34 • SLAYER PRO 4X4
If the engine is worn or
damaged enough to require
replacing the piston,
sleeve, or connecting rod,
consider exchanging your
old engine for a brand new
engine under the terms of
the Traxxas Lifetime Engine
Replacement Plan (ERP). It
could save you time and
effort. Details are in your
model’s documentation
package.
The TRX 3.3 Racing Engine
is designed to be easy to
rebuild. Critical engine
components such as the
crankcase, crankshaft, and
engine bearings are made
to extremely high-quality
standards and should under
normal circumstances
outlast multiple sets of
pistons, sleeves, connecting
rods, and wrist pins
(reciprocating assemblies).
It could be more economical
for you to continue to use
your good bearings and
crankshafts, and simply
replace the reciprocating
assembly as needed. Engine
assembly is not difficult and
replacing the reciprocating
assembly does not require
any special tools or skills.
Your Slayer Pro 4x4 requires timely maintenance in order to stay in
top running condition.
Neglecting the maintenance could allow dirt,
deposits, and moisture to build up inside the engine leading to internal
engine failure.
The following procedures should be taken very seriously.
After each hour of running:
• Clean and re-oil the air filter. The instructions for this procedure are on
page 19.
We cannot stress enough the value of cleaning your air filter
at the scheduled intervals.
The cleanliness and condition of your air
filter directly influences the running life span of your engine.
Do not
skip air filter maintenance!
• Clean the outside of the engine of accumulated dirt, oil, and grime.
Accumulated grime will decrease the engine’s ability to cool itself.
• Tighten the wheel nuts (especially on the left side). Use the 8mm end of
the included glow plug wrench.
After each running session:
• Perform after-run maintenance on the engine. This clears the engine
of destructive moisture and other corrosive deposits. This is extremely
important for the life of the engine. Read on for after-run maintenance
procedures.
• Inspect the gears for wear, broken teeth, or debris lodged
between the teeth
• Inspect the vehicle for obvious damage or wear. Look for:
1. Loose or missing screws
2. Cracked, bent, or damaged parts
3. Cut or loose wiring
4. Cut or kinked fuel lines
5. Signs of fuel leakage
Other periodic maintenance:
• Connecting rod: The connecting rod should be replaced when the
piston and sleeve are replaced. Also replace the piston wrist pin and
G-clip whenever the connecting rod is replaced. As with other internal
engine components, connecting rod life depends engine’s usage and
the quality and frequency of the engine maintenance. Inspect the
connecting rod after 3 gallons of fuel have been used.
• Slipper clutch pads (friction material): Under normal use, the friction
material in the slipper clutch should wear very slowly. If the thickness
of any one of the slipper clutch pads is 1.8mm or less, the friction disc
should be replaced. Measure the
pad thickness using calipers or
measuring against the diameter of
the 1.5 and 2.0mm hex wrenches
provided with the model.
• Piston/sleeve: The life of the piston
and sleeve will vary greatly with
how the engine was used and maintained. The piston
and sleeve should be replaced when they no longer
seal effectively (loss of compression). Symptoms
include the engine being difficult to start when warm,
stalling when warm, and stalling when throttle is
suddenly closed to idle. Replace the wrist pin and
G-clip whenever the piston and sleeve are replaced.
After-run Procedure
You must perform after-run maintenance on your
Traxxas engine whenever the model will be stored for
longer than a few hours. Taking the time to prepare
your engine for storage will reward you with longer
engine life, easier starting, and better performance.
When a nitro engine is shut off, some excess unburned
fuel remains in the engine. The methanol in model
engine fuel is hygroscopic, which means it easily
attracts and absorbs moisture. This moisture can cause
rust and corrosion on the steel engine parts (crankshaft,
bearings, wrist pin and starter shaft) if the fuel is not removed from the
engine. There are after run oil products available from your hobby dealer
or you can use WD-40
™
, a common household lubricant. To ensure
your TRX 3.3 Racing Engine is protected from internal corrosion, use the
following procedure:
1. Whenever possible, shut off the engine by pinching the fuel line
closed. This allows most of the excess fuel to be consumed by the
engine. Be sure the throttle is in the idle position. You may have to
pinch the fuel line closed for several seconds before the engine stops.
2. Completely empty the fuel tank. Use your fuel-dispensing bottle to
suck out the old fuel. Do not mix the old fuel with your fresh fuel
supply. If you leave fuel in the tank, transporting or handling your
Slayer Pro 4x4 may cause fuel to run into the engine.
MAINTAINING AND STORING YOUR SLAYER PRO 4X4
17
