[yarcraft91]

Dunno about the Faststrike label.

I have a 1991 120 Johnson. Last year, I was having some running problems, poor starting, too-fast and unsteady idle speed, stalling in gear, all indicating a lean-running condition. So I did the following:
- Replaced spark plug wires.
- Changed spark plugs from QL77JC4 to QL78YC (dealer-recommended update).
- Torqued the carburetor and manifold bolts (several were loose).
- Removed black pulse dampener driving the fuel pump, replaced with blue pulse dampener (blue dampener is a factory-recommended update, part numbers appear to be the same)
- Checked/adjusted the timing (was 4 degrees over-advanced). Funny story here...
- Re-torqued the head bolts (none loose).
- Replaced the entire fuel hose (needed!). Found and replaced 2 broken fuel hose clamps! Check every one of them!
- Checked head temperatures (all fine).
- Decarboned with Seafoam.

Runs just fine now! Can't think of anything I did that isn't a good maintenance item at this motor age. I've owned it since new and it's been a great outboard!

On the spark plugs, the QL78YC is a bit hotter than the standard factory plug, which helps because I rarely run the motor at WOT, usually cruising at 3000-4000 rpm. I've had the same recommendation from others familiar with this motor. Another recommendation was to use the QL82YC, which would be hotter yet- I'm told that was the standard plug in older versions of my motor.