START UP
1. Always remove Tube(A) at the check valve first
before fueling. The fuel tank is pressurized and you
need to relieve the pressure first. Disconnected
Tube(B) at the filter and fill the tank. Reconn-
ect Tube(A) and (B).
2. From the fully closed (clockwise) position, turn the
needle valves counter clockwise as follows.
3. Close the throttle to the idle position and connect the
glow plug driver. The engine is now ready for starting.
●
Hover Needle
2 times open / 1.0~2.0
●
Idling Needle
Factory Set ( 0.5 ) / 0.2~1.0
●
High Needle
Factory Set (1.0 ) / 0.5~1.5
BREAK-IN
It is not necessary to mount this engine on a set stand
for break-in. However, the engine should be adjusted
slightly on the rich setting ( Hover Needle 2 times open)
for the first few flights to insure proper break-in. Always
use a good quality fuel which contain 15 ~30% nitro-
methane and an oil content of 18 ~23% low viscosity oil.
SPECIFICATIONS
Bore
23mm
Stroke
22mm
Displacement
9.14cc
Weight
406g
Practical rpm
2,000 ~20,000
OPERATOR’S MANUAL ( YS0015)
56SR
(Helicopter Engine)
FEATURES
The 56SR is the latest in helicopter engine technology
from YS.
●
New stroke design for superior operation
●
New carburetor design for easier adjustments.
●
Factory preset fuel regulator.
INSTALLATION
1. The fuel lines should be connected to the fuel tank
as shown in the above figure. Be careful to install the
check valve in the correct direction. Since the tank is
exposed to high pressures, be sure that all conne-
ctions are tight to prevent pressures leakage.
2. Since the engine is sensitive to dirt in the fuel, a fuel
filter must be used.
3. Tube(C) should be set exactly at 35mm between
the engine and check valve. DO NOT use any oth
er type of check valve. The check valve is de
signed exclusively for the 56SR.
4. Adjust your throttle linkage and curve using the align-
ment indentations on the carburetor body located on
the throttle arm side of the carb body.
PLEASE NOTE that the hover position is at 40% see
FIG 2.
NEEDLE VALVE ADJUSTMENT
Idle, Hover and High needle valves all work the same
way. Turning the needles clockwise will lean the fuel mix-
tures and counter clockwise will richer the fuel mixtures.
1. Set needles as described in START-UP.
2. Start the engine and check idle. Adjust as needed.
3. Lift helicopter into a hover and check for the correct
rotor RPM recommended by the kit manufacture.
Once this is done take note of the amount of smoke
being produced by the muffler. The mixture is correct
for hover when there is a steady stream of smoke be-
ing produced.
4. Land the helicopter for approximately 20~30 seconds.
Lift the helicopter into a hover again taking note of the
transition from idle to hover. If the engine exhibits a
large amount of smoke and the throttle response is
sluggish, you will need to adjust the idle and or the
hover needle leaner to achieved a smooth transition.
If the engine detonates and the smoke is inconsis
tent or a small amount is produced, the mixture is too
lean.
5. High Needle refines the fuel mixture for
forward flights without affecting the hovering adjust-
ment. After the engine is started and warmed up, lift-
off into a hover and check that the engine is running
smooth with a good trail of smoke. If everything is fine,
open the throttle and enter forward flight. Take note of
the amount of smoke like we did in a hover adjust
ment. It is correct when you see a noticeable steady
smoke trail. Adjust the high-speed needle valve to
obtain slightly rich but consistent setting.
STOPPING THE ENGINE
1. Fully close the throttle barrel to stop the engine.
2. As soon as the engine stops running, be sure that a
fuel line clamp is used in Tube(B) to prevent fuel from
flowing into the engine.
3. On the final flight of the day, the fuel line clamp
should be used to stop the engine in order to prevent
rust and corrosion.
FUEL AND GLOW PLUG
We have found that the fuel and glow plugs listed below
will give the best engine performance.
Fuel
Powermaster 30% Special Heli Blend
Cool Power 30% Special Heli Blend
Glow Plug _ YS #2 Enya #3 OS #8
IMPORTANT!
Silicone rubber is used in many parts of the YS engine.
Use only glow fuel of methanol for cleaning. Gasoline
and other volatile solutions will damage silicone if used.
WARRANTY
Strict quality control is implemented by our factory in all
phases, from parts manufacturing to final assembly.
If performance deteriorates or a part fails due to a manu-
facturing error, YS engine will repair or replace the en-
gine at no charge in the period of one year from date of
purchase.
Warranty does not cover normal maintenance.
Should the engine be modified, incorrectly assembled or
abused, there will be a normal charge for parts and la-
bor.
Fig.1
Fig.2
B
A
High Speed 100%
Hover 40%
Low Speed 0%
44
42.3
17.5
37
Idling Needle
Fuel Filter ( Not included )
Tube (B)
Tube (A)
Check Valve
Tube (C) 35mm
High Needle
Hover Needle
36
STARTING SETTING / OPERATING SETTING
