Control Manifold Cartridge Valve Service - Toro Groundsmaster 4500-D Series Service Manual

Control Manifold Cartridge Valve Service

Groundsmaster ® 4500-D/4700-D
19245SL Rev A
1. Make sure the control manifold is clean before removing the cartridge valve
from the control manifold.
2. If cartridge valve is solenoid operated, remove nut securing solenoid coil to
the cartridge valve. Carefully slide coil off the valve.
Use care when handling the cartridge valve. Slight bending or
distortion of the stem tube can cause binding and malfunction.
When removing cartridge valve from manifold, make sure that deep
well socket fully engages the valve base.
3. Remove cartridge valve from manifold using a deep socket wrench. Note
correct location for O−rings, sealing rings and backup rings. Remove seal kit
from cartridge valve and discard removed seals.
4. Visually inspect the port in the manifold for damage to the sealing surfaces,
damaged threads and contamination.
5. Visually inspect cartridge valve for damaged sealing surfaces and
contamination.
A. Contamination may cause valves to stick or hang up. Contamination can
become lodged in small valve orifices or seal areas causing malfunction.
B. If valve sealing surfaces appear pitted or damaged, the hydraulic system
may be overheating or there may be water in the system.
Use goggles or other appropriate eye protection when using
compressed air for drying parts.
6. Clean cartridge valve using clean mineral spirits. Submerge valve in clean
mineral spirits to flush out contamination. Particles as fine as talcum powder
can affect the operation of high pressure hydraulic valves. If cartridge design
allows, use a wood or plastic probe to push the internal spool in and out 20
to 30 times to flush out contamination. Be extremely careful not to damage
cartridge. Use compressed air for cleaning.
7. Install the cartridge valve into the manifold:
A. Lubricate new seal kit components with clean hydraulic oil and install on
valve. The O−rings, sealing rings and backup rings must be arranged
properly on the cartridge valve for proper operation and sealing.
B. Dip assembled cartridge into clean hydraulic oil.
Use care when handling the valve cartridge. Slight bending or
distortion of the stem tube can cause binding and malfunction.
When installing cartridge valve into manifold, make sure that
deep well socket fully engages the valve base.
C. Thread cartridge valve carefully into manifold port by hand until the top
O−ring is met. The valve should go into manifold port easily without
binding.
IMPORTANT
CAUTION
IMPORTANT
Page 5–111 Hydraulic System: Service and Repairs