I would like some input if possible as I don't know what I need to do to address the following problem.
My Atomic 4 runs well but within a minute or two after putting it into gear (Forward) the decreases rpm and a noise can be heard (similar to a freezing shaft) following by a "bucking" sound and vibration. The engine stalls at that point. I checked the propeller shaft and it is free moving, so I don't blame the stuffing box. As the engine runs normal my guess is that the transmission is the most likely problem.
Your comments are appreciated. Thank you.
Lutz
Super Forum and I am blown away by your responses!!! Thank you.
Boat is located in Southern CA, Dana Point and regarding the engine I would say it is a 2:1 reduction gear (don't know for sure)..
I did go under water (boat is afloat) and the propeller and shaft are clean. Propeller engages in both forward and reverse. In neutral the shaft / propeller can be rotated "normal" (slight resistance - I assume from the stuffing box).
I will try to get a video/audio of the problem and will uncouple the transmission flange (Al's suggestion) to determine if the problem is unrelated to shaft & stuffing box. The noise is horrible but short lasting as the engine stalls within 5-10 seconds after the screaming begins. What worries me is the bucking vibration. I have not been in the engine compartment when it happens but would not be surprised if the atomic 4 "jumps onto my lap". This might be a video woth watching. By the way, ramping up the RPM to forgo stalling does not do a thing other than increase the bucking and screaming - not a good option.
My Atomic 4 runs well but within a minute or two after putting it into gear (Forward) the decreases rpm and a noise can be heard (similar to a freezing shaft) following by a "bucking" sound and vibration. The engine stalls at that point. I checked the propeller shaft and it is free moving, so I don't blame the stuffing box. As the engine runs normal my guess is that the transmission is the most likely problem.
Your comments are appreciated. Thank you.
Lutz
Super Forum and I am blown away by your responses!!! Thank you.
Boat is located in Southern CA, Dana Point and regarding the engine I would say it is a 2:1 reduction gear (don't know for sure)..
I did go under water (boat is afloat) and the propeller and shaft are clean. Propeller engages in both forward and reverse. In neutral the shaft / propeller can be rotated "normal" (slight resistance - I assume from the stuffing box).
I will try to get a video/audio of the problem and will uncouple the transmission flange (Al's suggestion) to determine if the problem is unrelated to shaft & stuffing box. The noise is horrible but short lasting as the engine stalls within 5-10 seconds after the screaming begins. What worries me is the bucking vibration. I have not been in the engine compartment when it happens but would not be surprised if the atomic 4 "jumps onto my lap". This might be a video woth watching. By the way, ramping up the RPM to forgo stalling does not do a thing other than increase the bucking and screaming - not a good option.
Comment