User Manual

GS R/C

DLA ENGINE OPERATING-INSTRUCTION

MANUAL

08/20/2014 Copyrighted Material

Page - 38 DLA 32, 58, 64, 116, 116-I2 & 128cc Rev. A.05.01

CARBURETOR TUNING and CARE:

A tachometer is required for initial carburetor tuning and is a good idea for subsequent tuning.

Remember to never adjust the carburetor while the engine is running.

The carburetor’s high and low mixture valves have been preset at the factory; however, different

altitudes and climates may require minor adjustments. Turning the mixture adjustment-screws

clockwise, leans the mixture and turning the screws counter-clockwise richens the mixture. If

you get completely out tune, reset the mixture controls as follows:

1. High Adjust: Turn the Needle Valve Screw clockwise until it stops, then counter-

clockwise 1-1/2 to 1-3/4 turns.

2. Low Adjust: Turn the Needle Valve Screw clockwise until it stops, then start at 1-turn

counter-clockwise and advance to 1-1/4 (in 1/16 turns) as needed to start engine.

IMPORTANT: When turning either mixture adjustments clockwise to the stop point, take care

not to over tighten and destroy the value seat. A “TWO-FINGER” hold on the screw driver

provides a light touch and a reasonable feel for the stop point.

Adjust the High Mixture: (Clockwise leans the mix and increases the rpm. Counter-clockwise

richens the mix and generally decreases the rpm.)

1. Start the engine and measure the rpm.

2. Adjust the High mixture to achieve maximum rpm (engine stopped).

3. Turn High mixture counter-clockwise (richen) until the rpm drops to 100 to 2o0 rpm less

than the maximum rpm.

4. Return to idle, and idle for approximately sixty (60) seconds.

a. Be sure the idle rpm is constant and smooth.

b. If the idle is too rich, the rpm may slow until the engine stops.

i. Adjust accordingly.

5. Check the Low to High throttle transition, by somewhat rapidly moving the transmitters

throttle control from idle to maximum.

a. See “Trouble Shooting” if the transition is not smooth and responsive.

Adjusting the Mechanical “Idle” Screw:

1. The Mechanical Idle Adjustment Screw is simply a mechanical advancement or decrement

of the carburetor’s butterfly throttle.

2. Adjust to the Mechanical Adjustment Screw to the lowest idle that keeps the engine

running and does not cause any aircraft forward motion at idle rpm.

3. If you plan to stop the engine by completely closing the butterfly-throttle, then you will

need to remove the Mechanical Idle Adjustment Screw or back it out far enough to allow

the butterfly to completely close. Do not attempt to remove the spring that returns the

butterfly value to the low position.

NOTE: On the 116cc-I2 and the 128cc QUAD richen the high-needle on the rear cylinder/bank

carburetor by about 1/16 to 3/32 turns to help cool these cylinders, if they are running too hot; or

event more so, in the event of a particularly hot flying day.