Idle speed rattle

[gkallevig]

So my 2016 190 fsh really rattles at idle rpm. the rattling stops once at just above idle, you can hear it quite down when put into jet wash mode. What's going on here? Something loose in the driveshaft?

 

[FSH 210 Sport]

So my 2016 190 fsh really rattles at idle rpm. the rattling stops once at just above idle, you can hear it quite down when put into jet wash mode. What's going on here? Something loose in the driveshaft?

Recently I saw a vid of a boater with this situation and it was a worn out intermediate bearing.

How many hours on your boat, and has the intermediate bearing been greased?

 

[gkallevig]

Recently I saw a vid of a boater with this situation and it was a worn out intermediate bearing.

How many hours on your boat, and has the intermediate bearing been greased?

160 hours. As i just bought it, i'm not sure about how often the bearing has been greased. I put in about 5 pumps the other night, but didn't seem to qquote down at all. I saw some grease coming out on the bottom of the bearing rubber, so it must be full? I can put another pump of grease in and see if its pushing out as I pump, or maybe that was a previous leak? The rattle definitely isn't the engine, its somewhere aft of that. I grabbed the prop shaft and couldn't feel any play in it.

 

[gkallevig]

Recently I saw a vid of a boater with this situation and it was a worn out intermediate bearing.

How many hours on your boat, and has the intermediate bearing been greased?

Hopefully that video link works.

 

[FSH 210 Sport]

Listening to the vid it sounds like an exhaust leak… has the boat made this noise since you bought it?

Reach down in there and see if you can feel any play in the prop shaft side of the coupling. You should probably pull the pump and you will get a better feel.

The grease is not supposed to come out of the rubber… it’s kind of a not so great design, it would be nice if there was a plug you could remove when adding grease so you could tell it was full.

 

[gkallevig]

Listening to the vid it sounds like an exhaust leak… has the boat made this noise since you bought it?

Reach down in there and see if you can feel any play in the prop shaft side of the coupling. You should probably pull the pump and you will get a better feel.

The grease is not supposed to come out of the rubber… it’s kind of a not so great design, it would be nice if there was a plug you could remove when adding grease so you could tell it was full.

I grabbed the prop shaft through the clean out port and didn't notice any play. Its made the noise since i bought it, which was 2 days ago. I doubt its the exhaust because the noise goes away at any rpm above idle. I don't smell excessive exhaust fumes either. For that bearing, if there's grease coming out the bottom, are the seals shot? I'll probably pull the pump housing and inspect the wear ring, see if there's any contact marks from the impeller.

 

[JDinfla]

Your impeller is hitting the stainless liner. I just upgraded mine last summer to the new type with delrin liner.

 

[anmut]

I have a slight rattle, very apparent when running it out of water. It happens when coming off of plane to for a few seconds. I don't worry about it.

 

[FSH 210 Sport]

I grabbed the prop shaft through the clean out port and didn't notice any play. Its made the noise since i bought it, which was 2 days ago. I doubt its the exhaust because the noise goes away at any rpm above idle. I don't smell excessive exhaust fumes either. For that bearing, if there's grease coming out the bottom, are the seals shot? I'll probably pull the pump housing and inspect the wear ring, see if there's any contact marks from the impeller.

I think @JDinfla is onto something.. I have seen other posts about the salt water getting in behind the wear ring and expanding causing the impeller to contact the wear ring. Have a good look up inside the pump with a strong light and if it is contacting the wear ring there will be a shiny spot.

@Leojay did a post a month or so ago with the same issue. https://jetboaters.net/threads/must-watch-the-ultimate-jet-pump-pull.31647/#post-514719

 

[jeffrt]

My 2012 (bought last summer, 190 hours) rattles too at idle speed. Once I put it into no wake speed, it smooths right out. Looking at the impeller, everything looks ok, so until it gets worse, I'm not too concerned about it.

 

[Dfred]

Second for @Leojay (and others) tips & pointers on the causes and solutions - very easy diagnostic and fix that may save you from hell and headache later
... ours just so happened to be rear bearing grease just needed love and attention: “smooth as butter” now. Very easy to pull the pump and run the engine... that will tell you right away if the rattle is the intermediate bearing inside, or at the impeller - housing/ring (high-spot issue mentioned) or with rear inner/outer bearings. When you pull the cones, inspect for water intrusion.... which could point to the problem and needs for more comprehensive repair work to the bearings).
Get supply of the gasket maker, thread lock for the bolts, and Yamaha Molybdenum grease (for use on the spline into the intermediate shaft), and a grease gun with marine/waterproof grease with injecting needle to get that fresh grease in as far into the outer/rear bearing and push out the old grease. (As best as possible step short of more involved pulling apart the shaft and bearings....). Freshen up the O-ring seal. While pumps off and your there, you may want to re-caulk the jetpump tunnel, grate joint/seam, etc. for smooth intake water flow, and tighten and seal the impeller shaft through-hull as @Leojay points out also (that leaks sometimes)

Photo of crappy rear bearing grease, and injecting new marine grease:

 

[gkallevig]

Second for @Leojay (and others) tips & pointers on the causes and solutions - very easy diagnostic and fix that may save you from hell and headache later
... ours just so happened to be rear bearing grease just needed love and attention: “smooth as butter” now. Very easy to pull the pump and run the engine... that will tell you right away if the rattle is the intermediate bearing inside, or at the impeller - housing/ring (high-spot issue mentioned) or with rear inner/outer bearings. When you pull the cones, inspect for water intrusion.... which could point to the problem and needs for more comprehensive repair work to the bearings).
Get supply of the gasket maker, thread lock for the bolts, and Yamaha Molybdenum grease (for use on the spline into the intermediate shaft), and a grease gun with marine/waterproof grease with injecting needle to get that fresh grease in as far into the outer/rear bearing and push out the old grease. (As best as possible step short of more involved pulling apart the shaft and bearings....). Freshen up the O-ring seal. While pumps off and your there, you may want to re-caulk the jetpump tunnel, grate joint/seam, etc. for smooth intake water flow, and tighten and seal the impeller shaft through-hull as @Leojay points out also (that leaks sometimes)

Photo of crappy rear bearing grease, and injecting new marine grease:View attachment 152141View attachment 152142

Well I pulled the pump assembly and ran the engine, and the noise wasn't there. So the noise must be aft of the carrier bearing. Aside from being very dirty and everything seized together,y pump assembly looked pretty good. I spun the impeller and didn't hear it hit the housing, nor did I hear bearing noise. I cleaned everything up, greased the rear bearing, and cleaned the wear ring (it had a lot of buildup, surprising for being a freshwater boat in the Midwest). I'll get it all back together tomorrow and hopefully things are quiet!

 

[FSH 210 Sport]

Well I pulled the pump assembly and ran the engine, and the noise wasn't there. So the noise must be aft of the carrier bearing. Aside from being very dirty and everything seized together,y pump assembly looked pretty good. I spun the impeller and didn't hear it hit the housing, nor did I hear bearing noise. I cleaned everything up, greased the rear bearing, and cleaned the wear ring (it had a lot of buildup, surprising for being a freshwater boat in the Midwest). I'll get it all back together tomorrow and hopefully things are quiet!

With that build up in the wear ring, sounds like it may have been wet slipped during boating season. Friendly reminder, grease the splined end of the shaft with molybdenum disulfide grease when reassembling.

Did you check the engine coupling for looseness?

 

[gkallevig]

With that build up in the wear ring, sounds like it may have been wet slipped during boating season. Friendly reminder, grease the splined end of the shaft with molybdenum disulfide grease when reassembling.

Did you check the engine coupling for looseness?

I did not check the coupling, didn't know that was a thing to check. Is that part of the mid bearing?

 

[FSH 210 Sport]

I did not check the coupling, didn't know that was a thing to check. Is that part of the mid bearing?

Yes. Its where the mid bearing shaft attaches to the crankshaft of the engine. There is a rubber dampener piece that goes between the two coupling pieces.

 

[randocommando]

Anybody know how much grease to pump in the zerk fitting? Is there a danger in putting too much?

 

[gkallevig]

Update: I put it all back together and running it in the driveway, it appears the noise is gone, or at least greatly reduced. I really didn't do anything other than re-grease the rear bearing and pack it 2/3 full, and clean up the buildup on the wear ring; between those two items i guess something did the trick. I checked the mid bearing and the coupler, both seemed fine.

Randocommand, there is a danger of over greasing, but there's no exact amount to put in. Yamaha says a couple pumps every year, and that's about as specific as they get.

 

[FSH 210 Sport]

Update: I put it all back together and running it in the driveway, it appears the noise is gone, or at least greatly reduced. I really didn't do anything other than re-grease the rear bearing and pack it 2/3 full, and clean up the buildup on the wear ring; between those two items i guess something did the trick. I checked the mid bearing and the coupler, both seemed fine.

Randocommand, there is a danger of over greasing, but there's no exact amount to put in. Yamaha says a couple pumps every year, and that's about as specific as they get.

Excellent! That is consistent with @Dfred post. Also great news on the coupler and mid bearing!

Hopefully all that is ahead for you now is many hours of enjoyment until winter!

I see that I did not answer your question about the intermediate bearing being shot due to grease coming out of it. While I have very little experience with it Id say you are okay as there is a video in the FAQ where a guy greases his until grease starts pushing out. When I did the 10 hour grease on mine, I measured out how much each pump of my grease gun puts out, then filled each bearing with the calculated amount of grease stated in the manual. This year I added a few pumps into each intermediate bearing while being cognizant of any increase in back pressure on the Gun handle while adding grease.

 

[gkallevig]

Excellent! That is consistent with @Dfred post. Also great news on the coupler and mid bearing!

Hopefully all that is ahead for you now is many hours of enjoyment until winter!

I see that I did not answer your question about the intermediate bearing being shot due to grease coming out of it. While I have very little experience with it Id say you are okay as there is a video in the FAQ where a guy greases his until grease starts pushing out. When I did the 10 hour grease on mine, I measured out how much each pump of my grease gun puts out, then filled each bearing with the calculated amount of grease stated in the manual. This year I added a few pumps into each intermediate bearing while being cognizant of any increase in back pressure on the Gun handle while adding grease.

Seems my quieted idle was short lived, I'm thinking it's back to about the same noise level now. It actually seems quieter when I start it out of water vs in. It's definitely rpm dependent though, still quiets with one click up on the no wake mode. I'm gonna check spark plugs shortly and see what they look like. Maybe re grease the mid bearing and see if the grease pushing out the bottom was in fact from me, or if it was there previously. Are exhaust leaks a thing on these boats?

 

[FSH 210 Sport]

Seems my quieted idle was short lived, I'm thinking it's back to about the same noise level now. It actually seems quieter when I start it out of water vs in. It's definitely rpm dependent though, still quiets with one click up on the no wake mode. I'm gonna check spark plugs shortly and see what they look like. Maybe re grease the mid bearing and see if the grease pushing out the bottom was in fact from me, or if it was there previously. Are exhaust leaks a thing on these boats?

I’ve never seen any reports of exhaust leaks on these boats, and you’d smell it in the engine bay if it were leaking in there.

Withe engine off and locked out, can you reach up into the intake and see how much play there is in the shaft ? You could get someone to help you so you can look at the coupler in the engine bay to see if there is any play there as well.

Does your engine run smooth? If it is missing or running rough at idle you could be hearing the lash between the impeller shaft and the short shaft that goes through the intermediate bearing. I know you checked it, but based on what I heard from your vid and what I’m trying to piece together in my head it sounds like the rubber dampener between the engine and the drive shaft that goes through the intermediate bearing is bad since it smooths out when you raise the idle.. speaking of idle, what rpm does the motor idle at?