Trojan Boat Forum

Took the F-36 out for the first cruise and the starboard engine ran great. I did notice a knocking sound coming from th starboard side of the port engine. I took off th valve cover, everything looked fine, changed plugs and it still knocks. Any idea what this old be. I'm crossing my fingers hoping it's something minor but I'm scared to death.

Thanks,
Brian

Well.....if it's a deep knocking sound it could be bad like maybe a rod knock. Try listening with a long screw driver or better yet an engine stethoscope. Listen in different places and you should be able to get pretty close to the origin......valve train noise isn't what I'd call a knock, higher pitch......good luck and I hope it's not a rod...........John

+1 plus did oil pressure change ? if it's a deep knock change oil filter and cut old one open and start looking for metal in it.

What Tony said, and use a magnet. Of course a magnet doesn't work with some metals but you might pick up some small shavings. You can also use gasoline in a pan to delute the oil to find metal, like panning for gold, without the fun factor.

yep panning for trouble

Is it knock in gear ? out of gear ? low rpm or high ? all rpm ? hot or cold ? Is it running smooth ?

oil in good condition ? good pressure ?

I know thats a lot of questions but hard to give you a opion without full info ( and not hearing the noise )

Good oil, pressure seems good, really sounds more like a tick tick tick than a knock. I tried the screw driver trick put can't seem to pinpoint it and I don't want to run it too long if it's doing any damage. Thanks for all the advice so far.

Fuel pump on the strb side. Take a listen and see if it's coming from there. Could also be a colapsed lifter. We'll keep the worse case scenario for last!

tick tick tick is better than knock knock knock, lifter could be a good cause. Hopefully it's stuck and might free up seein' how it was the first time out

Great info. I'll start digging in.

Yep, tick, tick ,tick is way better than knock, knock, knock.......I would suspect the valvetrain as already suggested.......

Lets hope for a tick.

Mine both had a tick noise until they warmed up on the first run this season. Lifter probably stuck until they warmed up and enough oil made it to the top end. Just run at idle fir a while and let them get up to normal temp. Should go away.

A quart of Marvel Mystery Oil does wonders !!

Great...I mean GREAT news today. just a manifold gasket! Need to get one but I can run it now without fear that a rod will come slamming through the side of the engine. Thanks for all of the advice guys!