Alternator tensioning arm keps breaking

[Harry Searay]

I've owned a Searay bowrider witha 3.0 liter mercruiser engine and have broken three Alternator tensioning arms in 9 years of owning the boat. Our local dealer said its not a common fault. Ive checked my belt tensioning and apart from this problem there is no problems with the motor. Any suggestions appreciated. many thanks , Harry , Lake Wanaka NZ.

 

[timguy]

Welcome. An abnormality in the pulley, usually the drive pulley on the crankshaft, can cause constant movement or pulses. This can cause bracket failure. Don't rule out a problem with ANY pulley. Check them all very carefully.