Need Help Diagnosing Engine Noise and Vibration

[Greg__Berger]

Had the boat out this weekend and on Sunday the port side engine was vibrating a lot and making a terrible noise at idle. It ran fine at speed. Here is a video where you can clearly see and hear it.

I checked the oil right away and got no overheat alarms. Didn’t look like any motor mounts were broken. I had to run it for about a half hour following this to get it back to the trailer. Any ideas? Only thing worth noting is that we did get a small stick lodged in the impeller on that side Saturday evening that caused cavitation. I removed and it seemed to run fine. Noticed this the next morning. Where should I start?

 

[buckbuck]

Hard to tell from video but I would crawl under the boat and check the jets for any obstructions and then change the spark plugs. Any rough running on a MR-1 engine can usually be solved by changing plugs.

 

[Ratket]

Could it be the impeller?

 

[Greg__Berger]

Doesn’t appear to be anything in the intake or the impeller and it doesn’t look damaged.

 

[biglar155]

I listened to this half a dozen times with my eyes closed and it could be a clip of my own boat. It's always sounded like that at idle. It's an '09 so I've got the same engines. l bought it as a brand-new leftover in 2010 and I've got about 150 hours on it now.

That rattle noise you hear is the pump.

My thought (based only on the clip posted) is that you don't have anything to worry about. Change the plugs (it'll make you feel better) and enjoy your boating season.

 

[biglar155]

Oh - and for you new MR1 folks: Put a little anti-seize on the plugs (edit: and some dielectric grease on the conector) when you re-install them. You'll thank me later.

Also, you don't have to torque them down like you're King Kong. That's an aluminum block so go easy.

 

[Brad460]

Sounds like a misfire to me...ignition system related - plugs, coil..etc.

 

[Beachbummer]

I suspect you have the most minimal build up in your pump liners. Nothing to worry about, but the next time you pull your pump, you can use your fingers to feel the liner and will likely identify and high spot you can polish with some steel wool to make it go away. I'm not 100% sure but I've had that noise before, and that's how I made it go away.

 

[sunbyrned]

Just curious if you took the impeller completely out to remove the stick or did you do it through the port? 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.

 

[Greg__Berger]

Interesting, thanks a ton for the input! I didn’t pull the impeller. Was able to clear the debris through the cleanout port while we were on the water. Don’t see or feel anything else in there now that it’s on the trailer, but maybe I should pull it.

 

[sunbyrned]

Interesting, thanks a ton for the input! I didn’t pull the impeller. Was able to clear the debris through the cleanout port while we were on the water. Don’t see or feel anything else in there now that it’s on the trailer, but maybe I should pull it.

I would encourage you to. If you haven't done it before, its fairly simple. There's a thread in FAQ section on how to do it. Let us know how it all works out.

 

[Greg__Berger]

Pulled the pump today. Not sure where exactly it came from, but a tiny little piece of the stick that was caught Saturday evening did fall out as we took it apart. Couldn’t find any other debris and all impeller blades and housing looked good so we put it back together and will see how it does next time it’s out!

 

[Gym]

Welcome to the forum @Greg__Berger. I see from the pic you have your "mini me" giving you some pointers. I would think, from your clear explaination, that you have found the culprit. It doesn't take too much to throw these "fine tuned" machines off. The good part about this is you now know what to look for next time and you got some quality bonding time with your son.