Tweet
I purchased a 1983 Johnson 50 HP Model J50BELCTA.
It runs fine and has Champion L77JC4 spark plugs gapped at .040
In the bottom of the pan I found a loose Champion QL77JC4 plug, evidently dropped there by accident, so it must have been running the Q plug at one time. I understand the Q is for a resistor plug.
The tag on the plug wires calls for Champion L77J4, which I understand has been superseded by the L77JC4 which has a copper plated electrode.
My question is: Which plug should I run, and what should it be gapped at ?
I've read various stories on the internet saying the recommended gap is .030 and other places that it is .040 I've also read that the Q plug should be run in these motors.
About 10% of my running will be at idle, or slow trolling, and 90% at or near full throttle.
Which is the best plug for this motor, for smooth running and motor longevity ?
Thanks,
Randy
South Texas
It runs fine and has Champion L77JC4 spark plugs gapped at .040
In the bottom of the pan I found a loose Champion QL77JC4 plug, evidently dropped there by accident, so it must have been running the Q plug at one time. I understand the Q is for a resistor plug.
The tag on the plug wires calls for Champion L77J4, which I understand has been superseded by the L77JC4 which has a copper plated electrode.
My question is: Which plug should I run, and what should it be gapped at ?
I've read various stories on the internet saying the recommended gap is .030 and other places that it is .040 I've also read that the Q plug should be run in these motors.
About 10% of my running will be at idle, or slow trolling, and 90% at or near full throttle.
Which is the best plug for this motor, for smooth running and motor longevity ?
Thanks,
Randy
South Texas
Comment