Storch Airless ST 850 Mode D'emploi page 170

Problem
Pump output is low
Motor runs but pump does not
stroke
Excessive paint leakage into
throat packing nut
Fluid is spitting from gun
Original instruction
What to check
If check is OK, go to next check
Prime valve leaking.
Verify pump does not continue to
stroke when gun trigger is released.
(Prime valve not leaking.)
Leaking around throat packing nut
which may indicate worn or damag
packings.
Pump rod damage.
Low stall pressure.
Piston packings are worn or dama-
ged.
O-ring in pump is worn or dama-
ged.
Intake valve ball is packed with
material.
Large pressure drop in hose with
heavy materials.
Check extension cord for correct
size
Loose motor brushes and terminals. Tighten terminal screws. Replace brushes if
Worn motor brushes. (Brushes
must be 13 mm minimum length).
Broken and misaligned motor brush
springs. Rolled portion of spring
must rest squarely on top of brush.
Motor brushes are binding in brush
holders.
Connecting rod assembly damaged.
See pump manual.
Gears or drive housing damaged.
Throat packing nut is loose.
Throat packings are worn or dama-
ged.
Displacement rod is worn or dama-
ged.
Air in pump or hose.
Spray tip is partially clogged.
Fluid supply is low or empty.
170
What to do
When check is not OK, refer to this column
Follow Pressure Relief Proced then repair pri-
me valve.
Service pump. See pump manual.
Replace packings. See pump manual. Also
check piston valve seat for hardened paint or
nicks and replace if necessary. Tighten packing
nut/wet-cup.
Repair pump. See pump manual.
Turn pressure knob fully clockwise. Make sure
pressure control knob is properly installed to
allow full clockwise position. If problem per-
sists, replace pressure transducer.
Replace packings. See pump manual.
Replace o-ring. See pump manual.
Clean intake valve. See pump manual.
Reduce overall length of hose.
See Extension Cords
leads are damaged.
Replace brushes.
Replace spring if broken. Realign spring with
brush.
Clean brush holders, remove carbon dust with
a small cleaning brush. Align brush lead with
slot in brush holder to assure free vertical brush
movement.
Replace connecting rod assembly. See pump
manual.
Inspect drive housing assembly and gears for
damage and replace if necessary.
Remove throat packing nut spacer. Tighten
throat packing nut just enough to stop leakage.
Replace packings. See pump manual.
Replace rod. See pump manual.
Check and tighten all fluid connections. Cycle
pump as slowly as possible during priming.
Clear tip. See Cleanup.
Refill fluid supply. Prime pump. See pump
manual. Check fluid supply often to prevent
running pump dry.