DLE 35RA - User Manual

DLE35RA
Users Manual
SAFETY NOTICE
This engine is not toy. For your own safety, please read the manual carefully before oper-
aon. Never allow children under the age of 18 to operate this engine without supervi-
sion. You are responsible for the safe operaon of this engine.
Before every use, check the engine assembly, propeller and airframe carefully for loose
screws and nuts. Locte 242 Blue (or similar) is strongly recommended on all the screws.

Summary

SAFETY NOTICE

ENGINE MOUNTING

ENGINE ADJUSTMENT

Low Speed Mixture Adjustment

Adjusts low speed needle for smooth idle and throttle transition. Checks for lean/rich symptoms.

High Speed Mixture Adjustment

Adjusts mid/high RPM mixture for optimal performance and altitude. Checks for lean/rich symptoms.

GENERAL ENGINE OPERATION

Warranty Information

Details engine warranty coverage, required proof, and proper usage.

Engine Damage & Warranty Exclusions

Lists specific actions that will damage the engine and void the warranty.

Contact Details

Overview

1. Function Description
2. Usage Features
3. Maintenance Features

This document serves as the user manual for the DLE35RA engine, a device designed for model aircraft. It emphasizes safety, proper operation, and maintenance to ensure optimal performance and longevity.

Function Description

The DLE35RA is an internal combustion engine primarily intended for powering model aircraft. It operates by burning a mixture of gasoline and oil, generating rotational power to drive a propeller. The engine's design incorporates an electronic ignition system to ensure reliable starting and consistent running. It is capable of producing significant thrust, making it suitable for various model aircraft applications. The engine's performance is influenced by factors such as altitude and atmospheric pressure, requiring careful adjustment to achieve peak efficiency.

Usage Features

Safety First: The manual strongly advises users that the engine is not a toy and should never be operated by children under 18 without supervision. Users are responsible for safe operation. Before each use, a thorough check of the engine assembly, propeller, and airframe for loose screws and nuts is mandatory. The use of Loctite 242 Blue (or similar) is highly recommended for all screws to prevent loosening due to vibration. During operation, it is crucial to always stand clear of and behind the propeller. No one, including the operator, should ever be in front of or to the sides of the propeller when starting or running the engine. Protective eyewear is essential for anyone near the engine, and loose clothing should be avoided to prevent entanglement with the propeller.

Engine Mounting: For the break-in process, the engine must be installed in an environment that can absorb vibration, such as within the model aircraft itself, or with a soft mount if bench running. Hard mounting to a bench without adequate vibration damping can cause damage to internal parts and shorten the engine's life. Mounting the engine in the model is considered the best method for break-in.

Fuel and Oil: The engine requires non-Ethanol 92 or 95 Octane fuel. For general use, a 30:1 oil ratio is recommended. While a 40:1 ratio may be used after the engine has been run in for 2 to 3 hours, especially with high-quality fully synthetic oil, a 30:1 ratio is recommended for prolonged life. It is crucial not to mix different types or brands of engine oil, as this can lead to carburetor fouling. For the break-in period, a 30:1 full synthetic oil ratio is specifically recommended.

Starting and Breaking-in: To start the engine, users should adjust the idle mixture (low speed mixture screw) if necessary. The engine should be idled until it warms up, then the RPM should be slowly increased. During the first tank of fuel, users should avoid running at full throttle. Instead, the engine should be run in short bursts of 1 or 2 seconds at up to 4500 RPM, then throttled back to mid-throttle, and finally to idle. This process should continue for 2 hours, gradually increasing the upper RPM and the duration of high RPM. If the engine's RPM sags at high RPM, the throttle should be immediately reduced. The engine should then be stopped, and the high-speed mixture screw adjusted 1/8 of a turn out before restarting and retesting.

Engine Adjustment: The carburetor mixture settings are crucial for optimal performance and need to be adjusted based on altitude and barometric pressures. A general starting point for adjustment is 1.25 turns out for the low-speed needle and 1.5 turns out for the high-speed needle.

• Low Speed Adjustment: This adjustment aims for a smooth idle and a reliable transition to high throttle. If the engine dies when advancing the throttle, the mixture is likely too lean. If the engine stumbles, the mixture is likely too rich.
• High Speed Adjustment: This adjusts the mid and high RPM mixture setting. The best practice is to set the high-speed needle to achieve maximum RPM, then open it an additional 1/8 of a turn to account for altitude. If the engine slows or stops at full throttle, the high-speed mixture is most likely too lean, requiring the high-speed screw to be opened 1/8 to 1/4 of a turn.

Important Caution: Running an overly rich mixture will lead to poor engine performance (stopping or spluttering during acceleration or deceleration), premature carbon buildup, a fouled spark plug, and excessive exhaust residue. However, running a lean mixture is even more damaging, as it can harm the cylinder and piston, and is not covered under warranty.

Maintenance Features

Spark Plug Check: During the break-in period and after a few runs at full throttle, it is recommended to unscrew and check the spark plug. A slight yellow color on the spark plug indicates that the mixture has been set properly.

Fuel Line Inspection: The fuel line should be periodically checked for possible pinholes or air leaks, especially if the engine's running becomes erratic.

Carburetor Fuel Screen Cleaning: The carburetor fuel screen requires periodic cleaning. To do this, carefully remove the pump cover (located on the inlet side of the carburetor), the gasket, and the pump membrane. The screen will then be visible and can be cleaned.

Warranty Information: All DLE engines come with a one-year parts and labor warranty. This warranty is valid when the engine is run according to factory instructions, with specified propellers, and using correct lubricants and lubricant ratios. The engine number and purchase date are recorded for warranty purposes, and users should retain their purchase invoice as additional proof.

Actions Not Covered by Warranty: Several uses are explicitly stated as damaging to the engine and will void the warranty:

• Running the engine without oil or with too little oil.
• Running the engine with an incorrectly sized propeller. Oversized propellers can increase stress and wear on internal components, leading to poorer torque and thrust. Undersized propellers can cause excessively high RPM and over-stress the engine.
• Running the engine without adequate cooling. This can cause overheat damage. It is essential to ensure the engine has adequate ducting to force air over the cylinder cooling fins. A minimum 1:3 cooling air inlet to outlet ratio is recommended, with additional venturi fins on the air outlet assisting in drawing air. Simply mounting an engine in the engine cowl without proper ducting is considered inadequate cooling.

DLE 35RA Specifications