Swear I heard a seized cylinder

[thegrapeguy]

2014 212x - I started the boat up this past weekend for the 1st time after sitting all winter. Didn't fog it either per my local dealer's instructions. They said might screw up sensors.

1st engine turned over but didn't start. Sounded normal though - "thump, thump, thump, thump". 2nd engine turned over but had a different rhythm than the 1st engine. Kind of like a "thump, thump, pause, thump" sound. Didn't start though.

Oops - forgot lanyard. Plugged it in and decided to do the garden hose start. Didn't want to end up in the lake stuck. I was concerned about that 2nd engine though.

1st engine started perfectly. 2nd engine turned over with that different sound and then kicked on but I heard a loud almost metallic bang. Like hitting a pipe with a hammer. Then it started purring. I was relieved but felt that something released in that engine - any chance a cylinder was bound up?

Seems to run fine though on the water...

 

[buckbuck]

I don't recall anyone experiencing this issue. You may want to take oil samples for both engines and send them to Blackstone Labs.
http://www.blackstone-labs.com/

 

[bronze_10]

Valve was stuck maybe?

 

[itsdgm]

I agree with @bronze_10 could be a stuck valve. Ask me how I know It's also possible that something was stuck in the impeller like a stick, or rodent and got freed up.

 

[Gym]

No chance it was a cylinder. You would have broken the crank shaft or it wouldn't have cranked at all. It is possible you had a hung up valve that released or possibly the sound came from the impeller striking the pump liner until it got wet?

 

[Bruce]

The impellers make a lot of noise out of the water. I would bet that is what you heard.

Just to make sure, you turn the water on after the engine starts and off before you stop the engine. Running the water with the engine off can get water into the engine.

 

[Cobra Jet Steering LLC]

yes I also believe it was the pump not the engine , if the liner was swelled it was locking up the pump and causing the engine to drag down when trying to start it. it is a common issue .

 

[BlacklimitedS]

I agree with @Gym and think it was something in the impeller. If a valve was stuck the top end would be damaged and usually the piston will hit the valve. Regardless if it was an internal engine issue it would not clear up and run normal. The good news is you should be fine.

 

[thegrapeguy]

Thanks for replies. When the boat is being turned over without the lanyard in what is taking place? There's no spark being created but what parts are moving? Because I felt there was something wrong right from the beginning with the sound of the engine compared to the other "good" one.

 

[Bruce]

Thanks for replies. When the boat is being turned over without the lanyard in what is taking place? There's no spark being created but what parts are moving? Because I felt there was something wrong right from the beginning with the sound of the engine compared to the other "good" one.

Everything that moves is moving but no power is provided to the spark plugs.

 

[Cobra Jet Steering LLC]

That is it exactly, the ignition is off but the starter is turning, if you look in the pump from behind you will probably see places that show scratches from the impeller hitting the high spots of the liner, these spots are caused by dissimilar metal corrosion going on between the pump liner and the pump housing, when the boat is being used often these spots keep wearing so you don't really notice them but when the boat site for a while it gives them time to expand and make contact with the impeller when you try to start the engine, after you use it the spots wear down again.