Assembly Troubleshooting While assembling a pump, problems may arise, below are common issues that may arise during assembly. Expeller ring/stuffing box jamming on shaft sleeve: Weight causing it to sag on shaft. Back liner will not bolt up tight to adapter: Fouling on expeller. Expeller ring/stuffing box not fully engaged between adapter and back liner: Stuffing box seal missing or incorrectly positioned. Impeller jams before locking up to expeller/shaft sleeve: D Fouling on back liner. Impeller does not have equal gap, top and bottom, to back liner: 10 Bearing assembly is out of alignment. Shaft sleeve or sleeve spacer does not turn with shaft. Interference between shaft shoulder and sleeve, expeller or impeller. Casing will not bolt up tight to adapter: Wear ring fouling on impeller. 4