Applications And Basics Of Testing - Mityvac MV4529 Manuel D'utilisation

applications & Basics of testing
The MV4529 Cooling System Pressure Tester is designed to
diagnose and pinpoint the presence of leaks in an automotive
cooling system. It contains equipment to manually pressurize
and monitor a cooling system. Leaks are indicated by a drop
in pressure over a few seconds or minutes. The location of
external leak(s) is pinpointed by the visible seepage of fluid
resulting from the pressure. Internal leaks, which may not be
visible, typically indicate a blown head gasket or damaged
block or head, and can be diagnosed by monitoring the
pressure during a quick "engine on" test.
The MV4529 can also be used to test cooling system pressure
caps, which utilize a relief valve for protection against over-
pressurization. A malfunctioning cap can cause over- or under-
pressurization of the cooling system, leading to overheating and/
or severe engine damage. This test is performed using the pres-
sure pump included in this kit, however it also requires cap test
adapters that are not included with this kit, and must be
purchased separately. Refer to the Adapter Selection Guide
included in the kit for more information on cap adapters.
precautions
This equipment is designed for servicing a variety of vehicles
in a safe, convenient manner. However, differences in cooling
systems may make it impossible to perform some of the tests
indicated in these instructions on every vehicle. The procedures
documented in this manual are to serve as guidelines for the use
of this equipment. In addition to these guidelines, always follow
the manufacturer's recommended procedures when
servicing each unique vehicle. Do not attempt to force a test
on a cooling system for which this equipment is not designed
to perform.
Performing cooling system tests using the MV4529 is simple and
straightforward if you follow the instructions. However, always
keep in mind that you are working with a system that may be full
of cold or hot fluid that is under pressure and just waiting to be
expelled. If you are testing an engine that is hot and/or pressur-
ized, always stop to think before pressing the relief valve, remov-
ing a cap, or disconnecting a hose or other component.
Always read carefully and understand instructions prior to using
this equipment.
Always wear eye protection when removing radiator or coolant
bottle cap, or when performing any cooling system test.
Never remove the radiator or coolant bottle cap, or attempt to
pressurize the cooling system of a vehicle that is overheated.
Always allow system to cool prior to attempting to perform any
cooling system related test procedure.
Page Number - 4
Basics of testing
When deciding where to connect to the cooling system,
first look for the radiator and determine if it has a fill neck
and pressure cap. This is common on about half of US
manufactured vehicles, and almost all Asian manufactured
vehicles, and would be the first choice for connecting. If the
radiator is closed and inaccessible, then the connection will
be made through a coolant bottle. Some automotive cooling sys-
tems utilize a coolant overflow bottle that is not part of the sealed
system. Attempting to test the cooling system through this bottle
will not connect you into the sealed system, and will simply vent
the test pressure to the atmosphere. This type of overflow bottle
is easily recognized because it typically utilizes
a snap-on style cap or a threaded cap that is open to atmo-
sphere. There are no adapters that are designed to fit this type
of coolant overflow bottle. A test connection should be made
through a radiator or coolant bottle with a bayonet or threaded
style of cap designed to maintain a specific pressure in the
cooling system.
adapters
MV4529 includes one (1) bayonet style cooling system adapter
that fits most early and some late model US manufactures cars
and light trucks. This or an alternative adapter is required to
connect the test equipment to the cooling system of the specific
make and model being tested. Additional adapters are avail-
able separately for other US, Asian and European manufactured
vehicles. Refer to the Adapter Selection Guide included in this
kit for a list of applications for all system and cap adapters avail-
able from MityVac. Once the correct adapter is identified for the
vehicle being serviced, it can be used to perform all of the tests
outlined in this manual.
Form 823094