Is there any detergent to clean corrosion or I have to scrab it off with a knife, sand it; and anything to prevent it inside the motor and the holes for the bolts of the lower unit, threads are O.K.
I will. I will boat in sweet waters - in the Danube river I just can't wait for the time to come, meanwhile I intend to check up the thermostats.
I will remove them and see if they will open in hot water. scrub clean and if o.k. I'll put them back.
