Banging noise when trying to start boat

[ropiss]

There is a banging noise when I try to start my boats engine. Sounds fine for first second then clunking/banging noise starts. At this point I stop trying to start it Had a sharp wining sound when I started it yesterday but sound whent away after the first minute or so. Engine is a i/o merc v-8 alpha one. Any suggestions

 

[rodbolt]

Re: Banging noise when trying to start boat

Hello<br /> pull the drive to isolate motor or drive banging. could be the starter failing could be the coupler failing. if the motor bangs with the drive off take the plugs out and retest with the safty stop lanyard pulled or the ignition grounded. if no banging put the plugs in one at a time until it bangs then start testing that cylinder<br /> good luck and keep posting

 

[SS MAYFLOAT]

Re: Banging noise when trying to start boat

Sounds like the bendix on your starter has failed. Suspect that the bendix stayed engaged on the flywheel, that was the whinning sound the day before. Now when you try to start, the bendix is just bouncing around against your flywheel.<br /><br />Remove the starter, and bench run it. The starter drive gear should slam out to the end of its shaft. If it doesn't, you will need a new bendix or just replace the starter. JMIHO....SS