78 Johnson 15 hp plugs

[Jack Spratt]

Hello, Nice informative website.
My 1978 Johnson 15 HP needs new plugs.
Model 15EL78B
The pugs in it are QL77JC4, but the tag on the plug wire says L78V. Which is right, and what would the gap be?

Thanks,
Another Newbee

 

[rickdb1boat]

Re: 78 Johnson 15 hp plugs

1978 model would use QL77JC4 gapped at .030....They do list the surface gap plugs also, but I would use the above for best operation under all conditions

 

[Jack Spratt]

Re: 78 Johnson 15 hp plugs

Thanks for the prompt reply, Rick
Helps make the sport more fun when you
find a hepful site like this.

Thanks again
Jack

 

[rickdb1boat]

Re: 78 Johnson 15 hp plugs

No problem, Jack. Good little motor ya have there.....

 

[Scaaty]

Re: 78 Johnson 15 hp plugs

I have a 79 15 kicker on my 25 footer. Cost of filling the 90 gallon tank has the little puppy in the water more and more with an extension tiller handle and me sitting on the live well lid just a fat and happy as when the v-8 is running underneath. Don't need no stinking speed, just sun! Great motors, but I would stick with the 77 plug...haven't tried a gapless in there, and I'm sick of inventing the wheel, which at this rate, we will make square yet