I have 2, 1961 Mercury DR800's and trying to find out what are the correct spark plugs for these motors...The shop manual says J4C for block 833-1919 OR J2J for block 833-1688
Q1..how do I tell what blocks I have?? Q2...most mechanics tell me to use NGK B7S or B9S...instead of Champions
The old plugs look really fouled...like they were too cold...I need someone who has old Merc engines to set me straight..
Thanks
MrMotor, Ontario,Canada
Q1..how do I tell what blocks I have?? Q2...most mechanics tell me to use NGK B7S or B9S...instead of Champions
The old plugs look really fouled...like they were too cold...I need someone who has old Merc engines to set me straight..
Thanks
MrMotor, Ontario,Canada