That means your non-return ball-check valve
is leaking, or the barrel is worn so much that plastic is flowing backward over the slip ring during injection.
A bulb on the handle dispenses solvent through the hollow-center carbon rod and out to the swivel tip, locked with a ball-check valve
so there's no dripping.
If paint won't come out of the prime tube, the problem may be a clogged screen or filter, or a stuck ball-check valve in the pump assembly.
Most spray problems are a result of clogged filters, a clogged tip (below), or a pump that's either leaking at the packing or has stuck ball-check valves. Careful cleaning and proper maintenance will prevent most of these troubles.
The two significant findings were that the direct-clutch spring pack and piston have slightly different assembly steps from the other clutches because the piston has a ball-check valve inserted.
The first decision deals with whether a ball-check valve needs to be inserted in the cylinder.
At station 3A, the RF tag is checked for the clutch model type; if required, a ball-check valve is inserted into the cylinder casing.
Parts in the forward, intermediate, and direct clutches that already seem to be shared are the ball-check valves and the clutch-pack retaining rings.
Instead of ball-check valves
, system uses rotary flow-control valves.