Saito FG-11 User Manual

SAITO FG-11

4-Stroke Gasoline Single Engine Operating instructions

ThanksforbuyingSAITOFG-114-strokegas-engine exclusivelyformodelairplanes.

Inordertoavoidmisuse,pleasebesuretoreadwellthis instructionmanualcarefully.Ifthereshouldbeanydeficiency, inconvenience,etc.concerningthemanufacture,ourcompany willrepairthemwithresponsibility.

Anyfailureortroublecausedbyunnecessarydisassembly, modification,orotherusesthanthoseprovidedintheinstructionmanualisnotsubjecttothewarranty,however. Moreover,allresponsibilitiesfortheuseoftheengine,and otherobligationsandresponsibilitiesbasedonlaws,regulations,etc.arebornebythepurchaserandtheuser,andSAITO SEISAKUSHOCO.,LTD.isexemptfromanyresponsibilities.

FG-11 is one of the smallest gas-engine among 4-stroke gas-engines which is designed based on the long sellerGlow engine “FA-62”. Taking same devices such as carb, spark plug, ignition system from exsiting single-gas engines such like “FG-21” “FG-17” “FG-14C”, durability, stability, and reliability are given as well.

Notification about treatment of 4-stroke model gas-engine

Since valve timing is designed to get high power and high speed, the overlap range is relatively wide. So sometimes fuel get flown back from the carburetor. (It may spatter in the engine room.

Since the oil for lubrication is mixed in the fuel, waste oil from the breather nipple is dirty. Depending on treatment of waste oil, it can be spattered on the plane. Ref. Section 9

Since lubrication is through breather, sometimes the oil oozes from each joint or commissure however it’s no problem on performance.Depending on the quality of the oil, sometimes there can be rust inside the crankcase. But it’s no problem on performance as long

as there are no abnormal noise or backlash.

Specifications

	Bore		Ø27.0mm			19.0mm		10.9cc
				Stroke			Disp.
	Weight		Body: 465g / Mu er: 50g / Ignition system: 100g / Engine mount: 110g Approx.
	Practical speed		Approx.2,000-9,500rpm	Max on Gnd		Approx.8,500~8,800rpm
	Propeller		12”x8“~13”x8”	Static thrust		APC 13x7 Approx.1.3~1.7kgf (Depend on prop
	Fuel		Regular gasoline Oil 20:1 (Volume ratio)			Applications	4-stroke glow 50-60 class
Fuel consumption			Approx. 7cc/min (At full throttle 8,800rpm)
			*Fuel flow varies depends upon prop load. More fuel flow with larger load and less fuel flow with smaller load.
Battery for ignition system			Voltage:6-8.4V higher than 1,000mA is recommended
			Engine mount set	1set		Limit gauge (0.1t) for tappet adjustment			1pc
Standard accessories			Ignition system w/ sensor	1set		Spanner for tappet adjusting lock nut			1pc
			Spark plug [SAITO SP-1] Attached to engine 1pc			Hexagonal wrench set			1set
			Mu er set	1set		Plug wrench			1pc

1. Propeller

Depending on the airframe, please adopt the standard size in the data and use a reliable product which is generally on the market. (APC13 7 is recommended)

Please maintain sufficient balance. Since an imbalanced prop is vibratory and dangerous with

lowered performance, please maintain balance with a balancer. Moreover, a cracked prop is dangerous. Make sure to check any time and replace it with a new one if it’s cracked.

*Prop and fuel consumption

If the load is large (the diameter & pitch of the prop is large) for the engine characteristics, the air-fuel mixture should be rich. Thus the main needle has to be opened. That is, even if the revolution is low, the fuel consumption is high. Conversely, when the load is small and the revolution is high, the fuel consumption is lowered because the main needle can be closed.

In order to decrease the fuel consumption and prolong the engine life, a propeller should be used whose revolution is maximized when the throttle-valve is fully opened, while using an airframe which enables all flights with about 90% of the output of the propeller. In this case, the throttle valve will be further throttled during horizontal flight. On the contrary, an airframe which can only deliver performance in fully open condition will su er worsening fuel consumption and life.

-1-

Outside dimensions

Fig.1

2. Fuel

The fuel is mixture of commercial regular gasoline and reliable oil for 2-stroke. (Unleaded high-octane gasoline is not necessarily required for SAITO engine.)

[Example of oil]

Klotz KL-200 OriginalTechniplat eDeluxe Materials PowerModel 2T-S etc.

For the mixture ratio, please be sure to use “gasoline : oil =20 : 1” or richer by volume ratio. (ex. 1000ml of gasoline should be mixed with more than 50ml of oil ).

Any damage caused by the fuel used, in which the oil ratio is lower than 20:1 ratio, is not warranted.

Since gasoline is dangerous material, be careful of its storage, use, and transport enough. (The evaporative emission and exhaust smoke of gasoline have a harmful effect on a human body. Also, if gasoline is leaked, there is danger of fire etc.) Please note that we take no responsibility for accidents, health damages, etc which occur during storage, use and transport of gasoline.

3. Fuel Filterand fuel pump

Since commercial gasoline has many impurities, please be sure to use a reliable filter for the admission port of the gasoline-proof fuel pump (Fig.2), and in the fuel tank as well (Fig.3). Without using a filter, the performance of the carburetor is not delivered, resulting in failures.

Using optional part “Filter with weight” is highly recommended.

4. Fuel tank and piping

Gasoline-proof	Gasoline-proof tube
Pump	Option
Filter with weight
Option
Fig.2

			Fire wall	Air inhalation	Rubber cap for gasoline-resistant	above	Air inhalation pipe
				pipe	Fuel tank(100~150cc)	Fuel level
				Fuel feeding pipe
						Fuel level
				to Carb nipple
				Gasoline-proof tube			to Outside of
					Filter with weight
	Fig.3						the fuselage
		Engine center	Within 200mm (close as possible)		Center of fuel tank	Fig.4

For the capacity , refer to the data and select the best of commercial product. Please be sure to use a filter with weight. To avoid entrain any impurities to the carb, piping with “Fuel feeding pipe” and “Air inhalation pipe” (Fig.3) is recommended.

*Please be sure to use “gasoline-proof” products for the tank lid rubber, piping, and tubing. Some of the products for glow fuel can’t be used for gasoline. Please check carefully if there’re any crack on the piping, tubing, connection, and tank.

All of the connection parts should be bound by thin Nylon strap or wire to avoid fuel leakage or air induction to the fuel line. (If there are any leakages, the performance of the engine decreases dramatically.)

*The tank should be placed within the range of 200mm from the engine center to the tank center. When performing an acrobat with a large change in fuel level or that requiring an excessive movement of throttle, the tank must be placed at a position close to the engine as much as possible.

*When provide “Air inhalation pipe” as Fig.3, arranging the tube above the fuel level (Fig.4) is the effective way of fuel leakage prevention.

5. Spark plug

SAITO SP-1 spark plug is the standard equipment. Dimensions are as follows; Hexagon width: 8mm Screw size: UNEF 1/4-32

Reach (with a washer): 5.5mm Spark-gap: 0.4-0.5mm For replacement, please specify “SAITO SP-1”.

Since our four cycle engine uses a mixed gasoline, please decide the numbers of flights by yourself and clean the spark plug. Please replace when it is degraded. (Consider the plug as consumable).

6. Ignition system

*Be careful ofpossibility ofelectrical shock as it generates high voltage.

*The unit includes a plastic clip to hold the connectors and spiral tube to protect each wire.

The ignition system is designed to match SAITO 4-stroke gas-engines with automatic advancing system.

However this ignition system is designed to be an anti-noise product, please isolate it completely from the receiver, servo, and battery to avoid a radio-interference trouble. Moreover, it is desirable to utilize a noise filter (line filter). Especially, each switch (for Ignition and for Receiver) should be isolated and set far from each ones.

Caution:A gas-engine generates a noise which has an adverse effect on RC adjustment. Please be sure to carry out a noise check each time while the engine is running before flight. Since a noise which occurs during flight may lead to a large-scale accident, please carry out a noise check without fail. As a simple method, after starting engine you can check by removing the antenna of the transmitter and operate it about 50m away from the airplane. If there is no malfunction, it is normal.

-2-

The function ofeach cord;

(1)Plug cord (meshed high tension cord)

When you put on the plug cap, insert it to the plug until you can hear clicky sound to avoid coming off during flight. And then pull the plug cap to make sure that it won’t come off.

(2)Sensor cord (Black cord)

Connect with the cord from the sensor attached to the engine.

(3)Battery cord (Black/Red cord)

Please use the fully charged battery that has adequate spec (6-8.4V, more than 1000mA is recommended.). Between the battery and main unit, make sure to set an ignition switch whose capacity is higher than 3A.

(4)Tachometer cord (Brown/Red/Orange cord) Optional on-board tachometer can be attached.

Plug cap		Switch (not included)		Viewfrom front
(1)Plug cord		Capacity: More than 3A
	Main unit					Prop rotation
						(CCW)
	(3)Battery Cord
	(Red/Black)	Recommended battery
	(4)Tachometer cord
		5cell-NiMH
	(Brown/Red/Orange)	2cell-LiPo	CW			CCW
		Voltage:6-8.4V
Sensor		Capacity: More than 1,000mA		Advance	Delay
				Sparktiming	Sparktiming
	(2)Sensor cord					Handstart
	(Black)
Fig.5Ignitionsystem (G17-153)			Fig.6	NeutralPosition		easyarea

7. Sensorposition and Power/ Starting easiness

The ignition sensor can be moved to CW (advance the spark timing) or CCW (delay the timing) as Fig.6 shows.

At the factory default the sensor is fixed on the center (neutral) position. The reason is related to the methods of engine starting.With an electric starter-You can start wherever the sensor is fixed.

So you can set the sensor as the rpm reaches maximum speed.

By hand flip (Manual start)-Starting easiness depends on the sensor position.

The factory default is set as you can start by hand flip and also get highest rpm in that range as possible.

If you prefer easiness of hand starting, move the sensor to CCW direction to delay the spark timing. But then the maximum rpm will slightly decline.

If you prefer power (highest rpm), move the sensor to CW direction. But then you can't start by hand flip but only with starter. In addition by the feature of the ignition system, it heats up with engine running. When you restart the engine by hand flip, you should open the throttle valve slightly while it's hot. And it's better to enlarge the choke without wetting the plug.

For safety we recommend to use an electric starter.

8. Carburetor

A carburetor with a pump developed exclusively for our small-size four cycle gasoline engine is mounted, instead of using mu er pressure. Since the carburetor with a pump introduces the air from the air hole shown in the next figure, set it 2mm or more apart from the firewall or drill a hole on the firewall.

When adjusting the carburetor, refer to Fig.7.

Main needle:To adjust the speed at the time offull open ofthe throttle valve. Slow needle:To adjust the speed from the idling to the middle speed.

Turning each needle in clockwise direction, the fuel will become leaner and the rotation speed will increase. Turning it in counterclockwise direction, the fuel will become richer and the rotation speed will decrease.

Note:Thecarburetorforthegasolineengineistheassemblyofverystrictanddelicateparts.Sopleasemakesuretousefilteredgasoline. Moreover,DONOTdisassemblebyyourself.Ifthere’reanytroublesregardingcarb,pleaseconsulttheshopfromwhichyouboughttheengine.

Thread into about 5~5+4/5 turns (Approx.1.7~2.0mm from

the Reference plane)

Fig.7

Forthe reference The following data for the needle adjustment is iunder

the condition of APC13x7 prop and about 8800rpm.

The engine is installed in the inverted position.

Opening width of the needles vary depending on the atmosphere, prop, installing position etc.

Main needle:

4/5~1turn open from full close

Slow needle: 5~5+3/4 turn close

(1.7~2.0mm) from the surface of the throttle lever. Adjustment range tend to be narrow as displacement is smaller.

-3-