YS-FZ120

YS-FZ120
OPERATOR’S MANUAL
FZ120 Supercharged
BREAK-IN
fig.3
To maximum engine performance and increase durability, please follow
this break-in procedure.
fig.1
58
63
Bore
Stroke
Diaplacement
weight
Practical rpm
Tappet Clearance
1. Use the same size (or slightly smaller) propeller than you intend to
use in flying.
SPECIFICATIONS
30.4mm
27.5mm
19.96cc
880g
2,000 -12,500rpm
25
2. Use a good quality fuel which contain 15-30% nitromethane and an
oil content of Low Viscosity oil 20-24% oil. Synthetic or castor oil can
be used, or a combination of both.
DO NOT USE FOUR CYCLE FUEL DUE TO LOW OIL CONTENT.
3. After the engine has started, slowly bring the throttle up to full.
Set high speed needle so it is running at a good rich setting without
the glow driver. Run engine at this setting for approximately 20
minutes with the throttle moving from low to high speed.
4. After the initial 20 minute break-in, mount the engine in the aircraft
and set the high speed to a richer than normal setting for the first 10
flights. This will help to lubricate all moving parts.
YS Fuel Filters
TAPPET ADJUSTMENT
Tappet clearance is preset at the factory. Adjustment if needed should be
checked after the initial break-in. For maximum performance, valves should
be checked as normal maintenance.
Check Valve
HIGH SPEED NEEDLE ADJUSTMENT
Tube(A)
108.5
1. Adjustment of the high speed is done by the carburetor needle valve.
When the needle valve is turned clockwise, the mixture is leaner. When
it is turned counterclockwise, the mixture is richer. A good starting
position for the high speed needle valve is 2 1/2 turns open from the
fully close position.
Tube(B)
2. When the engine is started, open the throttle gradually. Next, find the
peak position (highest RPM) by adjusting the needle valve. Then the
needle valve should be opened approximately 1/8-1/4 turns from
full RPM to achieve best performance. The engine may stop if the
throttle is opened to full immediately after starting. Wait until the
engine has warning up and pressure has developed in the tank.
YS Fuel Filters
128
LOW SPEED ADJUSTMENT
This engine is equipped with a new low speed needle valve to adjust the
mixture from low to mid throttle. See fig.1 for location.
FEATURES
PROPELLER INSTALLATION
The FZ120 was designed for the pattern competiton, scale and large sports
models. As aircraft increases in size, so does the need for power.
With a few modifications internally, YS was able to generate more power
in the same 120 case. The YS 4 cycles are so unique, almost every square
inch is used in some way to produce power.
Due to the high torque of the 120 engine, we have equipped it with
a double locknut system for safety.
1. Factory starting position is 1 1/2 turns open from the fully closed
position. The low speed needle should be set after the high speed
needle has been adjusted.
1. Mount the propeller and tighten the rear nut. Next, tighten the front nut
as shown in fig.2. The rear nut has a offset shoulder so the front nut
will secure itself to the rear nut.
2. Close the throttle gradually to an idle (approximately 2,000rpm). Let it
idle for 15-20 seconds and then slowly advance the throttle.
The adjustment is set when low to high speed has a smooth transition.
2. Select a good quality propeller that will allow the engine to run at
maximum speed between 8,000 to 9,000rpm range. We recommend
sizes 14x12~14,15x10~12, 16x8~10 .
3. If the engine is running rough at idle or to rich, turn the low speed
needle counterclockwise to lean out the low end.
* Supercharged
* Fuel Injected
* Regulated and Pressurized Fuel System
* High and Low Speed Adjustments
GLOW PLUG
4. If the engine speeds up at idle , the low speed mixture is to lean.
Turn the low speed needle clockwise to richen the mixture.
fig.2
5. If the engine is to lean on the low end, it can detonate and stop when
transition from low to high RPM.
Front Nut
Rear Nut
START UP
1. Connect the engine to the tank as shown in fig.1.Since high pressure
is applied to the tank, tighten all connections carefully. Care must be
taken to prevent pressure leakage due to undertightening of the check
valve or by kinking the fuel lines.
2. Always use a fuel filter. We recommend YS filter.
3. Match the direction of the check valve arrow in fig.1, with the arrow
facing towards the tank.
2. The proper clearance should be set 0.04-0.1mm or 0.002-0.004 in.
The adjustment is achieved by losing the locknut (fig.3) and turning
the adjustment screw. The engine must be at top dead center on the
compression stroke before any adjustment are made.
CAM GEAR TIMING
If for some reason you have to disassemble your engine, please follow
these important steps on reassembling the cam gear.
1. Remove the carburetor and backplate assembly. Notice the
impression mark or dot opposite the rod journal on the crankshaft. This
mark is to point straight down or lined up with the outer case seam line at
the bottom.
2. Reinstall the cam with the dot facing you and is pointing slightly to the
left. This will allow the cam to turn to the right when properly installed.
The dot should be pointing starting up when cam is fully installed.
Reinstall cam cover and timing is now set.
DIAPHRAGM AND CHECK VALVE DISASSEMBLY
Diaphragm;
1. Remove the regulator assembly by removing the two allen head screws.
2. Disassemble the regulator and clean with alcohol or appropriate cleaner.
Select the most appropriate glow plug from those designed specifically for
4 cycle engines. Glow plug selection greatly affects the maximum engine
output and low idle. If RPM’s decrease or stop when the booster cord is
removed, replace the plug. We recommend the OS Type F plug for
maximum performance.
INSTALLATION
1. Clearance adjustment should be done when the engine is cool.
1. Remove tube A from the check valve, (CAUTION) Tank pressure must
be release first before tube B is opened. Remove tube B and begin to
fill fuel tank.
2. Open the high speed needle 2 1/2 turns from the closed position.
3. Open the throttle fully and slowly turn the propeller 10 times. This will
prime the engine and pressurized the fuel tank.
4. Close the throttle to the idle position and connect the glow driver.
The engine is now ready for starting.
DO NOT ATTEMPT TO START ENGINE AT FULL THROTTLE, AS THIS
IS VERY DANGEROUS. ALWAYS USE EXTREME CAUTION WHEN
ENGINE IS RUNNING.
REGULATOR ADJUSTMENT
The regulator is preset at the factory. The top of the brass adjusting screw
is flush with the top of the regulator housing. Turning the regulator screw
will not change the pressure the engine develops. The adjustment screw
is used to adjust the amount of fuel to the carburetor. Turning the screw in
will decrease the amount of fuel and turning the screw out will increase
the amount of fuel to the carburetor.
3. When reinstalling the regulator, use a new gasket and note that the
small casting tab on the regulator goes towards the propeller.
Check Valve;
1. Open the check valve by rotating the body counterclockwise.
Note the small clear silicone disc. DO NOT LOSE.
2. Clean and reassemble. Check to make sure air will only past though
the check valve one way.
IMPORTANT! Silicone rubber is used in the YS engine. Only use glow
fuel or methanol for cleaning. Gasoline and other volatile solutions will
damage the silicone if used. Do not use petroleum based oils as after run
lubricants.
FZ120 Parts LIST
# Part#
1
F1801
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
F1202S
F1202
F1203
F1204
F1205
F1806A
F1806
F1407
F1408
F1409
F1410
F1411
F1212
F1213
F1214
F1215
F1216
F1217
F1218
F1919
F1520
F1421
F1222
F1323
F1224
F1225
F1826A
F1826
F1427
F1492
F1429
F1230
F1232
F1233
F1234
F1535
F1236
F1237
F1238
F1239
F1240
F9122
F1341
F1242
F1243
F1244A
F1244
F1245
F1246
F1247
F1248
F1249
F1250
F1251
F1752A
F1752
F1753
F9156
F9157
F1545S
F1545
F1546
F1555
F1556
F1557
F1483
R6124
F1258
F1259
F1260S
F1463
F1564
F1565
F1268
F1269
F1382
F1266
Description
Crankcase
Head Cover Set
Head Cover
Head Cover Gasket
Valve Cover Screw Set
Head Gasket
Head Assembly
Cylinder Head
Intake Valve
Exhaust valve
Valve Spring Set
Spring Retainer Set
Valve Spring Retainer Clips
Rocker Arm Set
Tappet Adjusting Screw Set
Tappet Adjusting Rock Nuts
Rocker Arm Shaft
Rocker Arm Shaft Screw
E Ring Set
Head Screws
Crankshaft
Cylinder Liner
Piston
Wrist Piston
Wrist Pin Retainer Set
Piston Ring
Connecting Rod
Back Plate Assembly
Back Plate
Disc valve
Rear Disc Valve Retainer
Retainer Screw
Back Plate Gasket
Cam Gear Cover
Cam Gear Cover O-Ring
Cam Gear Cover Screw
Cam gear
Cam Followers Set
Push Rod Set
Push Rod Cover Set
Push Rod Cover O-Ring
Front Bearing
Front Bearing Oil Seal
Rear Bearing
Cam Gear Bearing Set
Fuel Nipples Set With Washers
Regulator Assembly
Regulator Body
Regulator Adjusting Screw
Regulator Adjusting Screw O-Ring
Diaphragm
Regulator Plunger
Plunger Spring
Regulator Gasket
Regulator Screw Set
Carburetor Assenbly
Carburetor Body
Throttle Barrel
Low Speed Needle Valve
Low Speed Needle Valve O-Ring
Needle Valve Assembly
High Speed Needle Valve
High Speed Needle Valve O-Ring
High Speed Needle Valve Seat
Needle Valve Socket O-Ring Set
Needle Valve Detent
Throttle Barrel Seal
Throttle Barrel Retainer
Throttle Stop Screw
Throttle Stop Spring
Throttle Arm Set
Carburetor Gasket
Drive Washer
Drive Washer Retainer
Intake Pipe
Intake Pipe O-Ring
Wrist Pin Access Plug
Propeller Washer
QTY
1
4
1
1
2
1
2
72
1
1
1
2
2
4
2
2
2
1
1
2
5
1
1
1
1
2
1
1
71
3
18
11
10
9
14
16
67
17
55
72
65
15
63
12
6
66
57
56
13
7
31
8
64
39
31
61
5
60
62
1
1
1
1
6
1
1
2
1
2
2
2
4
1
1
1
2
6
24
37
54
23
59
44
23
22
31
21
58
68
29
38
28
25
39
26
36
30
27
34
32
20
33
43
73
19
35
43
1
1
1
1
1
1
1
2
1
41
40
70
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
4
1
1
42
44
44
69
74
75
51
48
49
45
52
49
50
#
Part#
75
F1267
Description
Propeller Nut Set
QTY
2
F1473S
F1574S
F1497S
F1497
F1971
F1498
Gasket Set
O-Ring Set
Muffler Assembly
Muffler
Rock Nut
Exhaust Pipe
4
14
1
1
1
WARRANTY
Strict quality control is implemented by our factory in all phases, from parts
manufactiring to final assembly. If performance deteriorates or a part fails with-in
one year of purchase due to a manufacturing error,YS will repair or replace the
engine at no charge. Warranty will not cover normal wear.
Should the engine be modified or incorrectly assembled, there will be a normal
charge for parts and labor. The use of four cycle fuel due to low oil content will also
void warranty.
47
46
YAMADA MFG.CO.,LTD
67 Tsuchitori Inuyama Aichi 484-0917 JAPAN
TEL: 0568 67 0265 FAX: 0568 67 7801
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertising