Mastic Handgun
4
Part 1040769A
E
2004 Nordson Corporation
Valve Stem Adjustment
See Figure 3.
Use the following procedure to adjust the valve stem:
1. Relieve system and material pressures. Trigger the
gun to purge residual material.
2. Loosen the stem nut and spring housing.
3. Insert a 3 mm hex wrench into the hole in the spring
retainer screw and into the spring housing.
4. Turn the spring housing and stem nut to change the
trigger travel and the size of the valve opening.
Tighten the stem nut to the torque specification listed
on Figure 4.
5. Using a screwdriver, turn the spring retainer screw as
needed to close the valve stem.
6. If material continues to flow after releasing the trigger,
replace the valve stem and seal. Refer to the Repair
section for the procedure.
SPRING
HOUSING
VALVE
SPRING
STEM
NUT
RETAINER
SCREW
Figure 3 Valve Stem Adjustment
Spring Tension Adjustment
1. Relieve system and material pressures. Trigger the
gun to purge residual material. Disconnect the
material hose from the gun.
See Figure 3.
2. Using a screwdriver, turn the spring retainer screw as
needed to close the valve stem.
Troubleshooting
These procedures cover only the most common
problems that you may encounter. If you cannot solve
the problem with the information given here, contact your
local Nordson representative for help.
Problem
Possible
Cause
Corrective
Action
1. Material leaks
around nozzle
or nozzle nut
Dirty or
damaged
metal sealing
surfaces
Clean nozzle,
valve seat,
and stem.
Replace parts
if necessary.
Valve or
spring tension
needs to be
adjusted
Adjust the
valve or spring
tension.
2. Gun responds
slowly
Valve or
spring tension
needs to be
adjusted
Adjust the
valve or spring
tension.
