A blockage in the mixing vessel of screed pumps will become evident when the pressure builds up on the pressure gauge and the screed pipe stops moving. Here are a few tips on how to locate and clear the blockage in the mixing vessel.
- The easy way to locate the blockage is to walk upon the screed line. If the screed pipe is soft at the outlet of the vessel, we know it is a blockage in the mixing vessel.
- Next, disengage the sending switch and release all the compressed air with the air relief valve.
- Move on to switch the machine off and disengage the blades.
- Disconnect the screed pipe at the outlet location.
- Check the screed pipe for a blockage. If clear, it is obvious the blockage is in the outlet within the vessel.
- Remove the safety grill to access the mixing vessel.
- Dig away the screed to gain access down to the outlet from the inside. An obstruction may now be found. Use a narrow bar and place it in the outlet from the inside. Push the obstruction back into the cleared mixing vessel and remove.
- Connect the safety grill back into place.
- Reconnect the pipe and safety pin.
- Switch the engine on, close the relief valve, engage the blades and switch the send button.
- Monitor the pressure gauge to confirm delivery.