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sudden sound on starboard side, rough running ...

Rdizy

Well-Known Member
Messages
8
Reaction score
11
Points
52
Location
Toronto, Ontario
Boat Make
Yamaha
Year
2005
Boat Model
SX
Boat Length
23
We had been out in the boat a good chunk of the afternoon -- and were tubing the kids back. Suddenly, when accelerating there was a bit of a bang from the right engine (i think) and it sounded really rough and noisy at about 4000 rpm .. i throttled back immediately (thinking maybe we sucked in the rope or something -- but we hadn't).

i turned off the engines.... took out the cleanout plugs, but nothing in there really .

The engines still both start totally fine, and sound perfectly normal at idle, and even at the first forward stop (was very close to our dock, so it didnt take much to get home). The port engine throttles up normally, but the starboard makes noise at about 4000 rpm (not that i have tested it much!). Oil levels were normal when i checked them yesterday.

Any ideas???
 
Something as small as a toothpick or a piece of fishing line in that jet could be causing cavitation.
 
glad to have you on board, pull it out and look at it from the top and bottom to see if you sucked something up, then take it out and test it again, if it is something it could fall out when you load it on the trailer and you'll never even know it, it will just start working right again,

Be sure to check our FAQ for lots of great info,
 
Thanks ... do sounds like people think it is likely in the pump rather than engine? if so, i need to get it on a trailer --- which means about 1 km away. can i drive it slowly without doing any damage? everything SOUNDS fine at very low (sub 3000) rpm ... or do it have to figure something else out?

i see in some of the postings advice not turnover the motors if something might be in there ...
 
If it sounds ok I would turn it on and let it idle while you use the other engine for propulsion back to the dock,

You don't want to run on just one engine, it could allow water to back up and damage the non running engine,

you should also look up through the grates for any loose silicone around the pump housing,

When I had that problem it would idle fine but as I applied rpm's the suction of water through the pump pulled the loose silicone allowing air/cavitation to make it vibrate and sound like the boat was coming apart,
 
Have you pulled the cleanout plug and felt for anything in the jet? If so perhaps try checking again.

Cavitation should cause vibration and noise felt and heard throughout the boat.
 
i did pull the cleanout plug ... there was a bit of seaweed (we have a lot of weeds in this lake, so i am very used to that problem) ... but not much at all (certainly much less than many other times).
 
ok ... go the boat on the trailer ... yup, there is a golf ball in it!! ;) (Now, i have found out that some yahoo on the lake was hitting floating golf balls out!!)

it does look quite as badly jammed in there as one that i saw on another post ... i guess i will be pulling the pump out. i have already watched a couple of videos of that ... doesnt seem too hard..
 
Pulling the pump is easy.

Use thread sealant on the bolts and moly grease on the splines when you reassemble.
 
ok ... go the boat on the trailer ... yup, there is a golf ball in it!! ;) (Now, i have found out that some yahoo on the lake was hitting floating golf balls out!!)

it does look quite as badly jammed in there as one that i saw on another post ... i guess i will be pulling the pump out. i have already watched a couple of videos of that ... doesnt seem too hard..
WELL THERES YOUR PROBLEM!!!
 
@Rdizy Told you, didn't I?
Happy to have you here. What @Bruce said.
Not difficult at all. Please post pics if you can.
 
I wish mine was a golf ball. Probably a month or so, before I get to pull the engine out at best.
 
Well, followed directions to pull out the I found here -- and all seems good!! Thanks to @swatski for suggesting this (i am also a refugee from another board ;)) ... Have it back together, and back on the water -- and everything seems great!! (other than the stutter step of forgetting to put the starboard cleanout plug back in --- but that was easily fixed!). Doesn't look to me like the blade was bent -- but i do see a few chips or marks in the leading edge of the blades ... is this normal w

Here are a few pics ... including some of the leading edge of the blades

 
Thanks everyone!! This saved the next week of our vacation -- feels like the boat is back to normal
 
You made quick work of that problem!
 
Thanks everyone!! This saved the next week of our vacation -- feels like the boat is back to normal
Welcome aboard! Glad you made it to the freedom forum! The only reason to go back "there" is to tell anyone you care about where you'll be from this day forward! Glad we could help. Cheers!
 
Wow! I had several guesses as to what could be causing your issue. A GOLF BALL was not one of them! Nice job on the fix and thanks for reporting back.
 
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