on Gasoline Engine

This page lists some of the most frequently asked questions.Please refer to following Q&A, whenever you have a question, such as"What is Gasoline Engine?" "Is my Engine broken?" etc.


What is the advantage of Gasoline Engine?


Good fuel efficiency.

A2 The fuel expenses are low.

You can easily find the fuel.


It does not pollute airframe.

A5 Hassle-free from Plug heat.

Exhaust gas is transparent and no stickiness.

A7 Exhaust gas temperature is high, so it is convenient for smoking.
A8 Bearing is Rust-proof.

You can use lacquer based paint.


What is the disadvantage of Gasoline Engine?

A1 You have to formulate the fuel by yourself.

Ingenuity is required to produce airframe, such as set up a baffle plate to increase cooling efficiency for high temperature of Engine.

A3 Output of Gasoline Engine is slightly lower than that of Glow one at the same displacement.
A4 As the range of air fuel ratio is narrow, its adjustment is slightly difficult.
A5 Carbon is easily accumulated on the inside of Engine.
A6 Use of resin based mount and floating mount is prohibited.


Is it difficult to handle gasoline engine?


As the handling of Gasoline engine is almost the same as Glow Engine,  it is not difficult once you get used.

Q4 Is it difficult for us to adjust gasoline engine?
A1 As the range of air fuel ratio is narrow, its adjustment is slightly lean compared to glow engine. As a guide, if it is possible with you to upright the airframe, allow it to reach the peak of main needle when airframe is upright.  As a guide at horizontal position, you can understand approx. position of the peak without uprighting the airframe if you remember how much turns you should when reaching
the peak once again at the horizontal position after reaching the peak at the first upright position.


Is it difficult to produce the airframe?


Ingenuity is required slightly to produce airframe, such as built firewall sturdily with standard equipment of aluminum mount, and set up cooling system with baffle plate. You must use the standard equipment of aluminum mount certainly for firewall.


What kind of fuel tank should we prepare?

A1 You can use the same fuel tank for glow engine.  However you have to use rubber Lid, pipe, and filter with spindle for gasoline only. 
( Besides, bind connecting part of
pipe firmly with metallic wire. ) And the capacity of tank is fuel consumption (described in the instruction manual) X flight hours + 100cc150cc is standard.   There is a possibility for the tank lack of sufficient capacity for flight hours that the Engine could be out of order when absorbing air through filter with spindle by liquid lever change.  Close the tank to Engine as close as possible and adjust the liquid level.  Gasoline Engine is equipped with a carburetor with pump, and the performance of the carburetor with pump is the same as that of muffler pressure.

Q7 What is the fuel mixture ratio?
A1 Gasoline : Oil = 20 : 1 is standard.  It is no problem to increase the mixture ratio of the oil in the initial break in and during summer time.   Regular gasoline is enough to use.


What kind of oil should we use?

A1 Use high quality 2 cycle oil. It is safe to choose oil hardly burned oil as our Engine is of Blow-by lubrication as well as glow engine. 
Our genuine oil is recommended.

Q9 What kind of battery should we use?
A1 NiCad, Nickel-hydrogen, Lipoic 2C that the voltage is 6V8V and capacity is more than1000mA.  We use NiCad 6V 1500mA for test running and it is enough energy to run for 1 hour at least.

Q10 What plug is used for the Gasoline Engine?

For FG-14C, 17, 21 Engines : Our genuine plug 乬SP-1乭 ( Plug Gap 0.40.5) .
For FG-30B, 36B, 40, 57T, 57TS, 84R3 Engines : NGK乬CM-1乭 ( Plug Gap 0.70.8).


What is the size of prop?


The prop is standard described in the article 乬Preparation Before Starting the Engine乭.  We use APC for models less than FG-30 at our test running.  We use carbon prop of Mejzlik for models more than FG-36.  Use prop which is strong and well balanced.   


What kind of possible causes are considered when engine is out of order?


Overheat due to production defects of cooling system.  

A2 Plug is deteriorating or defective plug gap.
A3 Advance failure of Ignition.
A4 Loosening of Plug cap.
A5 Accumulated carbon in combustion chamber and exhaust port.
A6 Accumulated carbon on the inside of muffler and the exit of muffler.
A7 If the carburetor is walbro, clogged filter could be possible cause.
A8 Deteriorating of firewall mounting the engine mount.
A9 Deteriorating of Battery.
A10 The oil does not fit the engine.
A11 Clogging of filter with spindle in tank.
A12 Percolation occurred due to over heat of Carburator.
A13 Foaming in the tank due to vibration.

Q13 What is the cause of breathing phenomenon in engine with walbro carburetor?
A1 Walbro carburetor belongs to float less type carburetor.  Air is easily stayed in Metering Chamber where the fuel of float less carburetor accumulates when engine started or percolation occurred, so air bleeding from Metering Chamber is necessary.Engine will stop at the worst if flying without air bleeding. Air bleeding is required forcibly in INVERTED and UPRIGHT. Side mounted one is automatically air bleeding during warming-up. 
The method of air-bleeding is as follows;

Make the opposite side of throttle lever face ground by laying down to left roll if inverted and laying down to right roll if upright at medium speed after a couple of times engine
racing in 1-2 minutes warming-up. The direction
If air is mixed, engine will suddenly stop. If engine does not stop during running, air-bleeding has completed.

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