temperature gauge installation.
In 1984, Rotax
introduced the liquid cooled engine into it's aircraft
engine line, the 532 Rotax which was later updated to
the 582. Both the 532 and 582 uses a 50/50 mixture of Glycol (antifreeze) and
Note: While this is the
recommended mixture - for COLD climates - in warmer
climates or seasons - mixtures of 10% anti freeze to 90%
distilled water can be used. This will aid in lowering
coolant temperatures - anti-freeze is NOT an effective
coolant! It is used to prevent freezing and supply
lubrication to the system.
My experience has shown
that a mixture of 10% antifreeze can drop temperatures
as much as 30 degrees versus 50% - in some applications.
Do not use
tap water - garden hose water - or water from a water
The chemicals in water will cause corrosion
of the internal metal parts.
USE DISTILLED WATER!
The use of any water
other than distilled will cause deposits to form that can
prevent the transfer of
heat from the cylinder to the water jacket. Liquid
cooled engines like their air cooled counter parts
require temperature gauges to
monitor the temperature of the liquid in the cylinder
head and cooling system.
A water temperature gauge when properly installed and
located, can accurately measure the
temperature of the coolant, so as to prevent serious
internal problems, and help prevent over heating and or
Water temperature gauges use a thermistor - a
resistor that varies its resistance according to the
temperature of the liquid in the cooling system and engine.
The two styles of gauges that I am familiar with both
external power supply. This provides the necessary 6 to
12 volts required to operate the gauge.
temperature range should be between 140'F and 180'F
(60'C and 8O'C) with the maximum being 20O F (95'C). One
thing to note is that initially a high reading may start
going down due to a low coolant level, because the
fluid is escaping and thus is not reaching the
sending unit, (which should be located in the center of
the cylinder head) will then indicate a LOW temperature
While blockage in the
coolant flow or air flow system, will indicate a
install the water temperature gauge and sender, connect
the wire from pin #4 of the gauge to the ignition switch
or other 12V source. The wire from pin #5 is
grounded. Connect one of the wires
from the sender to the wire from pin #2
of the gauge. The other wire of the sender is grounded.
The sender has no polarity thus it does not matter
which sender wire is attached where.
Route all wires away from the hot manifold and
other pipes. Tie the wires to other wire bundles, if
they are available, and support the wires at 12" to
15' intervals. When going through to metal firewalls
etc. use rubber grommets to prevent the metal from tearing the