Small Engines (Lawn Mowers, etc.): Is starter bad, cranks, volts

Question
Craftsman riding mower, LT3000 with B&S engine 31P977,  4 years old
suddenly won't start.  Symptoms: turn key and get first crank sound then nothing.  Battery is 9 months old and charge above 12.5 volts.  I can remove plug and engine will turn over good.  I jumped positive voltage directly to starter and again 1 to 2 cranks then nothing, same as with key. For fun I jumped it with another riding mower (bigger) (bat to battery)and I got it to crank and it ran good.  Ran it for a minute and it barely cranked with its own power.  I am just about to order a starter but want to be sure. It almost seems like starter quits when on load, that is engine under compression.  Had no trouble until  the winter
This effort tried on a mild day.

richard

Answer
Richard
Just because the battery reads 12.5 volts doesn't mean that it is good,it may not be able to handle the amps that the starter requires.If it cranked with a different battery then the starter is not the problem. Take the battery to a place that can test the battery to see if it can hold a good charge.