mercury 60/40 rattle noise at idle

[Target]

I have a 60/40 jet that rattles at idle. When I given it gas the noise goes away but comes back when idling. You can hear it especially during the last 5 seconds of the video.

[youtube]https://youtu.be/ZJ5RAg4gttA[/youtube]

I have read that it could be the impeller hitting the intake liner because the impeller is loose. I tried to tighten the impeller nut and it seemed tight... do I really need to CRANK down on it? Is this sound a concern or is it normal?

 

[LarryMc]

Couldn't listen to the sound, I couldn't get your video to play.

Have you checked the nylon sleeve inside the impeller? If it is worn, it could cause the impeller to hit the liner. You don't need to "crank down" on the nut. I just make sure that the nut is fully up against the spacers and then bump it down a little more to line up the tabs on the tabbed washer with the flats on the nut.

 

[rotus623]

Yep I think Larry is on it. If he impeller is hitting the liner it will make a squealing sound. Take the impeller off and see if the noise goes away. If it does you need a new sleeve and to grease it up real good.

 

[richg99]

Smarter guys than I will no doubt pipe in....but. it seems to me that a rattling sound could also be preignition ( i.e knocking). I'd try some higher test gasoline and see what happens.

Or, wait for the motor-pros to post up before tearing anything apart.

richg99

 

[LarryMc]

Easy way to tell if the impeller is rubbing the liner is to paint the inside of the liner with black spray paint and run it for a few minutes. Then check the liner.

 

[RiverBottomOutdoors]

Easy way to tell if the impeller is rubbing the liner is to paint the inside of the liner with black spray paint and run it for a few minutes. Then check the liner.

Good tip. I'll have to remember that.

 

[Gulf flats Ken]

I have a new 2019 mercury 60 40 and it does the same thing from day one at idle and stops just above. I’m just past breaking in and still does it.

It is the impeller hitting the wear ring. I’ve loosened and centered the ring tightened with shims in place and still does it.

I even went as far as shimming down the wear ring for more clearance. Still does it.

I hope Mercury figures something out. The sound alone on a new motor is bad enough but knowing it’s literally wearing the wear ring at idle really bites.

This should be a recall or warranty covered. I hope to find out more from Mercury and get it resolved. If I do I’ll post.

 

[northern1981]

Anyone ever figure this out? My brand new 2020 does this also

 

[richg99]

this sounds like it may help answer the question.http://www.meanchicken.net/webmain/forum/viewtopic.php?f=109&t=20317

 

[handyandy]

have you checked to make sure all the bolts that hold the outboard jet housing to the midsection are tight? If one is loosens up it could back out enough and be hitting the top of the impeller. Had it happen to me even though it's relatively new you never know.