ML6984, ML7984 SERIES 4000 DIRECT COUPLED VALVE ACTUATORS
95C-10939—11
4
Weather-proof conduit fittings approved for out-
door and wet locations must be used to maintain
NEMA 3R rating.
3.
Remove stem button (Fig. 3) from valve stem.
4.
(Optional) Snap red position indicator (metal clip)
over valve stem and position for best visibility (Fig. 3).
Indicator will self-align to the marking on yoke after
complete operating cycle. It is recommended that
this is done after actuator installation.
Fig. 3. Preparation for Valve Assembly.
Assembly of MLx984 Actuator to the
Valve
1.
The drive shaft of the MLx984 Actuator has a 1/4-28
UNF threaded hole to link with the valve stem. Slide
the yoke over the valve bonnet (Fig. 4).
2.
Thread the MLx984 Actuator drive shaft onto the
valve stem all the way, until it is completely attached
(with no threads showing), by turning the valve actu-
ator in a clockwise direction, as viewed from above.
Depending on the valve body, use a pin or wrench to
keep the valve stem from turning. Note that the valve
actuator is shipped with the drive shaft in the mid-
position.
3.
Care should be exercised when using tools on the
valve stem during tightening (Fig. 4). DO NOT dam-
age the threads or other parts of the stem.
4.
Orient the conduit hole to the most desirable direc-
tion, then tighten the LOCKNUTS on the U-bolt.
5.
Remove the plastic cover from the MLx984 by loos-
ening the two captive screws located on the top. Drop
the Allen (Hex) type of set screw (included in the plas-
tic bag) into the top of the shaft, hex side up.
6.
Tighten the set screw to lock valve stem in place (Fig.
6), using a 1/8 in. Allen wrench (included).
Fig. 4. U-bolt Assembly.
NOTE:
Use the U-bolt supplied with the actuator. Do not
replace with stainless steel U-bolt on chilled water
valves. Condensation may cause corrosion of yoke
with SS U-bolt.
Fig. 5. Assembly of MLx984A to Valve.
Fig. 6. Locking MLx984A Drive Shaft to Valve Stem.
CAUTION
For proper valve operation the valve stem must be
threaded into the actuator all the way (with no
threads showing) and locked in place with the set
screw provided.
M25487
Valve Stem
Remove Stem Button
NOTE: DO NOT
DAMAGE ANY
PART OF
THE STEM.
Yoke
Position
Indicator
(Metal clip)
Valve Stem
ASSEMBLY OF POSITION INDICATOR
1
1 Position indicator will fit 1/4 in. - 7-1/16 in. valves.
M25488
M25489
Yoke
U-bolt
Valve Bonnet
DO NOT
1
2
1
2
THREAD ACTUATOR SHAFT TO VALVE STEM BY
ROTATING IN A CLOCKWISE DIRECTION.
TIGHTEN U-BOLT NUTS TO SECURE LINKAGE TO
VALVE BODY.
ADJUST
M25490
Valve Stem
5mm [3/16 in.] Slotted Screwdriver
or Allen Wrench
Linkage
Set Screw
