Reading Glow Plugs - and Informative overview
If the spiral is a little bit pressed and bent it means that the engine has too much compression. If you are racing on a sea level track, with 25% or more nitro this could be the main reason. Than you need to check underhead shims and insert a tenth.
If the coil element has a dull, as if it were sanded, it means that the carburation is too lean (lack of fuel) and you can damage the engine. You run the risk to break the coil element and make it fall down on the top end of the piston, damaging the piston/sleeve. In this case, you should replace the old Plug with a new plug and richen the High Speed needle 1/8th.
If the thread has a dark colour and the plug seems wet, the carburation is too rich and the engine isn't running at optimal power. You have to lean the carburation closing the High speed needle.
When the coil element is polished and the spiral does not present any imperfections, your engine carburation is most likely spot on.
and thats all folks
If the spiral is a little bit pressed and bent it means that the engine has too much compression. If you are racing on a sea level track, with 25% or more nitro this could be the main reason. Than you need to check underhead shims and insert a tenth.
If the coil element has a dull, as if it were sanded, it means that the carburation is too lean (lack of fuel) and you can damage the engine. You run the risk to break the coil element and make it fall down on the top end of the piston, damaging the piston/sleeve. In this case, you should replace the old Plug with a new plug and richen the High Speed needle 1/8th.
If the thread has a dark colour and the plug seems wet, the carburation is too rich and the engine isn't running at optimal power. You have to lean the carburation closing the High speed needle.
When the coil element is polished and the spiral does not present any imperfections, your engine carburation is most likely spot on.
and thats all folks
