New boat from fresh water to salt

It is *IMPERATIVE* that you replace any fresh water Magnesium anodes with Zinc ones for salt water use.   Magnesium anodes dissolve far too quickly in salt water and will be gone before you realise what's happening.  Its *EMBARRASSING* when your prop drops off due to electrolysis.

If you cant haul out to do so within the week, then you need to get a hanging anode and attach its lead to the engine block. If there is an isolating coupling between the gearbox and the prop then add another one attached to the shaft.  This is only a temporary solution, till you can fit proper Zincs but keep the hanging anode(s) and always put one out when you are on your home mooring/berth as it will give you early warning if your anodes are being eroded too fast.  Don't forget to check your engine manual for any anodes in the cooling system that need to be swapped for Zinc one for salt water.   N.B. if going the other way, Zincs form an inactive crust if in fresh water for too long - short visits are OK.

There are various stainless brightening products.  Most of them are extremely toxic but do a good job if you follow the directions exactly.   Polishing will help, but you don't want anything too abrasive and on the lifelines it is important NOT to use anything that will leave abrasive particles in the core of the wire or that will trap dust and grit forming a grinding paste! :-(

No worries.  Magnesium anodes will last for a week or more in salt water.  Volvo Penta's recommendation is to change them if in salt water for over 7 days.  For a C026 on a mooring, you would get negligible electrolytic corrosion over couple of days or so even if the anode had dropped off unless the boat had a major pre-existing problem or totally unsuitable mixes of metals underwater

I just didn't want to risk your prop dropping off later this year if you did nothing . . . .

Unfortunately the anode should be well down the turn of the bilge and getting it above the surface will be VERY difficult.  Also, unless the previous owner was very particular about greasing the threads then applying a protective coating over the anode fastenings, then removal may well involve grinding the studs off and knocking them, through from the inside. I wouldn't want to do *that* afloat.   

If you were organised, with all tools, the parts for the job and  spare studs, backing blocks and sealant all on hand, you could do the job dried out between tides, either along side a quay or careened on a sheltered sand, gravel or firm mud beach.

However the haulout is worth it as the antifouling is fairly likely to be also unsuitable for salt water (ineffective, not too quick dissolving like the anode). If so, or if you cant find out what has been used, a coat or two of a normal marine antifouling over the top would be well worth doing