harmonic vibration

[wishinIwasFishin]

g'day mate's<br /><br />I've got 1973 80hp mercury just fitted to my 16ft f/g boat and did about 3 or 4 hours and it broke one of the bolts that holds the reeds to the crank and than proceeded to swollow it(not pretty) Any way my mech. said that harmonic vibration would cause this! dose this sound right? and how do you stop it

 

[jim dozier]

Re: harmonic vibration

I'm sure that vibration plays a key and harmonic vibrations by their nature are more intense, but I would bet money that since your motor has some years on it, someone has been into the crank case and reed area and those reeds have been out and put back in. One of them was either not torqued properly or the threads were damaged and out comes the bolt. Good luck.

 

[wishinIwasFishin]

Re: harmonic vibration

Thanks jimd <br />for the quick reply <br /><br />I should have added in my first post that this old girl has never been apart as when we pulled it down it still had the little seal that mercury use to use to say that it has never been touched.<br /><br />cheers<br /><br />daryl

 

[clanton]

Re: harmonic vibration

I would use loctite red on the screws during reassembly.