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 back plate assembly. Notice the impression
mark or dot opposite the rod journal on the crankshaft.
2. This mark is to point straight down or lined up with the outer case seam
line at the bottom and hold crankshaft securely.
3. Reinstall the cam with the dot facing you. After you fully installing cam
and then check dot should be pointing straight down will give you right
timing.
Operation of YS Super Mount (Option)
1. It is hold by 4 screws, 2 on the front ring and 2 on the rear soft mount.
There are two different height of spacer we provide.
A set spacer (MN110S) : 10mm thickness
B set spacer (MN111S) : 4mm thickness
2. Please be sure not to hit any part of the fuselage by the engine after it
installed.
3. If damper oil is leaked, refill TAMIYA damper silicon oil #600. Damper is a
consumption parts, please exchange if you fined worn or some defect.
Cleaning
This engine is using silicon gaskets, “O” rings etc. Please use methanol or
model engine fuel for cleaning. Do not use Kerosene, Gasoline, Machine
oil, Automobile parts cleaner or house hold lubricants to clean. It will harm
silicon parts.
Engine Cooling
Be sure to secure cooling air for engine cooling. If it is not enough cool-
ing air for the engine causes heat up the regulator and carburetor to make
vaporized or percolates the fuel and will get deteriorations of engine perfor-
mance or stop the engine. Please read carefully below for provision.
1. Please open air intakes and outlets as big as possible.
2. Take off cowling when you make long engine adjustment included idle
adjustment. When air temperature is high, it may heat ups the regulator
and carburetor to make vaporized or percolate the fuel even with out cowl
ing. If it happens, wait till engine well cooling down before you restart and
adjust.
Rusting provision
Do not leave fuel in the engine after you finished for day. If you store the en-
gine long period of time, few drops (about 1cc) of model engine lubricant oil
from carburetor and clank several times. Do not use Automobile engine oil.
They will not mix together with alcohol.
Parts and Repair Service
If you can not find repair parts form hobby shops, you can order parts direct
to our factory. We also do repair your engine at our factory. If you need
repair service, please make detailed of states and send together with the
engine.
Warranty
We strictly inspect each process of production from parts to final assemble
for keep good quality. If a performance deteriorates or part fails due to a
manufacturing error under normal usage will repair no charge with in 1 year
starting from the date of purchase. Warranty will not cover normal wear.
Even with in 1 year warranty term, improper disassemble or assemble, un-
der improper usage, any modification will avoid this warranty and there will
be normal charge for parts and labors.
57
136.5
14
119.4
68.6
149.5
63
25
58
114
Air
Tube B
Fuel Clunk Tank
Regulator
Front Nut
Rear Nut
Front Ring
Rear Mount
Battery（4.8~8.4V）
Switch
Red
Black
Ignition Box
Brown Red Yellow
Black
Red Black
Plug Cap Screw
* Please tap lightly with a small hammer,
as the spark plug cap is tight fit to the
spark plug.
Tube Ａ
Safety Instructions
In order for you to use of the engine, please read through this instruction
manual carefully. This instruction manual uses special words, if you have
any difficulties for understanding, please ask the hobby shop you purchased
or contact us directory.
1. Mount the propeller must use propeller nut supply with the engine.
2. Select a good quality propeller and follow instruction by manufactures.
3. Select a propeller size not increases practical rpm in the air.
4. Be sure not people standing front and sides of propeller while running.
5. Use electric starter to start the engine with idle position of the carburetor.
6. After start the engine, move behind of propeller and well adjust needle
setting before you fly.
7. It becomes extreme high temperature while and after engine runs. Do
not touch engine, exhaust header, muffler, and any parts attached to the
engine while engine runs or before cool it down.
8. Ignition system develops extreme high voltage so please careful when
you operate. It is very dangerous to modify the ignition systems by your
self.
9. Sparking noise may cause shorten the range of receiver. Please range
check with motor running on the ground before you fly. If there are range
problem, DON’T FLY!
10. If engine runs not correctly, DON’T FLY!
11. Do not use this engine other than radio controlled airplanes. Can not
use for radio controlled helicopters.
12. You have full responsibility while you operate the engine. Please be ex
tra care for safety when never you operate the engine.
Installation
Connect the engine to the tank and CDI wiring as shown in “Fig.1” Battery
and switch for CDI unit is not supplied of the engine set. Soft mount and fuel
filter are option.
1. The recommended fuel tank size is 500cc to 700cc (18 to 24 oz). A stan
dard clunk type fuel tank may be used. If this type of tank is used, you
must use the special clunk supplied with the engine. Please note that with
this clunk, all of the fuel cannot be used from the tank. As soon as any part
of the clunk becomes exposed, the engine will stop due to air entering the
fuel pump.
2. Always use a fuel filter. We recommend YS filter (6720). With this filter,
you must remove the cloth portion of the filter and leave both the metal
filter screens in place.
3. Because of this pomp system, fuel level of the tank will not influence of
engine runs, you can place fuel tank near C.G. position.
4. Please consider avoid cutting ignition wires by vibration when you do wir
ing. Use plastic “spiral wrap” supplied the engine set to wrap the shielded
plug wire.
5. Please place receiver and ignition box about 15cm apart. Some of the ra
dio needs to be apart them over 30cm to avoid radio interference. Wrap
the ignition box in form rubber or other vibration absorbing material, same
manner of receiver, and fasten. Do not use bracket holes on the box for
fasten directory to the airplane.
Fuel
1. Use a good quality alcohol based model engine fuel containing 5% to
25% nitro, and oil content 5% to 25%. You can not use gasoline fuel.
2. When you filling the tank, disconnects Fuel Tube “A”, or Fuel Tube “B”
see “Fig.1” from connecting tube to filling. If you use “T” nipple on the fuel
line to filling, use fuel stopper on the Fuel Tube “A” see “Fig.1” to avoid fuel
in to the engine.
Propeller
1. Due to the high output power of the DZ185CDI engine, it is supplied with
a double locknut system for added safety. Mount the propeller and tighten
the rear nut. Next, tighten the front nut. The rear nut has an offset shoul
der so the front nut will secure itself to the rear nut.
2. Please retighten propeller nut periodically.
3. Select a propeller that will allow the engine to run at maximum speed be
tween 6,000 to 8,000 rpm range.
4. We recommend sizes 20x10.5, 20.5x10, 21X10. Other prop sizes may be
used as long as the correct rpm range.
High Speed Needle Valve Adjustment
1. An electric starter is mandatory for starting this engine.
2. When the needle valve is turned clockwise, the mixture is leaner. When
it is turned counter-clockwise, the mixture is richer. A good starting posi
tion for the high speed needle valve is 2 turns open from the fully closed
position.
3. Check ignition switch off first and turn the engine by electric starter with
full open throttle to get fuel from tank to carburetor.
4. Close the carburetor to the idle position, turn on ignition switch and start
the engine by electric starter. Warm up the engine with little higher than
idle rpm.
5. Brake-in the engine one or two tanks of fuel on the ground with good rich
mixture setting before you adjust for best high speed needle position.
6. To achieve best high speed needle valve position by gradually turn nee
dle valve clock wise till rpm drops with fully opened throttle. The position
right before rpm becoming drops is the peek position ( highest RPM ).
Then the needle valve should be opened approximately 1/4 turns from
highest RPM.
Brake-in
1. Starting the engine with high speed needle valve 2 turns open from the
fully closed position and idle position on carburetor.
2. After start the engine, increases rpm gradually by operates throttle control
up and down. Do not suddenly open throttle to fully open position.
3. If mixture is too rich and miss firing, turn clockwise high speed needle
valve to leaner mixture.
4. Brake-in the engine one or two tanks (600cc or 20oz. tank) of fuel on the
ground with richest possible mixture setting.
Battery for CDI Unit
Use 4.8~8.4V Ni-Cd ,Ni-MH or Li-Po batteries capacity around 700mAh.
You can get over 5 (five) 10 minutes flights.
Idling adjustment
1. To get 1,200rpm to 2,000rpm idling.
2. When the regulator is turned counter-clockwise, the idle mixture is leaner.
When the regulator is turned clockwise, the idle mixture is richer. Adjust
regulator by turn 45 degree at a time.
3. If idle mixture is too rich, gradually rpm drops and stops after continuous
idling. If engine stops when you change attitude of airplane on the ground
also too rich on idle mixture. If mixture is too lean on idle, rpm is go up
and down and not keep stable when you make continuous idle.
Spark Plug
Use spark plug supply with the engine. Plug gap is 0.30mm (0.013”) to
0.45mm (0.018”). If plug gap become over 0.5mm (0.020”) will cause miss
firing the engine. If gap becomes over 0.45mm, tap the element by hammer
to adjust the gap of the plug.
Tappets Adjustment
1. Tappet clearance is preset at the factory.
2. Clearance adjustment may need after first one hour running time due to
initial wear. After first adjustment, clearance should be checked as normal
maintenance for every 10 hours running for maintain maximum perfor
mance.
3. Clearance adjustment should be done when the engine is cool.
4. The proper clearance should be set at 0mm (0.000”) to 0.1mm (0.004”).
The adjustment is achieved by loosening the lock nut see “Fig.2” and turn-
ing the adjustment screw see “Fig.2”. The engine must be at top dead
center on the compression stroke before any adjustments are made. This
engine runs best with the valves set at a tight setting. If the valves are set
too loose, power will be affected.
FIG 1
Fig2
DZ185cdi
Bore
35mm
Stroke
31.8mm
Weight
965g
（
Engine, Plug
）
100g
（
Ignition Box
）
Displacement 30.6cc
Practical rpm 1,000~9,000rpm
OPERATOR'S MANUAL
Tappet Clearance
