Issues with Neutral

[afdouble]

Mates--

I'm looking for some advice. At low speeds my boat (not engine) makes a slight knocking sound while in neutral or low speeds. It is almost like a rattle, but I don't feel anything or hear anything at the throttle. It appears to be coming from the back of the boat, likely the nozzles/buckets/etc...

Additionally, the boat has always remained steady (in one place) when it starts and is in neutral. Recently, the boat tends to move forward ever so slightly (enough to notice and have a rider ask why I had throttle in forward).

I am wondering if the sound and movement are related. Has anyone else experienced this? My first inclination was to check the reverse bucket. While I have never had any experience with this issue, I have read that the reverse bucket can causes rattling/knocking. When I looked, with the throttle engaged in the first forward position, the reverse bucket clears the water outlet. I don't think this is the issue.

What am I missing? Thanks in advance.

 

[HangOutdoors]

I would definitely take a good look at the buckets to begin with. Make sure they are closing all the way and that they haven't been knocked loose.

 

[Julian]

Sounds like your reverse gate needs adjusting. The knocking sound could be the gate hanging too low and bouncing off the jet stream. This could also explain your forward creep.

Here is an FAQ on adjusting it:

https://jetboaters.net/faq/#faq-33

 

[afdouble]

Thanks, i will check the buckets again. But I wonder, isn't the chattering felt because the bucket is too low (and hitting the jet stream)? Conversely, isn't the forward creep because the bucket is too high (and letting more jet stream out)? It seems as if I have conflicting problems.

 

[Weeb]

My boat rattles a bit until it gets up to about 1400 rpm’s.

 

[Aqua Jetaway]

@afdouble and @Weeb - I realize that this is an old post, but I’ve been fighting the same issue for a while. I have a 2019 212X that I bought new in 2020. Im around 280hours at present. I’m wondering if either of your rattles got worse and you found the cause/solution to the issue?

 

[FSH 210 Sport]

Something else to check is excessive play in the love joy connection… the rubber cushion drives will wear out over time.

 

[FSH 210 Sport]

Just reach down in there and see if there is any play radially between the pump side of the love joy drive and the engine side… I know mine need replacing due to some play, and there is a bit of a rattle like noise I’m getting at idle. They’ll get changed out this winter.

 

[Aqua Jetaway]

I checked the lovejoy shaft and felt around as best I could. I didn’t feel any looseness or see any signs of rubber wear.

But…I did find that the bolts securing the IDS assembly to the bulkhead seemed to be loose. They easily rotated and I could move the washers around under a couple of the bolt heads. One of them tightened up from the bolt head side, but others need a partner to hold the nut on the back. Frankly, I’m surprised that even one would tighten without a wrench on the nut.

 

[Aqua Jetaway]

Well…Tightening the IDS assembly to bulkhead thru-bolts made a little improvement/change. This seems to have reduced the amplitude and the frequency a bit. I’m starting to lean towards the idea of a little slop between the impeller shaft and the lovejoy output shaft. I’m not sure that I want to chase this much further. I’ve read multiple complaints from others on the forum with the same issue from the same motor/drive. I’m kind of wondering if there’s a little more misalignment between engine and impeller shafts on the starboard side that’s driving a bit faster wear at the interface between lovejoy output and impeller shaft.

 

[FSH 210 Sport]

Well…Tightening the IDS assembly to bulkhead thru-bolts made a little improvement/change. This seems to have reduced the amplitude and the frequency a bit. I’m starting to lean towards the idea of a little slop between the impeller shaft and the lovejoy output shaft. I’m not sure that I want to chase this much further. I’ve read multiple complaints from others on the forum with the same issue from the same motor/drive. I’m kind of wondering if there’s a little more misalignment between engine and impeller shafts on the starboard side that’s driving a bit faster wear at the interface between lovejoy output and impeller shaft.

You’ve got this topic spread over several threads so it’s hard to keep track of.

How many hours are on this boat?
Have the intermediate bearings been greased ?
Have you pulled the pumps and checked the intermediate bearings for play without the pumps in?
From your responses it sounds like you need to make a better effort to check for play at the love joy connection to see if the rubber cush drive is worn out.
Have you pulled the cones on the back of the pumps and checked the grease and or water intrusion?

Do you have a shop manual? If not you need to get one.

Using a 1” wooden dowel or long screwdriver, and while the engine is running, place the dowel or screwdriver onto the intermediate bearing housing and then with your hand wrapped around the dowel, place the dowel up to your ear. This a mechanics stethoscope, and you can listen to the bearing, compare this to the other intermediate bearing as your problem seems to be asymmetrical.

 

[Aqua Jetaway]

Yes, I definitely have reached out on a few threads related to this issue. I’m sure that it’s difficult to follow where I’m at in the process. I should probably start a clean thread rather than hijacking other threads. But…

I have about 280 hours on both engines.
Both intermediate shafts have been greased.
I’ve pulled the pump with the noise and checked for play as well as run the engine without the impeller shaft installed - no play, no noise.
I’ve pulled the cone on the pump and inspected the cone bearing - all good, plenty of grease and no indication of water intrusion or bearing issues
I’ve inspected the impeller and housings for contact/wear - slight cavitation erosion on impeller with slight wear location on housing. I hand sanded housing and reinstalled with no change. This might be the issue, but the noise isn’t significant enough to warrant a new wear ring yet.
I’ve used a mechanic’s stethoscope to compare the sound at the bearing, but didn’t hear any appreciable difference.
I’m sure that a shop manual would be helpful.

Frankly, at this point I’m just going to keep monitoring the situation until it gets worse and is more easily diagnosed.

You mentioned that you have some rattle and need to change your lovejoy. I’m wondering how many hours are on your 2020 210FSH?

 

[FSH 210 Sport]

Yes, I definitely have reached out on a few threads related to this issue. I’m sure that it’s difficult to follow where I’m at in the process. I should probably start a clean thread rather than hijacking other threads. But…

I have about 280 hours on both engines.
Both intermediate shafts have been greased.
I’ve pulled the pump with the noise and checked for play as well as run the engine without the impeller shaft installed - no play, no noise.
I’ve pulled the cone on the pump and inspected the cone bearing - all good, plenty of grease and no indication of water intrusion or bearing issues
I’ve inspected the impeller and housings for contact/wear - slight cavitation erosion on impeller with slight wear location on housing. I hand sanded housing and reinstalled with no change. This might be the issue, but the noise isn’t significant enough to warrant a new wear ring yet.
I’ve used a mechanic’s stethoscope to compare the sound at the bearing, but didn’t hear any appreciable difference.
I’m sure that a shop manual would be helpful.

Frankly, at this point I’m just going to keep monitoring the situation until it gets worse and is more easily diagnosed.

You mentioned that you have some rattle and need to change your lovejoy. I’m wondering how many hours are on your 2020 210FSH?

735 hours on my 2020 210 FSH.

I got a set of these to put in this winter.



So, if you got no noise when the pump was out and you ran the engines, then the noise is associated with the intermediate shaft / impeller shaft interface and that slop due to the power pulses will make the impeller ring like a bell. Again, double check the play in the love joy coupler.