The spark plug of your Cifarelli machine plays a fundamental role for the engine, not only for its reliability, but mainly for the performance. We often look for the cause of engine’s malfunction (ignition failure, irregular RPM, etc.) while it would be enough controlling the spark plug to resolve the problem.
How long haven’t you disassembled the spark plug for a simple inspection?
In normal conditions remember that the spark plug must be inspected about every 25 hours of working and must be cleaned every 50 hours. For this reason each Cifarelli machine is equipped with a spark plug key.
If your machine is a mist sprayer or a blower series 3, to reach the spark plug is enough to detach the terminal.If you have a shaker, before disconnecting the terminal you must unscrew the knob of the spark plug case, using the spark plug key.
If your machine is a BL6S blower, you have to use the spark plug key on the crosshead screw driver side to unscrew the spark plug cap screw.
Observe the electrodes (the one with an arched form and the central one); under normal conditions of working, a spark plug shows it like in the picture: electrodes are tidy and white/grey color. If the electrodes are black or covered with soot, it means that the mixture you are using is too rich in oil or that the air filter must be cleaned. However, I don’t want to dwell me on spark plug aspects because a lot of web sites deal this subject with illustrations.
Remember that every 50 hours of working you have to clean the spark plug. After having removed it, brush electrodes using a brush with brass bristles and if it’s possible, blow it with compressed air to eliminate all residues.
After having cleaned it, measure with a feeler gauge the distance between the two electrodes: it must be within 0.5 and 0.6 millimeters.
In case the central electrode and the mass one are too rounded and their gap is enlarged, the spark plug must be replaced, however we recommend its substitution after about 100 hours of working; in this case, don’t mount any spark plug; the correct one must be CHAMPION RCJ6Y. You can use different brands of spark plugs, however of the same typology, for ex. BOSCH WSR6F or NGK BPMR8Y; the using of different spark plugs causes serious engine damages to your machine.
The last recommendation: remember that the spark plug reaches very high temperatures during the functioning of the engine. Wait for its cooling before disassemble it.