plug selection

[blgrams]

I just rebuilt a 40hp 1991 johnson. my dealer gave me Ql78YC (gapped to .030) but the book says Ql78C (gapped to .030) . what is the difference? is this a problem? Is there any change that must be made in the carburetion when both cylinders have been bored out by .030

 

[rickdb1boat]

Re: plug selection

Ql78YC is the correct plug for your motor. The "Y" plug has a slightly longer nose, but it is the right one. Should not have to worry about the carbs..

 

[blgrams]

Re: plug selection

thanks,I read somewhere that one of the orifices needed to be changed if the cylinder is bored out.<br /><br />Bruce