Been a trying year so far. Just got boat in and went put for trial run. Had to adjust stuffing box, leaking like a sieve. Think it may be too tight, water coming out a little but it was gray to black color. Heard this may be packing material starting to burn. Can I just loosen or do I need to re-pack? Ran engine for a total of 2 hours before I noticed. Hopefully did not hurt shaft. Also ran through some tall weeds in shallow water. With a wing keel this puts quite a drag on boat. Twice while dredging through weeds black smoke came out of exhaust in water. I just throttled down, let it idle than proceeded. After got put of weeds it appeared to be alright. Any thoughts.