Hi everyone im' new to these forums. I have learned alot already by reading posts here. Well here is my problem. I just purchased a 1982 19' cobalt with a 57. merc. 260. The previous owner made his own custom exhaust out the side of the boat just above the water line. He said water could not get back to the engine even though he didnt' put any sort of check valve on the exhaust. Ok now to the problem. First it is very loud I thought ild' just buy a marine muffler for both and from everything I've read 4" dual exhaust is too big for 260hp. Second the boat starts great on the trailer with muffs, but as soon as i put it in the water it almost sounds like the battery is going dead (stranded me once) wouldnt' even crank. So i replaced both batteries. Took it out again and the same problem sounds dead on the water but cranks hard on the trailer. So does anyone have any ideas? Thanks in advance.
