As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A NEW LIGHT WEIGHT STARTER WAS INSTALLED WHEN THE EXISTING STARTER FAILED. THE STARTER CONTACTOR WELDS ITSELF TOGETHER AFTER ABOUT 15 STARTS. 2 NEW MFG CONTACTORS WERE INSTALLED AND HAD THE SAME RESULTS. A HEAVY DUTY CONTACTOR HAS BEEN INSTALLED IAW MFG SERVICE BULLETIN. THE SUSPICION IS THAT THE NEWER STARTERS DRAW SO MUCH MORE IN RUSH AMPERAGE WITH THE LARGER ENGINES CAUSING THE CONTACT TO WELD AND STICK.