Damaged drain bolt

[Bluebc]

Hi, just purchased a 2004 boat had water leaking from the drain bolt in lower block on left side.

Last owner definitely had issues with it as it was gasket sealed up only started leaking when engine got up to temperature.

I removed Brass bolt, treads are stripped from the blot, also purchased new brass replacements unfortunately it won’t go in the tread in block itself looks eroded and not much tread to be seen. Any tips on direction to go?? 

[Bozboat]

If I understand your situation correctly, You need to use a Tap and cut or clean the threads in the block and then install the new brass plug.

see this thread for help. The knock sensor is on the opposite  side of the block drain plug, but the threads should be the same.

 

Edited May 8 by Bozboat