1994 Johnson ocean runner spark plugs.

[j_luke]

I’ve been attempting to replace spark plugs on my 94’ 150 Ocean Runner (J150EXERV) and have been seeing conflicting information. The current plugs are QL77JC4 but I’ve been seeing lots of catalogs telling me to use QL78YC. Any help would be appreciated.

 

[Vic.S]

I’ve been attempting to replace spark plugs on my 94’ 150 Ocean Runner (J150EXERV) and have been seeing conflicting information. The current plugs are QL77JC4 but I’ve been seeing lots of catalogs telling me to use QL78YC. Any help would be appreciated.

ITYWF that originally the plugs would have been QL77JC4, with QL16V ( surface gap) as an alternative

The currently recommended plugs are QL78YC

 

[j_luke]

ITYWF that originally the plugs would have been QL77JC4, with QL16V ( surface gap) as an alternative

The currently recommended plugs are QL78YC

Ok thanks. I bought a set of QL78YC plugs and found the electrode depth is slightly taller than the 77’s so I wanted to be sure I wasn’t going to slap the piston.

 

[oldboat1]

(I trust everything Vic S says on plug selection.)

 

[Faztbullet]

The QL78YC are used in 60° motors which you have..the L77J4C are for 90° motors