I have a 4.3L that will not turn over easily. I was out on the water and had just previously replaced the throttle wire and had the idle wired too high, so the engine was idling around 3500 rpm. I shut the engine off when it was idling high and when I attempted to crank it over again, the starter was having trouble cranking the engine. Eventually the bendex spring in the starter broke. I took the started to the local auto shop and the starter was bad. I replaced the starter, coil & starter solenoid 2 weeks later(the boat sat with salt water during this time). Now the engine will not crank more than 1 rotation at a time when I turn the key and it is struggling to do that. The starter is engaging and the motor is turning slightly, so I dont think the engine is seized?? Is is possible for the something else to be seized up preventing easy rotation of the engine. Hydrolock maybe? The battery is brand new, and all of the connections are clean. Could this brand new starter be bad, or are my problems much greater???