User's Manual

Troubleshooting
22 312753E
Hydraulic leak around
Cleanout Plunger Proximity
Switch
Damaged o-ring Replace o-ring See page 12
Proximity Switch not tight-
ened down onto Adjusting
plug
Tighten Proximity Switch
against Adjusting Plug to
compress seal
See page 12
Hydraulic leak out of sens-
ing area of Material
Plunger
Improper sealing Replace with Polypak seal
and modify Sensor Cap
Contact Graco
Chemical leak out of Noz-
zle Grip Assembly
Loose Hex o-ring Seat Replace o-ring See Maintenance, page 9.
Damaged o-ring Seat Replace o-ring(s) See Maintenance, page 9.
Cleanout Plunger falls out Fractured Cleanout
Plunger
Send in MixHead for repair
Excessive amount of foam
in hydraulics
Worn Scraper Seal Send in MixHead for repair
Badly scored or galled
Cleanout Plunger
Send in MixHead for repair
Chemical pressure rise
during pour- one side only
Incorrect orifice size of
Injection Nozzle
Replace with proper orifice
size(s)
See page 10
Partial blockage in orifice
of Injection Nozzle
Remove blockage See page 10
Partial blockage in Nozzle
Grip
Remove blockage See page 10
Incorrect Injection Noz-
zle/Adjustment Stem size
combination
Use matching Nozzle and
Stem sizes
See Technical Data,
page 31
Chemical pressure rise
during pour- both sides
Cleanout Plunger partially
blocking impingement
chamber
Adjust Cleanout Plunger
stroke to clear impinge-
ment chamber
See page 17
Runner and/or Aftermixer
too small
Enlarge Runner and/or
Aftermixer
Chemical pressure drop
during pour- one or both
sides
Restriction exists in return
loop from MixHead to Tank
Remove restriction in
return loop
Injection Nozzle stuck in
body
Exposure to air has hard-
ened chemical remaining
around Injection Nozzle
Remove Injection Nozzle
using nozzle ejector tool
See page 10
Mounting Holes stripped
out of body
Incorrect mounting of Mix-
Head
Send in MixHead for repair
Chemical or hydraulic leak
around fitting
Damaged o-ring Replace o-ring
Damaged fitting Replace fitting
Erosion of Adjustment
Stem Tip and Orifice of
Injection Nozzle
Chemical attack of steel
parts or wear by abrasive
Replace with Carbide
Adjustment Stems and
Injection Nozzles
See page 10, and Techni-
cal Data on page 31
Poor quality foam at lower
output
Incorrect Orifice size of
Injection Nozzle
Replace with smaller Ori-
fice size
See page 24
Approaching lower limit of
MixHead throughput
Adjust stroke of Cleanout
Plunger
See page 24
Symptom Probable Cause(s) Corrective Actions Reference