Clunk while 4.3 litre lx alpha one mercruiser is running

[Logan Montz]

I have a clunking sound coming from my engine and I'm not sure how to solve it so would anyone be able to help me find out what could be wrong?

 

[Bt Doctur]

Not much to go on .Start by shiffing into full fwd and remove the drive to isolate either engine or drive noise
clunking when starting or when running???
oil level clean and to the mark, oil pressure reading