Grinding gears behind instrument panel?

[Billtex2000]

OK, so I noticed a slight gear noise coming from behind my instrument panel today. Was hard to hear over the engines but it was definitely there. Sounded like small gears meshing/whirring. I've suspected that my port tach is off for some time now. It lags behind the starboard by about 600 rpm. I know they're electronic, but are there gears inside that might be crapping out? The speedo maybe? Any thoughts?

 

[MIDLIFECRISIS]

No gears on the tach or the speedo. you are probably hearing the steering cables.

 

[Gym]

@Billtex2000 try isolating the trouble a little more. Run one engine while the other is off to see if is coming from a tach. If on the trailer your speedo will be out of the equasion. Do you hear it only while you are turning the wheel or is it constant? Is it possible it is a vibration that may sound like gears grinding when the engines are running? Does your speedo work properly or does it jump around? You can also take the 5 screws out of the instrument panel, roll the panel towards the steering wheel to access the back. You can then unplug or swap the connectors to the tach if you think that may be the cause.

 

[Murf'n'surf]

Probably a vibration if you don't hear it while the motors are off.

 

[Glassman]

There's got to be a way to test the instruments with the engines off. You've got me curious, so I'll see what I can dig up.

I hope it's as easy to fix as the time I had a noise coming from MY helm...I finally figured that one out. It was a loose nut behind the wheel!

So my wife took over and it was resolved.

 

[Cobra Jet Steering LLC]

sound travels, I would check to see if a bilge pump is running and telegraphing the sound

 

[Glassman]

sound travels, I would check to see if a bilge pump is running and telegraphing the sound

I doubt it Jeff, but anything's possible.
On Saturday I was floating with the engine compartment open while changing my spark plugs and the bilge pump was on and on the occasional whirr from the pump was barely audible. Once I closed the hatch it was inaudible. If he can hear anything at all at the helm with the engines running, it has to louder than the bilge pump.

 

[Cobra Jet Steering LLC]

yea I know wild ass guess, but what on earth could it be, I have heard electronic relays make a vibration but not a grinding sound so I have no idea what could do that behind the dash.

 

[MNdrifter]

I keep my slide anchor under the starboard bow seat. If it slid back into the helm and was vibrating against something it might sound bad.

 

[MrMoose]

My new AR240 had the same symptom pop up after my 1200 mile tow from Ft. Lauderdale. I noticed an increase in the grinding/vibration sound coming from the dash as I increased the rpm on my port throttle. Increasing the rpm on my starboard throttle lever did not affect the symptom. I also noticed that from time to time as I transition my port throttle from idle to wake to cruise I'll feel a vibration come up through the port throttle lever. Last time I pulled the boat out, I quickly checked the buckets for any kind of play, but they equally seemed solid when the shift lever was in neutral. Next, I'll see if enough play develops in the port bucket to generate some type of vibration due to the jet hitting it, as I move the throttle lever forward from neutral to cruise. Although the noise sounded just like a noisy tachometer that I used to have on my old VW Scirocco, and the noise really sounds like it's coming from the port tach, I want to make sure that the bucket/throttle linkage is solid first. My port throttle lever also suffers from pullback, so maybe things just need to be recalibrated and snugged up. One thing is for sure, I'm not taking it to the dealership that I bought it from to have their ex-Sea-Doo mechanic learn on my boat. He's already demonstrated that he does not follow the instructions on the shop order, and he has also demonstrated that he is capable of "fixing" a problem so that it ends up worse than when he got it. Yup, still a little bitter from the experience.

 

[Gym]

I wonder if it's an impeller cone bearing transmitting though the hull. That is fairly easy to check while on the trailer. Just run one engine at a time and listen to each. You could also pull the pump to visually inspect them.

 

[Glassman]

@MrMoose , you might be on to something there....the throttles or the steering cables could be transmitting a vibration to the helm. @Billtex2000 , you might want to take a look around the jet pumps to make sure everything is nice and tight and the way it should be.

 

[Billtex2000]

Not the bilge pump or something rattling. Don't hear is with the motors off but then the tachs are not working either. I've been trying to think of what to compare the noise to and the closest I can think of is the sound one of those small wind-up toys makes when it's running. Like a fine set of friction gears winding. @MrMoose my port throttle drops a little too and hits its stop about 1/8"-1/4" before the starboard. No vibration though. Plus, as I think I mentioned, my port engine rpms drop slowly from about 5000 on, ultimately settling about 500-600 rpms lower than the starboard at WOT (7600 port vs. 8200 starboard) with the throttle lever together that is. Now, whether my port engine is dropping off at high rpm, my port tach is funky, my cables/throttles need adjustment all remains to be seen. Bottom line is, the boat is going into the shop in spring for a good going over. My fuel gauge finally crapped out, so that needs to be addressed as well. I'll have them do all of the adjustments, plugs, oil changes, lubrication, and fix the fuel sender. One thing I will do next week is swap the tach wires and see what happens. That's a great idea @Gym.

 

[Gym]

@Billtex2000 The throttle drop is a common issue with our year boats. You may be able to resolve it by tightening the friction screws under the rubber cover on the back of the throttle quadrant but usually that has little effect. @Speedling came up with a fix that you can find in @Julian reference thread Check Here For Your Answer First which is near the top of the General Discussion forum. Many people have applied his fix with great results.

 

[Julian]

Could it be something as simple as the vibration noise from your reverse gate being a little low?

 

[Matt Phillips]

I noticed about two years ago that when turning the steering wheel I'd heat a gravelly sound. I got some spray lube and put it on the pivot bolt for the steering, as well as the ends of the steering cables...turn the wheel from side to side and work the lube in. This seems to keep lube on the steering cables and bearings behind the dash and helps a lot.

I don't think this is listed as a lube point in the manual -- or is if it is't one of those every 100 hrs kinda thing. I do it a couple times per year and the steering is much easier.

 

[MrMoose]

Not the bilge pump or something rattling. Don't hear is with the motors off but then the tachs are not working either. I've been trying to think of what to compare the noise to and the closest I can think of is the sound one of those small wind-up toysView attachment 27621 makes when it's running. Like a fine set of friction gears winding. @MrMoose my port throttle drops a little too and hits its stop about 1/8"-1/4" before the starboard. No vibration though. Plus, as I think I mentioned, my port engine rpms drop slowly from about 5000 on, ultimately settling about 500-600 rpms lower than the starboard at WOT (7600 port vs. 8200 starboard) with the throttle lever together that is. Now, whether my port engine is dropping off at high rpm, my port tach is funky, my cables/throttles need adjustment all remains to be seen. Bottom line is, the boat is going into the shop in spring for a good going over. My fuel gauge finally crapped out, so that needs to be addressed as well. I'll have them do all of the adjustments, plugs, oil changes, lubrication, and fix the fuel sender. One thing I will do next week is swap the tach wires and see what happens. That's a great idea @Gym.

@Billtex2000 , that's exactly what mine sounds like, wind-up toy gears.

 

[Murf'n'surf]

To prove its the gauges, pull the yds connection plug which kills your gauges.

 

[Billtex2000]

Just for the sake of a follow-up...last 4 outings...the noise is gone! Whatever it was must have resolved itself. Thanks for the help.

 

[Big Shasta]

Just for the sake of a follow-up...last 4 outings...the noise is gone! Whatever it was must have resolved itself. Thanks for the help.

Sweet, the Boat fairy princess got to it so you didn't have to worry about it.

(bonus, she's hot too....unfortunately you never get to see her.)