502 vibration @ 1100 rpm.

[brettokok]

502 merc multiport that I just replaced all rocker arms on due to one cracking.

Idles smooth. vibrates @ 1100rpm and up in or out of gear. Didnt even drive on water after rocker arms being replaced. Have ran in driveway and on trailer while lowered in water. any guesses on what it might be?

 

[Bondo]

Re: 502 vibration @ 1100 rpm.

any guesses on what it might be?

Ayuh,...Possibly a screwed up installation,..??..??

Run it up to 1100rpms,+ pull each plug wire til you find the offending cylinder....
Then find out Why it's skipping....