Graco DC12 Operation & Setup page 63

Troubleshooting
Troubleshooting Chart Cont.
Problem
Meter pressures not balanced
Meter outlet pressure too high,
metering inaccurate, decreased
flow rate, bad mix
Off Ratio
63
Cause
Improper operation of supply pumps
Inadequate material supply to metering
pumps
Curing material in the mixer or dispense
block.
Inadequate material supply to metering
pumps
Piston cups are damaged or worn
Air in the material
Solution
Check for proper operation
of material supply pumps.
Verify Supply pump
pressure is reloading
metering pump. Perform
ratio check procedure.
Verify supply pump
pressures. Perform ratio
check procedure.
Perform Ratio check
procedure. Verify pump
works bypassing mixer.
Remove mixer and clean.
Remove outlet dispense
block and clean.
Verify supply pump
pressures. Perform ratio
check procedure.
Check for leakage. Rebuild
pump assembly
Perform priming procedure
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