I have an all original 1982 50 HP merc. The compressions are all in the 135 range. The idle is good, acceleration seems average, but much less than it used to be. Every year the last three years it's been getting weaker. Now it can barely plane off if I put two people in the boat, and has a max rpm of only 4,000 at about 22 mph. If it's just me in the boat it will do 35 mph at 5200 rpm. I tried a smaller lower pitch prop (original one from 1982) and got even worse even though it's only a 10.5 x13. The 10x15 stainless one actually gives more rpm and speed.
I'm wondering if bad reed valves will cause a lack in top end power or if it only would cause low rpm problems. Also, where are the reeds located. In my jet ski's they were bolted to the intake just directly below each carburetor.
Besides reeds, what other things can cause low power on this engine? Timing is set right, carbs seem fine and the plugs all look even and clean. They're light brown, not running lean or rich.
I'm wondering if bad reed valves will cause a lack in top end power or if it only would cause low rpm problems. Also, where are the reeds located. In my jet ski's they were bolted to the intake just directly below each carburetor.
Besides reeds, what other things can cause low power on this engine? Timing is set right, carbs seem fine and the plugs all look even and clean. They're light brown, not running lean or rich.
