knock/grind/rattle at speed 90HP etec please help!

flynavy812

Cadet
Joined
Jun 12, 2016
Messages
13
Hello all, I need some serious help. 2015 etec 90HP, 277 hours.

Above around 3000RPM I’m getting a noise. Hard to tell if it’s powerhead or lower unit.

It’s intermittent and doesn’t really follow a trend or pattern. Best I can explain it, sounds like something loose hitting the hull which I double checked. I have provided a video, you may need to turn volume up but the noise is present. My fear is it’s engine related and I’m screwed. For what it’s worth, no power issues and engine runs great.

 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,674
Drain gear oil and look for metal bits.------And you can run with a timing light ( 1 cylinder at a time ) to see if there is an ignition issue.------Changed fuel filters ?-----New water pump impeller installed.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,931
Check to see if trim tab is loose and if play in upper motor mounts. If motor lean back when put in gear or accelerating it will cause the shift rod to rattle against the adapter plate
 

flynavy812

Cadet
Joined
Jun 12, 2016
Messages
13
Drain gear oil and look for metal bits.------And you can run with a timing light ( 1 cylinder at a time ) to see if there is an ignition issue.------Changed fuel filters ?-----New water pump impeller installed.
Check to see if trim tab is loose and if play in upper motor mounts. If motor lean back when put in gear or accelerating it will cause the shift rod to rattle against the adapter plate
suggest you submit same topic on the I3 ETEC owner's board for E-TEC expert support. see their SEARCH utility


Thanks guys, sorry just saw this. Drained LU oil, all green and mild shavings. Motor mounts seem solid.

It appears to come in above 3000RPM and maybe come on quicker as I trim. Today, for the first time I had a “surge” at WOT and I backed off real quick scared it was gonna blow. Engine didn’t act weird at all, almost felt like prop slipped or cavitated.

Running on muffs in N, I hear the SAME tick/knock but I know how this goes and this could be anything, ugh!
 
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