User Manual

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#3 - Testing Your Ignition Ground / Shielding
“Grounding” for the DL engines / ignition system is conducted through the Spark Plug / Spark Plug Cap (with Split
Ring Retainer installed) / Plug Cap Grounding Spring / Plug Wire Shielding / Ignition Module Case. If any part of
this circuit has been interrupted (worn, broken, torn, missing, etc.), an incomplete circuit can exist which might
cause radio interference.
The circuit can be tested with a Continuity Tester or Volt Ohm Meter, by attaching a test lead to the metal housing
of the ignition module (away from the clear label tape) and the other test lead to the engine. The tester must show a
completed circuit for it to be considered OK. If this circuit is incomplete, it should be repaired or replaced; a bypass
grounding circuit will not provide the required shielding.
NOTE: this test is not intended to be used in place of a complete (engine off and running) range check of your radio
system. A range check should be performed at the beginning of every flying day, or before any flight if you suspect
there may be a problem. Also, a careful visual inspection of the plug wire shielding should be performed at the
beginning of every flying day as a worn or frayed shield can allow interference to occur even if the grounding circuit
is complete.
EASY CHOKE SETUP
Here's an easy, inexpensive and lightweight way to set up a manual choke lever for your DL engine.
Attach a leftover servo arm to the engine mount bolt and run a servo control rod through it to the choke arm. Attach
the control rod to the arm with a ball link or nylon link so as not to create radio interference.
COWL VENT / COOLING OPENINGS
As a general rule, you need to have 3 times as much air outlet area as you have inlet area, for proper engine
cooling. We recommend that you open the front of your cowl enough to expose all the cylinder cooling fins to
incoming air. Cooling might also be improved by blocking some of the stock cowl vent area or by constructing
baffles to direct incoming air to the cooling fins.
FUEL FILTERS and FUELERS
While inline fuel filters are beneficial to long engine life, they can also be detrimental if too restrictive. Some fuel
filters are too restrictive for proper fuel flow even when they are new. If you use a filter between the tank and
carburetor, make sure it has a large enough capacity for proper fuel flow.
The TY1 (2025) Fuel Filter is suitable for this job,
having a “sintered bronze” element
that is not affected by petrol and is easily cleaned.
The TY1 (1161) Hand Fuel pump is also suitable
for Petrol as well as Glow Fuels, with no electric
motor it is safe to use with petrol.
Fuelers that have spring operated seals can malfunction enough to cause an air leak that will affect proper running
of your engine. Fuelers that have no moving parts such as fuel dots are less prone to air leaks and thus more
reliable.
What's the torque spec on the spark plug?
7 to 8 ft-lbs.
Running in procedure
The main thing to avoid with any new engine is excessive heat. It can cause damage very quickly to any engine. To
avoid this it is important to keep the mixture RICH. The extra fuel keeps the engine running cooler. Start by running
the engine in the model on the ground for 2 or 3 tanks of fuel. This ensures that the engine will run consistently and
reliably and avoids any dead stick landings while the mixture is set rich. When happy that the engine will not stop,