Xray NT18 0.8cc, Instruction And Safety Manual

Page: 19 / 26

19
FINE-TUNING THE CARBURETOR
After your engine has been properly broken in and tuned at the track, be aware that changes in weather (temperature,
humidity, barometric pressure), altitude, and fuel nitro content will affect the performance of the engine. See the table below
for guidelines on how to adjust your engine’s carburetor settings to compensate for these various changes.
When… does this… change main needle setting…
Temperature decreases richer
increases leaner
Humidity decreases slightly richer
increases slightly leaner
Barometric pressure decreases leaner
increases richer
Altitude lower richer
higher leaner
Fuel nitro content (%) lower leaner
higher richer
ENGINE TROUBLESHOOTING
Engine spins but will not start:
• Make sure your glowplug starter is fully charged and is properly connected to the glowplug. If the starter is fully charged,
replace the glowplug.
• Verify that fuel is getting to the carburetor. Remove the fuel line from the carburetor and see if there is fuel in it.
• Check your carb settings. It may be necessary to adjust the carb settings if the weather has significantly changed since
the last time you ran the engine.