INTRODUCTION
Congratulations on your purchase of a Thunder Tiger model
engine. ALL the latest Thunder Tiger series engines have been
designed to combine the high performance with easy handing
and maintenance using modern CAD computer technology. Major
components of the engines are machined from the highest quality
materials using state-of-the art CNC manufacturing techniques,
resulting in consistently high quality and reliability.
The PRO series helicopter ring type engines are equipped with
dual ball-bearings, Schnuerle porting, one ring type piston/cylinder
assembly and two-needles automatic mixture control carburetor.
IMPORTANT
This engine will provide you with years of safe use, provided
that you carefully follow these safety instructions:
1. This model engine IS NOT A TOY, but a powerful miniature
engine that is capable of inflicting damage to both people and
property if misused.
2. Always mount the engine securely in a test stand or high-quality
engine mount. Never, never attempt to clamp your engine in
a vise!
3. Make sure that you use the suitable size engines and rotors
for your helicopter that followed the recommend of helicopter
instruction manual.
4. Make sure that the installation of the clutch/cooling fan system
on the engine is securely fastened and correctly. Unsuitable
installation will cause huge vibration during helicopter flying.
5. Do not run your engine around dirt, sand or loose gravel. Such
material can be thrown into your eyes by the propeller. In
addition, the engine can be damaged by these materials entering
the carburetor.
6. Take care to keep all loose clothing, rags, tools, etc. away from
the rotors.
7. Take care when handling your engine after running. Model engines
get very hot during operation!
8. Always operate your engine with proper ventilation. Model
engines produce toxic fumes when run in a closed room or
confined area.
SPECIFICATIONS
INSTALLATION
Engine
Mount your engine
securely to rigid engine
mount. Make sure the
mounting surface are
absolutely flat and
parallel to avoid engine
distortion (bearings,
crankcase...) and power
loss.
Dimensions
NECESSITIES
The following items are necessary for operating the engine, these
are available at you hobby dealer.
FUEL
A good quality, commercially available fuel containing 25% lubricant
and 75% methanol is recommended for break-in /run-in and
general usage. We also recommend castor oil or a castor /synthetic
blend only for use as a lubricant. Fuel containing 5%~30%
nitromethane and 20% lubricant is for use when more power is
required. Most fuels containing synthetic lubricants (only) are
much less tolerant of a lean run compared to fuel that contains
castor oil. If availability or local conditions force you to use a fuel
that contains only synthetic lubricant, we suggest that you keep
your needle valve set to a slightly richer setting, allowing more
lubricant to flow through your engine to extend engine life and
maintain optimum reliability. Do not use fuel containing less than
20% lubricant.
CAUTION 1
Methanol and nitromethane are poisonous and highly flammable.
Keep out of reach from small children and keep away from heat
and open flame.
CAUTION 2
Excessive heat can greatly reduce the life of your engine. Most
of the heat generated by combustion is removed via the lubricants
that are contained in your fuel, and exits the engine as exhaust
vapor. As a precaution, you should periodically remove the muffler
from your engine and visually inspect the exhaust port and piston.
If the outer surface of the piston is stained a very dark color, it
can indicate that your engine may be overheating. This can be
caused by either an excessively lean needle setting or a lack of
airflow across the cylinder and head.
THUNDER TIGER PRO.H
RING TYPE SERIES ENGINES
INSTRUCTIONS
GLOW PLUG
The type and quality of glow plug used in your engine will have
a major impact on overall performance and reliability. The engine
operates best with a R/C long-type plug such as Thunder Tiger,
K&B, or O.S.No.8. Fox plugs (while of excellent quality) have a
colder heat range and may cause idle or throttle transition problems
in small engines.
BREAK-IN/RUN-IN
Because Thunder Tiger engines are precision-made from quality
materials and is a ringed engine, prolonged break-in is not required.
But, when it is new, the engine must be run in a rich condition
for at least 6 tanks of fuel to allow for proper break-in. It is important
to make sure the engine does not overheat at anytime. Also, it
is critical that the engine be run in an area free from excessive
dirt and sand.
CARBURETOR ADJUSTMENT
The Thunder Tiger PRO.H type carburetors are specially designed
for the high performance Thunder Tiger PRO series helicopter
engines and provide the proper air-fuel mixture automatically for
helicopter flying at any throttle operating range.
Since the carburetor has been pre-set at the factory, large
adjustments of this carburetor should not be required. However,
under different operating conditions, minor re-adjustments may
be required. These conditions include set-up of the helicopter,
glow plug used, and weather conditions.
IMPORTANT
Before trying to adjust the carburetor, please note the following.
In helicopters, engine failure in flight as a serious problem,
especially for the inexperienced modeler. It can mean loss of
control and a resulting crash.
For ensuring safe and reliable control on the helicopter flight, it
is a must that the engine keeps running and that the throttle has
quick and reliable response. Therefore, the carburetor adjustment
is very important for the helicopter and this should be done with
great care to obtain an optimum throttle response. In the helicopter
flight, the throttle response on the medium speed range with the
partial throttle opening is very important. Because, medium speed
range is widely used in the flight . On this carburetor, only two
adjustable controls are provided.
l) Needle Valve (installed in left hand side of carburetor) This
controls the mixture strength of the engine speed range from
half to fully opened throttle.
2) Mixture Metering Screw (hidden in the throttle barrel in right
hand side).This controls the mixture strength of the speed range
from idling to half opened throttle.
Please note the best mixture strength around half opened throttle
is obtained with the balanced controls of both l)Needle Valve and
2)Mixture Metering Screw.
SETTING BEFORE ENGINE STARTING
Close (turn clockwise) the Needle Valve until it stops. Open the
Needle Valve 3 turns from the closed position.
Make sure that the throttle linkage is set so that the throttle rotor
is fully open when the transmitter throttle stick is moved to full
high speed position and that the throttle rotor is fully closed when
both the throttle stick and throttle trim lever are moved to the
lowest position .
ADJUSTMENT
Following procedures are recommended to adjust the carburetor.
Adjustment low speed performance (range from idle to 1/3 opened
throttle)
1) Start the engine with the transmitter throttle stick fully down
and the throttle trim level set the neutral position.
2) Set the throttle trim lever so that the engine runs with highest
idling rpm but without engaging the clutch.
3) Increase the engine speed by advancing the transmitter throttle
stick gradually until the helicopter just lifts up(floats) from the
ground. Warm up the engine by keeping above floating condition
for approximately 10 seconds then slowly reduce the engine
speed, land, and allow the engine to idle for a while.
4) Repeat above procedure several times. If the engine tends to
hesitate or stop after hesitation, the mixture at idle is not correct.
Generally speaking, if the mixture at the idle is too rich, the
engine stops abruptly with short hesitation when the throttle is
opened. On the other hand, if the mixture is too lean, the engine
will hesitate a little longer with weakened exhaust sound.
5) If the engine runs with hesitation but does not stop then try to
increase the engine speed by means of the transmitter. Try to
hover the helicopter, maintaining the altitude of approx. l ft or
30 cm from the ground, then carefully watch the exhaust smoke.
If the mixture is too rich, you may observe an excess of exhaust
smoke and will feel lazy throttle response. If the mixture is too
lean, the engine runs with higher pitched exhaust sound, without
any or very low exhaust smoke then the speed will be reduced
showing overheating tendency and the helicopter is hard to
continue hovering.
6) After you find the condition of the mixture, turn the Mixture
Metering Screw 30 degree at a time, according to the mixture,
by using a small screw driver to correct the mixture. If it is too
rich, turn the screw clockwise. If it is too lean, turn the screw
counter-clockwise.
Adjustment high speed performance
The optimum Needle Valve setting is usually 1/4~l/2 turn closed
from the starting position (i.e 3 turns open from the fully closed
position). It depends, of course, on l) the individual characteristics
of the helicopter and its engine/muffler installation, 2) the fuel used
and 3) atmospheric conditions.
The Needle Valve should be gradually closed until the highest
performance is obtained in flight at full power.
However, take care not to close the Needle Valve to a too lean
setting and risk overheating the engine, in the pursuit of maximum
performance.
Adjustment middle range performance
As previously stated, in helicopter flight, throttle response at
medium (hovering) speeds is most important. If the Mixture Metering
Screw (low speed) and Needle Valve (high speed) are properly
balanced, the mixture will be correct, through the medium speed
range.
If, however, minor re-adjustments prove to be necessary for the
best possible throttle response, proceed as indicated by the
following symptoms and required corrective action:
1) If the mixture at middle range is lean, gradually increased
engine speed is accompanied by diminished exhaust smoke
and a high-pitched exhaust sound if hovering is prolonged. In
extreme cases, the engine will overheat and lose speed, so that
hovering cannot be maintained. In this event, open the Needle
Valve l5 to 30 degrees and turn the Mixture Metering Screw
30 t0 45 degrees counter-clockwise.
2)If the mixture at middle range is too rich, positive and quick
throttle response will not be obtained, the exhaust smoke will
be dense and the exhaust sound will be lower, probably
accompanied by fuselage vibration. In this even, close the
Needle Valve 30 to 60 degrees and turn the Mixture Metering
Screw 45 to 90 degrees clockwise.
Note: It is most important to make the Needle Valve adjustment
in small increments of not more than 15 to 30 degrees and the
Mixture Metering Screw adjustment not more than 30 to 45
degrees as advised, when seeking optimum middle range throttle
response. Excessive re-adjustment will upset either low speed
performance or high speed performance. Carry out re-
adjustments patiently until the best balance of idling, hovering
and high speed performance is achieved and the engine responds
quickly and positively to the throttle control. Throttle response
at hovering speeds is also affected by the relationship of the
main rotor pitch angle to throttle opening. If the optimum middle
range, throttle response cannot be obtained by the carburetor
adjustments described above, try adjusting the helicopter's pitch
control characteristics.
ENGINE CARE
Always keep the outside of your engine clean. Use clean, fresh
fuel and keep your fuel can, pump, and fueling system free from
dirt particles. Install a fresh fuel filter between the fuel tank and
carburetor, and between your fuel pump and filling line to prevent
any potential of dirt entering your engine. Model fuel contains
alcohol, which is hydroscopic (meaning that it attracts moisture
from the atmosphere). This can cause corrosion to the internal
engine parts. After each flying session, run all the fuel out from
inside the engine and disconnect the fuel line from the carburetor.
Put 4 or 5 drops of after-run oil (Marvel Mystery Oil, Prather,
Pacer, etc.) into the carburetor and turn the propeller over by hand
several times to protect the engine bearings and internal parts
from corrosion. The use of after-run oil is also important during
periods of prolonged storage (such as winter). We suggest removing
the engine from the model, and liberally applying oil into the
carburetor and glow plug hole, wrap your engine in a soft cloth
and store in a sealed plastic bag.
Do not dismantle your engine unnecessarily, as this may upset
precision fits. If it is necessary to clean your engine completely
(such as after a crash), remove only the needle valve assembly
and ventri carburetor, muffler, backplate, and cylinder head. Flush
the entire engine with fresh fuel and reassemble.
On the piston/ring set, there is a small pin in the piston ring groove
to fit the ring. If you have to dismantle the piston/ring from the
engine, you must take care the position of the pin. When you re-
install the piston, you should follow the original setting. Incorrect
installation of the piston/ring will cause serious damage of the
engine.Apply after-run oil to the engine and store or re-install into
the model. Do not dissemble your engine further than described
above, or your warranty may be voided!
INSTALLATION OF THE PISTON
There is a point mark on the piston top surface.
When you reassemble the engine, this mark
should be toward the front of the engine as
you install the piston. If the direction is not correct,
the piston ring would be stuck with the ports
on cylinder.
WARRANTY
Your engine is guaranteed to be free from defects in materials
and workmanship for a period of 3 years from the date of purchase
when returned for service accompanied by proof of purchase
(register receipt, credit card invoice, etc.). Crash damage or
problems caused by improper use are specifically not covered
under this warranty. Damage caused by customer disassembly,
use of improper or substandard fuel, use of improper accessories
(such as propellers, glow plugs, etc.) or any use of the product
other than its specific intended use will automatically void this
warranty.
SERVICE PROCEDURES
Should your Thunder Tiger engine require service, please follow
the following guidelines:
1. Do not return the engine to the place of purchase, as they are
notauthorized or equipped to perform service.
2. Remove the engine from the model. We cannot accept
equipment for service other than the engine.
3. Along with your engine and proof of purchase, enclose a
complete written explanation detailing the problem(s) with your
engine. Be sure to include your name, address and daytime
telephone number.
4. For repairs not covered under warranty, the charges will be
billed to you C.O.D. Please mention if you wish to have an
estimate of non-warranty repair charges prior to us beginning
service. (This may cause a slight delay in your repair.)
5. For customers outside of the U.S. and Canada, contact the
authorized Thunder Tiger agent in your country.
6. For U.S. and Canadian customers, send your engine via
insured mail or U.P.S. to ACE HOBBY DISTRIBUTORS INC.,
2055 Main Street, Irvine, CA 92614
ENGINE
A (mm/in)
B (mm/in)
C (mm/in)
D (mm/in)
E (mm/in)
F (mm/in)
G (mm/in)
H (mm/in)
PRO-39H(R)
74.5/2.93
53.0/2.09
76.8/3.02
61.0/2.40
15.0/0.59
38.0/1.49
31.0/1.22
43.4/1.709
PRO-50H(R)
84.9 / 3.343
60.3 / 2.374
86.4 / 3.402
69.1 / 2.72
17.5 / 0.689
44 / 1.732
34.0/1.34
45.61.795
PRO-70H(R)
83.1 / 3.272
55.5 / 2.185
101.9 / 4.012
80.1 / 3.154
25 / 0.984
52 / 2.047
43.0/1.69
56.6/2.228
PRO-90H(R)
83.1 / 3.272
55.5 / 2.185
102.3 / 4.028
80.5 / 3.169
25 / 0.984
52 / 2.047
43.0/1.69
56.6/2.228
JA0391.V9
ENGINE
ITEM Displacement Bore
Stroke
Crankshaft Practical
OUTPUT
Weight
NO
(c.c/cu.in)
(mm/in)
(mm/in)
Thread
RPM
(BHP/RPM) (g/oz)
PRO-39H(R) 9604 6.45 / 0.394
21.6 / 0.850 17.6/ 0.693 UNC 1/4-28 2,000~22,000 1.35/18,000 290/10.22
PRO-50H(R) 9605 8.27 / 0.504
22.5 / 0.886 20.8 / 0.819 UNC 1/4-28 2,000~20,000 1.75 / 17,000 405/14.28
PRO-70H(R) 9607 11.49 / 0.701 25 / 0.984
23.4 / 0.921 UNC5/16-24 2,000~18,000 2.25 / 16,000 570/20.10
PRO-90H(R) 9609 14.78 / 0.902 28 / 1.102
24 / 0.945
UNC5/16-24 2,000~16,000 2.75 / 15,000 575 /20.28
B
F
K
E
A
H
C
G
D
J
I
17
11
12
10c
10b
10a
8
9
7
15
16b
4
12
6
17
13
5
16a
12
2
1
PARTS LIST / CARB
THUNDER TIGER CORPORATION
http:// www.thundertiger.com
PRO-90H(R) / 9609 SHOWN
No. Description
9604
9605
9607
9609
PRO-39H(R)
PRO-50H(R) PRO-70H(R) PRO-90H(R)
1
PROP NUT
AA0025B
AA0025B
AML5/16B
AML5/16B
2
PROP WASHER
AA0026B
AA0026B
AA0280B
AA0280B
4
CRANKSHAFT
AA0792
AA0740
AA0910
AA0902
5
CRANKCASE
AN0969
AN0739
AN0911
AA0901
6
BACKPLATE
AA0224
AA0324
AA0909
AA0909
7
CONNECTING ROD
AN0964
AN0325
AN0285
AN0905
8
WRIST PIN ASSEMBLY
AA0337
AA0337
AA0917
AA0489
9
CIRCLIP
AA0327
AA0327
AA0287
AA0513
10a PISTON
AN0966
AN0273
AN0914
AN0906
10b PISTON RING
AA0967
AA0274
AA0916
AA0908
10c CYLINDER
AA0965
AA0272
AA0915
AA0907
11 CYLINDER HEAD
AA0968
AA0743
AA0912
AA0903
12 GASKET SET
PN0221
PN0192
PN0193
PN0194
13 CARB RETAINING BOLT
PN0220
AN0275
AN0781
AN0781
15 CARBURETOR ASSEMBLY
9204N
9239N
9294
9266
16a BALL BEARING, FRONT
AMV699Z
AMV1438Z
AMV1438Z
AMV1438Z
16b BALL BEARING, REAR
AMV6901
AMV6902
AMV16003
AMV16003
17 SCREW SET
PN0222
PN0116
PN0003
PN0003
DISCRIPTION OF PARTS
9204N
9239N
9294
9266
A CARBURETOR BODY
PN1263
PN1181
PN1200
PN1254
B CARB. ROTOR ASSY
PN1205
PN1205
PN1201
PN1255
C NEEDLE VALVE ONLY
PN1264
PN1173
PN1173
PN1173
D SPRAY BAR ASSEMBLY
PN1273
PN1273
PN1185
PN1185
E NEEDLE VALVE ASSY.
PN1274
PN1274
PN1186
PN1186
F THROTTLE LEVER
PN1102
PN1102
PN1102
PN1102
G BOLT&FUEL INLET
PN1007
PN1007
PN1007
PN1007
H RATECHET SPRING
AA1025B AA1025B AA1025B AA1025B
I O RING SET
PN1202
PN1202
PN1202
PN1202
J MIXTURE METERING SCREW SET PN1265
PN1206
PN1203
PN1203
K THROTTLE ROTOR SET
PN1266
PN1207
PN1204
PN1256