Knocking from Mercruiser 5.0, please help! /W Video

[krille_krille]

​Engine/Drive started all of a sudden to rattle after wake boarding. When in gear and revs over 1500rpm the engine starts knocking, does not sound pleasant.... This is only in gear, when in neutral and rev there is no knocking sound. That should point towards the drive?​

Please help me identify the problem with the help of the videos .


First video is at 2500rpm in gear. - http://www.youtube.com/watch?v=t5LZSimNYL4


Second video is revving in gear from 1000-2500 - http://www.youtube.com/watch?v=Bk_iJY8_xzg


third and last video is at idle, something is loose. - http://www.youtube.com/watch?v=z68x9tiMCQQ


What could the problem be? All help is appreciated.




Engine - Mercruiser 5.0 with Alpha one drive.

 

[guyjg]

What year and SN? Anything loose on the front of the engine...pulleys?

 

[Bt Doctur]

Almost sounds like a loose pushrod or rocker arm.

 

[Docksidemarineservices]

Sounds like a lawnmower, never a good thing, May be time to remove it and pull her down.

 

[krille_krille]

What year and SN? Anything loose on the front of the engine...pulleys?

Nothing loose what i can see. The serial number on the engine is "0L090832"

Can it have anything to do with egnition timing being wrong?

thanks.

 

[guyjg]

Boat Dr. and Chris have years of experience for you to head. You didn't provide a year...the engine could just need valve work or it may just be very tired and needing to be put to rest. If you are not engine savvy then you need to take it to a reliable mechanic for a proper diagnosis.

 

[crc]

Im with Bt Dr. it sounds like a broken valve spring/push rod...other than that good luck. Find a reputable marine mechanic.

 

[Master mechanic]

Maybe a spark plug wire fell off ?

Compression test first with all the plugs out. On a warm engine and the throttle fully down. Screw in tester.