltage is 14.21V; with air conditioner-on, 14.1V
Am confident that was the only problem. Ready for another 700 miles back NC outer banks to KY, praying for no surprises...

 

While at the OBX, the Wright Brothers Museum / Memorial is a neat stop. They have a small piece of the original wing fabric on a plaque. It is signed by some guys who took it along on a trip. To the moon and back.

Hope you have an uneventful trip back.