How to Properly Install Propeller Screws

How to Properly Install Propeller Screws

How to Properly Install Propeller Screws

--Important Notes on Using Gear-Drive Propeller Hubs

Improper installation of pre-drilled propellers on the engine hub may result in engine damage or propeller failure, posing significant risks.

To install propeller screws properly:

1: Ensure Proper Drilling

For propeller drilling, it is crucial to confirm the correct dimensions and hole diameters beforehand. The drilling must be perfectly perpendicular to the propeller mounting surface. If you lack a suitable jig for drilling the purchased propeller, you can contact the seller or distributor for assistance.

2: Secure the Propeller

Most engine hubs are designed to accommodate screws of varying lengths. Simply use the screws and washers to tightly secure the propeller hub washer and the propeller onto the hub. When installing the screws, start by loosely tightening two diagonal screws. Once all screws are in place, proceed to fully tighten them.

Special Attention for Engines with Electric Starters

Engines equipped with electric starters differ from standard hubs when installing screws. For example, when using the EPHIL Pro version engine, incorrect installation or using screws of improper lengths can damage the gear-drive propeller hub assembly, rendering the engine inoperable.

Examples of Improper Installation

Case 1:

Mr. A installed his 20*8 wooden propeller onto a 38cc Pro engine hub using only four screws and the propeller washer. Based on his past experience, he omitted the flat washers and spring washers. After tightening the four screws, he found the engine shaft seized up and became difficult to rotate, making it impossible to start the engine.

Case 2:

Mr. B brought his aircraft to a field to test his newly installed 40cc T Pro engine, only to discover he had lost several hub screws. He borrowed four screws from a DLE40 engine to install the propeller onto the hub. However, he found that the engine shaft locked up, and even the electric starter could not rotate the shaft.

Why This Happens

To balance weight, safety, and structural integrity, EPHIL engines feature a compact design for the gear-drive propeller hub assembly. This design necessitates particular attention during screw installation.

Critical Installation Instructions:

1: Always install the flat washers and spring washers on all four screws, as shown in the pictures below. Omitting these components can cause the screws to move the internal parts of the gear-drive propeller hub assembly, leading to a locked shaft.

 

 

2: Choosing the Correct Screws

For Pro versions equipped with electric starters, the screw specifications differ from other models. Using the correct specifications is essential when replacing screws. The table below provides the screw specifications for propeller installation on EPHIL Pro engines with electric starters:

By following these instructions and ensuring the correct hardware is used, you can avoid some potential issues and safety hazards, and ensure smooth operation of your engine and propeller.