Applications and
basics of testing
MV4534 cooling system pressure tester is
designed to diagnose and pinpoint presence
of leaks in automotive cooling system. It
contains equipment to manually pressurize
and monitor cooling system. Leaks are
indicated by drop in pressure over a few
seconds or minutes. Location of external
leak(s) is pinpointed by visible seepage of
fluid resulting from pressure. Internal leaks,
that may not be visible, typically indicate a
blown head gasket or damaged block or
head, and can be diagnosed by monitoring
pressure during quick “engine on” test.
Precautions
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 tests
indicated in instructions on every vehicle.
Procedures documented are to serve as
guidelines for use of equipment. In addition
to guidelines, always follow manufacturer’s
recommended procedures when servicing
each unique vehicle.
• Do not attempt to force test on cooling
system equipment is not designed for.
• Always keep in mind that system may be
full of cold or hot fluid that is under pres-
sure and waiting to be expelled. If testing
engine that is hot and/or pressurized,
always stop to think before pressing relief
valve, removing cap, or disconnecting hose
or other component.
• Always read carefully and understand
instructions prior to using this equipment.
• Always wear eye protection when remov-
ing radiator or coolant bottle cap, or when
performing any cooling system test.
• Never remove radiator or coolant bottle
cap, or attempt to pressurize cooling sys-
tem of vehicle that is overheated.
• Always allow system to cool prior to
attempting to perform any cooling system
related test procedure.
• Strap attachment is recommended to
secure radiator adapter to reservoir and
prevent from dislodging.
Basics of testing
When deciding where to connect to cooling
system, first look for 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 radiator is closed and
inaccessible, connection will be made
through coolant bottle.
Some automotive cooling systems utilize
coolant overflow bottle that is not part of
sealed system. Attempting to test cooling
system through bottle will not connect into
sealed system, but will simply vent test
pressure to atmosphere.
This type of overflow bottle is easily
recognized because it utilizes snap-on style
cap or threaded cap that is open to
atmosphere. There are no adapters designed
to fit this type of coolant overflow bottle.
Test connection should be made through
radiator or coolant bottle with bayonet or
threaded style of cap designed to maintain
specific pressure in cooling system.
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