'69 Johnson 33hp Spark Plugs?

[shrubnub]

Bought the motor of a fella on Craigslist. Currently has Champion LV76 plugs in it, and starts and runs moderately well. Went to buy new plugs today, and the research I did indicated that the motor calls for Champion RJC8 or JC8 plugs.

My big issue is, the LV76's don't have the armature over the electrode. I didn't grab the recommended plugs because I wanted to get some opinions on whether to stay with the LV76 plugs or move to the recommended RJC8 or JC8.

Thanks.

 

[racerone]

Should be J6C

 

[shrubnub]

Are you sure? This chart

http://www.iboats.com/Johnson-Champ...5115763--session_id.687046836--view_id.669920

shows the J8C. I'll go with your recommendation, as long as you're sure.

 

[joereeves]

OMC has always recommended the Champion J4C plug, with the alternative being the J6C plug, both gaped at .030 . Due to the engine's age, the J6C would most likely be the better choice as "recerone" suggests.

I have no idea what the J8 might be suggested (I didn't go there). However, the J8 is too hot and will cause piston damage.

 

[shrubnub]

I appreciate you both taking the time to answer. I'll try the J6C's and see how she runs. Thanks!