Another Spark Plug Question...

[steam_mill]

Motor is a 1954 7.5 Evinrude.<br /><br />Currently running Champion J6J plugs.<br /><br />Reference says JC4.<br /><br />Can't find JC4 but can find:<br /><br />L77JC4 and <br /><br />QL77JC4.<br /><br />Which plug should I use?<br /><br />Tx.<br /><br />Joe

 

[seahorse5]

Re: Another Spark Plug Question...

The factory recommendation from the latest Parts and Accessory Catalog from Bombardier, still recommends the J6C plugs for the 7.5, same as was recommended back in 1954. Back then it was called J6J, now J6C<br /><br />A rule of thumb on the older motors, if it has a thermostat, use a J4C plug. Motors without a thermostat use J6C's.