Tranny Chatter

[Sadey]

Anybody experiencing this or have? Low RPMs on starboard motor, 690-1100, lots of chatter from the starboard transmission goes away after 1200 RPMs and runs smoothly. I’m going to have a pro check it out but wondered if anybody had a similar thing. Came up on the survey last year but has not been an issue to date. Seemed louder the other night but it was quiet out and didn’t have the radio so I’m not sure if it’s an increase in chatter or I’m was more aware. Headed from Racine Wi to Door County WI next week for a month long trip so I’m a little concerned.

[g36]

You have velvet drives? They re kind of known for it. Mine chatter a bit at very low rpms always have. The chatter goes away if i bump it up just a bit off idle though way before 1200 rpms . Nothing wrong with a check before a long trip. For peace of mind if nothing else. There's also some posts on here where its been discussed quite a bit . May try search

[tomschauer]

Most likely the damper (flex plate) has a bad spring or two.

[Cooler]

There are actually two very common sources for that chatter. You probably also notice it even more in reverse. The gears in the tranny are not machined for smooth operation on both sides, hence the reverse chatter. Pretty normal. Second your couplers could be getting worn out. Depending on the type and manufacturer, it may be getting to the point of needing replacement, but if they are smooth over 1000RPM, it is not likely to be something needing quick repair. Could wait till off season. Finally, check to make sure your fluid is full, but not over full, making adjustment for how your vessel is laying in the water. Good luck, see you in in DC! er

[Viper]

Source of the post Most likely the damper (flex plate) has a bad spring or two.

+1
Also consider that a cylinder misfire and runability issues can cause a transmission chatter too. Chatter at 1200 rpm seems a little excessive but I continue to see it all the time with seemingly no ill effects, however you can't tell until something fails or you dismantle to inspect whether the chatter is a sign of an impending failure or just normal for that particular unit. Keep an eye on the condition of the fluid. Sometimes an impact will rear it's ugly head through a transmission failure years after the running gear is repaired. For this reason, I always recommend transmission removal and dismantle after a good impact. Insurance companies don't like that as they prefer to minimize costs and just cross their fingers but it should be noted in writing that a future failure should be considered part of the original impact claim just in case that happens a couple of seasons later.