1973 65hp Evinrude (spark plugs)

[Rod Holder]

Hi all,<br />I just picked up this OB and I'm trying to figure out what the ideal plugs s/b. The ones in it are L77JC4. Owners manual says<br />UL77V. Repair manual says UL74V. I'm about<br />to fire it up for the first time and just want to make sure.<br />Any ideas ???

 

[DP]

Re: 1973 65hp Evinrude (spark plugs)

My NGK book Shows a B7HS which is the same as a Champion UL77JC4.

 

[alcan]

Re: 1973 65hp Evinrude (spark plugs)

Hi Rod Holder<br /> The book calls for UL77V. I belive these plugs are a surface gap plug. It also calls for L77JC4 to use for sustained slow operation. I do alot of trolling with my motor. I have used both types and can not tell any differance in performance. You will have to experiment to see which works best.

 

[Rod Holder]

Re: 1973 65hp Evinrude (spark plugs)

Thanks for the info. I think I will stick with the JC4's until I'm ready for some <br />cruising and switch to the gapless.<br /><br />Have a good one..............