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Help - port engine making rattling sound

dzeppos

Jetboaters Lieutenant
Messages
270
Reaction score
162
Points
172
Location
Coto de caza, CA
Boat Make
Yamaha
Year
2016
Boat Model
Limited S
Boat Length
24
[USERGROUP=9]@HELP[/USERGROUP]
I’m on lake perris - heading s clanking sound from port engine. Nothing in clean out ports. Maybe wood chips. (No engine light came on but bad sound) Tried reverse forward slam technique - seems like sound isn’t as bad But still clicking Motoring back on other engine. Any advice ? Boat is 16 242ls
 
Wanted to respond so you know someone is reading this.

Based on the description, it sounds drive-related, rather than internal engine. If you were describing a loud knocking sound, rather than a clanking sound, I'd say maybe internal like a rod bearing or piston. While I guess a timing chain could sound like that, if the chain broke the engine wouldn't run. If you lost a chain tensioner, you'd probably be jumping the timing chain, and again the engine likely wouldn't run.

Take it slow going back/clamp off the water intake to prevent engine damage, and get it out of the water to take a look. Perhaps an impeller blade got bent or something else is contacting in the jet pump. Hopefully something obvious and easily fixable.

Jeff
 
I just posted this same response on another thread. Today must be the day for this issue.

I had something similar and I thought I got everything out, but it still vibrated. I ended up taking the impeller out, didn't find anything and put it back in. That fixed it. For me, either something fell out then and I didn't see it or the gears and the impeller grooves were out of sync and they got back into sync through that process. Something to consider at least.
 
Wanted to respond so you know someone is reading this.

Based on the description, it sounds drive-related, rather than internal engine. If you were describing a loud knocking sound, rather than a clanking sound, I'd say maybe internal like a rod bearing or piston. While I guess a timing chain could sound like that, if the chain broke the engine wouldn't run. If you lost a chain tensioner, you'd probably be jumping the timing chain, and again the engine likely wouldn't run.

Take it slow going back/clamp off the water intake to prevent engine damage, and get it out of the water to take a look. Perhaps an impeller blade got bent or something else is contacting in the jet pump. Hopefully something obvious and easily fixable.

Jeff
Thanks for the info. I went at no wake speed back to dock - only 2 miles (left bad engine idling too - didn’t sound bad at idle - only when you rev hard. - pulled it out - can’t see anything. But something doesn’t sound right. May need to take to dealer - just not very mechanically included to start pulling the pumps off.
First problem in 145 hours of boating since i bought her 3 years ago. Par for the course. Not a big deal.
 
@dzeppos Are you operating in fresh or salt water? While your boat is on the trailer and throttle in forward look closely at the impeller and impeller liner for the affected side. If this noise is not caused by debris it could be a swelled liner or bent impeller blade impacting the liner. If that's the issue you should see impact or worn spots on your liner. The impeller blades may also have a rough burr on them if you run your fingers over them.
 
Fresh water lake-reservoir. A clean lake too. I had front beached it earlier in the day - but still boated for a good 2-3 hours thereafter taking the kids wake surfing. I listen to the engines (no music) - no issues so i would of noticed any issues Then, after 3 hours - All of sudden heard clanking/sound (from the port engine picking up a wakesurfer (no warning lights went on).
For a second - the reverse slam forward thing after two attempts mitigated the noise but didn't eliminate it. Engine seem to run at partial power - probably cavitation. I got it out no issues and now that its daylight, I'll look underneath a bit more closely this afternoon and check the impeller blades. Thanks to all for their input - first problem ever after 3 years of solid boating on my 242 - it happens to all of us at some point. thx
 
Fresh water lake-reservoir. A clean lake too. I had front beached it earlier in the day - but still boated for a good 2-3 hours thereafter taking the kids wake surfing. I listen to the engines (no music) - no issues so i would of noticed any issues Then, after 3 hours - All of sudden heard clanking/sound (from the port engine picking up a wakesurfer (no warning lights went on).
For a second - the reverse slam forward thing after two attempts mitigated the noise but didn't eliminate it. Engine seem to run at partial power - probably cavitation. I got it out no issues and now that its daylight, I'll look underneath a bit more closely this afternoon and check the impeller blades. Thanks to all for their input - first problem ever after 3 years of solid boating on my 242 - it happens to all of us at some point. thx
Your report is VERY similar to what I experienced a few weeks ago, when it turned out the rear bearing on the port side had retired (the one immediately under the cone). It sounded fine at idle, but was definitely metal on metal at higher rpms. It sounded (and vibrated) much like previous times when it was just something stuck or wrapped around the impeller. I would check the bearing, or ask the dealer too.
 
May need to take to dealer - just not very mechanically included to start pulling the pumps off.
First problem in 145 hours of boating since i bought her 3 years ago. Par for the course. Not a big deal.

that's one of the best features of these boats is you don't have to be very mechanically inclined to do some basic trouble shooting and often the repair,

If you don't have the time or have the money for a dealer to fix that's great but if you have a basic set of wrenches you can easily pull the nozzle/impeller/shaft and open the cone to at least view the bearings, If it all looks good put it back together and give it a water test, maybe an hour total, with videos and instructions in the FAQ,

.
 
Thanks Scott,
I've come along way in learning about my boat. I still have my YES warranty, and if it is bearing/shaft failure vs. something in there - perhaps it will be covered. But doing test runs on the boat are challenging as I'm at least 75 minutes away from the closest boat lake (other than the pacific ocean - but that's not as easy for testing the boat out). I'll do another inspection, but for time/money factor - its cheaper for me to have the dealer work on it than me taking time off from work. The website is awesome - thanks to all
 
[USERGROUP=9]@HELP[/USERGROUP]
I’m on lake perris - heading s clanking sound from port engine. Nothing in clean out ports. Maybe wood chips. (No engine light came on but bad sound) Tried reverse forward slam technique - seems like sound isn’t as bad But still clicking Motoring back on other engine. Any advice ? Boat is 16 242ls
You already heard it from @Scottie - pull the pump and the cone, check the main pump bearing! I would not run it like this.

--
 
Try a couple pumps go grease to the intermediate bearing. My 09 would sound noisy but would quiet down with a couple pumps of grease. The Yamaha mechanics said I was crazy, but it worked. the sound was always at idle and would stop when the pumps were under more of load.
 
Ok. Can’t believe i didn’t see it the first time but found piece of wood lodged in impeller. Do i remove the grates? (Is it as simple as lossening bolts). What tool you recommend i use to remove wood without scratching impeller?
 

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Ok. Can’t believe i didn’t see it the first time but found piece of wood lodged in impeller. Do i remove the grates? (Is it as simple as lossening bolts). What tool you recommend i use to remove wood without scratching impeller?
Pulling the pump would be the easiest
 
Yes, pull the pump. I didn't do so the first several times I had pieces of wood like that. Struggled, pulled the grate one time, spent hours pulling things.

Then I pulled the pump one time. Geez. So easy. I wasted sooo much time and effort doing it the other way. You don't need to take the impeller off the pump. Just pull the pump and remove the debris. Easy peasy.
 
Ok. Can’t believe i didn’t see it the first time but found piece of wood lodged in impeller. Do i remove the grates? (Is it as simple as lossening bolts). What tool you recommend i use to remove wood without scratching impeller?
I would pull the pump, you will not be able to clean it properly otherwise.
This thread has some pics and tips on pump reemoval for your boat:

--
 
The whole time I was reading this I was waiting for the picture of a piece of wood wedged in the impeller. That was my first guess sometimes they are even smaller and I had one get wedged on the back side of the impeller no sound but made cavitation. Kind of a rare occurrence but they suck a lot of water into that jet nozzle. The forward reverse move probably just ground it down but the wood fibers are strong it looks like a long pair of needle nose pliers could be used to pull it out if not like all the above mentioned pull the pump it’s easy.
 
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Wow. that's not a piece of wood, that's a lumberyard in there. Our buddies here are right on. Pull the pump. It sounds scary but it's very easy and straight forward. My first time was a little slow and scary but after that time I felt I was an expert and have done it several times since.
 
Update - there were 2 pieces of wood !!- the other was like a thick branch - dug in really hard into port impeller. It’s amazing it got through the grate (like 1 and 1/2 inch thic by 5 inches - huge - - I had a jet boat repair guy do it because i feared - the impeller blade was nicked and they trimmed it. It took a few minutes just to dislodge the wood off the impeller once they removed it.
Well - first incident in 150 hours. Also had them put on the Magnum AK on align the steering cables. Can’t wait to take out again Monday. Thx again to everyone for their input.
 
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