Keys Marty
Recruit
- Joined
- Nov 3, 2013
- Messages
- 3
Twin 2004 Suzuki 140hp 4-strokes on a 25-foot World Car dual-console catamaran.
When the boat is in idle or minimum forward or underway the motors are quiet, EXCEPT after about a half-hour under way, when I throttle back to stop, one or both motors, often, but not always, begins to screech. I just took a mechanic seven miles out to the reef to hear the noise, and it was very loud, but just from the starboard motor this time.
When I am in neutral or minimum forward it makes the noise, and the loudness varies dramatically each time, but as soon as I start to speed up, the noise disappears. Then, more often than not, when I throttle back to stop or idle the sound returns.
Today it was the starboard motor at the reef, but it was the port motor when I returned to the dock.
The mechanic called Suzuki in California, and it suggested the driveshaft bushings, but the mechanic had already changed them, and he thought the old ones looked pretty good. Suzuki then suggested the driveshafts themselves, but the mechanic had gone over them carefully, and he is convinced they are fine.
Two other mechanics suggested what one called an idler arm and the other referred to as a tensioner. I know nothing about motors, but they feel the 2004 motors might have timing belts, not timing chains, and the tension of these belts are controlled by an arm, that might not be functioning properly.
Someone, ntsuzuki, posted here on October 1, 2011, with the identical problem, but that post is closed, and I do not know how to contact him.
Help! What do you think?
When the boat is in idle or minimum forward or underway the motors are quiet, EXCEPT after about a half-hour under way, when I throttle back to stop, one or both motors, often, but not always, begins to screech. I just took a mechanic seven miles out to the reef to hear the noise, and it was very loud, but just from the starboard motor this time.
When I am in neutral or minimum forward it makes the noise, and the loudness varies dramatically each time, but as soon as I start to speed up, the noise disappears. Then, more often than not, when I throttle back to stop or idle the sound returns.
Today it was the starboard motor at the reef, but it was the port motor when I returned to the dock.
The mechanic called Suzuki in California, and it suggested the driveshaft bushings, but the mechanic had already changed them, and he thought the old ones looked pretty good. Suzuki then suggested the driveshafts themselves, but the mechanic had gone over them carefully, and he is convinced they are fine.
Two other mechanics suggested what one called an idler arm and the other referred to as a tensioner. I know nothing about motors, but they feel the 2004 motors might have timing belts, not timing chains, and the tension of these belts are controlled by an arm, that might not be functioning properly.
Someone, ntsuzuki, posted here on October 1, 2011, with the identical problem, but that post is closed, and I do not know how to contact him.
Help! What do you think?