TST-019 MRTALPCH CHANNEL
– Rev. 2016-310
Page 9 of 20
19) If a leak existed when the valve with digital vacuum
switch, shown in
FIGURE 9
, was tested, there is no
convenient way to isolate the vacuum switch from the
valve.
In this case, since the digital vacuum switch is not
prone to leak, the likely cause is the solenoid or an
attached fitting. Check the fittings for any indication of
damage or cracks. If there is no indication of damaged
fittings, replace the solenoid.
20) For lifters using the analog vacuum switch:
The next test will require the ball valve to be set up to use on the 5/32" O.D. hose. As shown in
the following graphic.
21) Remove the ball valve from the
solenoid and cap off the 45°
barbed fitting, (
10A)
in
FIGURE 10
.
See inset for close-up view.
22) The vacuum switch is located
inside the control box.
Disconnect the 5/32" O.D. hose
(
10B
) from the control box (
10C
)
that connects to the solenoid
assembly. Note, this hose may
be blue or black.
23) Attach the end of the ball valve
with the vacuum gauge to the
hose removed from the control box that connects to the solenoid assembly. Using an
additional piece of hose, attach the other end of the ball valve to the control box. See
FIGURE 10
.
24) With the ball valve in the open position (handle in line with the valve), switch the power on
( )
, and activate the vacuum generating system by pressing the apply
( )
push button.
25) Close the ball valve (turn handle perpendicular to the valve) but leave the power on
( )
.
Note, both of the following conditions may exist; effect repairs as needed.
If the vacuum level of the ball valve’s vacuum gauge starts and continues to drop, the
indication is that the pump solenoid is the cause of the leak.
Examine the fittings attached to the solenoid assembly and, if there is no indication of
damaged fittings, replace the solenoid.
FIGURE 9
FIGURE 10
10C
C
10B
10A
