Graco Therm-O-Flow Plus, Instructions Manual

Page: 53 / 82

53 309085
Heated Pump Troubleshooting
For additional information about the Check-Mate 800 Displacement Pump, see Form 308570.
Problem Cause(s) Solution(s)
Rapid down stroke or up stroke
(pump cavitation) Material not heated to proper
pumping temperature. Check and adjust temperature set point.
Wait for pump/plate to heat up.
Air is trapped in pump. Bleed air from the pump using this pro-
cedure:
1. Place a waste container under the
pump bleed port.
2. Turn on air to the pump
3. Allow material to flow from the bleed
port until it is air-free.
4. Shut off air to the pump and close
the bleed port.
5. Turn air on to the pump and set the
pump air regulator for normal opera-
tion.
Downstroke: Lower check in
pump is worn or fouled.
Upstroke: Upper check in pump is
worn or fouled.
Clean, rebuild or replace pump, as nec-
essary.
Material leaks around pump outlet Outlet fitting is loose. Tighten outlet fitting.
Material leaks around bleed port Bleed port fitting is loose. Tighten bleed port fitting.
Pump won’t move up or down Problem with air motor. See Air Motor Troubleshooting chart on
page 54.
Foreign object lodged in pump. Remove object and rebuild pump
assembly.
WARNING
To reduce the risk of serious injury
whenever you are instructed to relieve
pressure, always follow the
Pressure
Relief Procedure (page 23).
Before attempting to dislodge a foreign
object:
1. Relieve system pressure.
2. Remove the pump from the air
motor.
Wet-cup leaks Worn throat seal. Replace wet-cup and throat seal pick-
ings (See form 314934).