Carburetor Factory Setting; Glow Plug - HPI Racing Savage X 4.6 RTR Manual

2-10
Carburetor Factory Setting (Break In Setting)
High Speed Needle, Idle Adjustment Screw and Low Speed Needle are
designed to be set flush with the carburetor body. This makes it easy to
reset the carburetor to the Factory Break In Setting if needed.
Attention
When needle is over tightened , the
needle is damaged.
2-11

Glow Plug

How Glow Plugs Work
Unlike full sized car engines that use spark plugs and a distributor to fire the cylinders in the combustion cycle, glow engines rely
on glow plugs. In a Nitro engine, ignition is initiated by the application of a glow igniter. When the igniter is disconnected, the heat
inside the combustion chamber keeps the glow plug filament glowing, firing the next cycle, thereby keeping the engine running.
Ignition timing in a glow engine is automatic. At higher RPM's the plug becomes hotter, firing the fuel/air mixture earlier. At lower
RPM's the plug becomes cooler, firing the fuel/air mixture later. Since the glow plug performs so many important functions,
proper plug selection and maintenance are crucial to a properly running engine.
Proper Glow Plug Selection
Proper glow plug selection depends on several factors: Fuel
type, nitro methane content, weather, and altitude can drastically
affect performance. Finding the best combination of fuel and
plug temperature for your driving condition is the key to getting
the maximum performance out of your Nitro Star Engine.
Extending the Life of your Glow Plug
To maximize and extend the life of your glow plug follow these simple tips;
Remove the glow igniter when using more than 1/2 throttle or if the engine does not start after a few seconds.
Do not run the engine lean, lean conditions will overheat the plug causing the element to be damaged or fail.
Use the best Fuel/Plug combination for your driving conditions.
Use a fuel that has a lower nitro content.
When to Replace the Glow Plug
Fuel and temperature will have an effect on the performance,
reliability, and life span of the glow plug and therefore it
should be considered an expendable engine component.
Aside from burnout or plug failure, there are several signs that
can indicate the plug should be replaced.
Plug filament/plug body is discolored or the surface is rough.
Plug filament is distorted or bent.
Engine cuts out when idling.
Engine becomes difficult to start.
High Speed Needle
Flush
Outdoor Temp Glow Plug
Hot
Cold
Checking glow plug
Glow Plug
Hot!
Glow Plug Igniter
16
Idle Adjustment Screw
Glow Plug Characteristics
Cold plug will have better mid,
Glow Plug Cold R5
high RPM power and will last
longer at high temperature.
Glow Plug Medium Cold R4
Hot plug will be easy to start and
stable for tuning. But will fail
sooner at high engine temperature.
Glow Plug Medium R3
Filament
Good Plug Bad Plug
Element glows Element may be
Pliers
when tested. damaged or broken if it
doesn't light up
completely.
Low Speed Needle
Bad Plug
Element is broken or
doesn't light up at all.