Hi, Sorry for my ignorance on this one but i have just bought a Trophy 21 ft wa with a merc 150 v6. The engine is starting first time and i had the boat on a trial run last week. The engine was a replacement which a got a dealer to add a few months ago as the previous owner of the boat had blown a piston on the merc 175 which originally came with the boat. The problem i have is that the temperature gauge on the dash is not working, there is a slight jerk of the needle when ignition is switched on, but no further movement when engine is running (for 5 minutes in a barrel at idle). I did re-attach a tan coloured wire running down the right hand side of the engine block, which had been removed or come loose from a connection. Any ideas as to what i can do now. Thanks