Port engine knocking

dodgeem · Post by **dodgeem** » Sat Apr 23, 2011 11:32 am

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

jddens · Post by **jddens** » Sat Apr 23, 2011 12:10 pm

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

alexander38 · Post by **alexander38** » Sun Apr 24, 2011 6:21 am

+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.

wowzer52 · Post by **wowzer52** » Sun Apr 24, 2011 9:51 am

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.

alexander38 · Post by **alexander38** » Sun Apr 24, 2011 11:39 am

yep panning for trouble

prowlersfish · Post by **prowlersfish** » Sun Apr 24, 2011 1:46 pm

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 )

dodgeem · Post by **dodgeem** » Sun Apr 24, 2011 5:32 pm

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.

Big D · Post by **Big D** » Sun Apr 24, 2011 6:16 pm

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!

alexander38 · Post by **alexander38** » Sun Apr 24, 2011 6:31 pm

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

dodgeem · Post by **dodgeem** » Sun Apr 24, 2011 6:48 pm

Great info. I'll start digging in.

jddens · Post by **jddens** » Sun Apr 24, 2011 11:30 pm

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

prowlersfish · Post by **prowlersfish** » Mon Apr 25, 2011 7:08 am

Lets hope for a tick.

TADTOOMUCH · Post by **TADTOOMUCH** » Mon Apr 25, 2011 9:42 am

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.

Lawman · Post by **Lawman** » Wed Apr 27, 2011 11:30 am

A quart of Marvel Mystery Oil does wonders !!

dodgeem · Post by **dodgeem** » Fri Apr 29, 2011 8:47 pm

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!

Trojan Boat Forum

Port engine knocking

Port engine knocking

Tick tick tick