Graco 312068M Repair, Flushing, Pressure Relief Procedure, Preventive Maintenance

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Repair

Flushing

Flush equipment only in a well-ventilated area. Do not spray flammable fluids. Do not turn on heaters while flushing with flammable solvents.

Flush out old fluid with new fluid, or flush out old fluid with a compatible solvent before introducing new fluid.

Use lowest possible pressure when flushing.

To flush entire system, circulate through gun fluid manifold (with manifold removed from gun).

Always leave some type of fluid in system. Do not use water.

Repair

Pressure Relief Procedure

Trapped air can cause the pump to cycle unexpectedly, which could result in serious injury from splashing or moving parts.

1.Select Park on Pump Control Switch if available, or turn off.

2.Turn off feed pumps.

3.Trigger gun to relieve pressure.

4.Close gun inlet valves.

5.Close fluid supply inlet valves.

6.Service spray gun. See corresponding spray gun manual.

Preventive Maintenance

When pumps are functioning properly, it is not unusual for a trace amount of resin to seep past the pump pack- ing onto the resin pump shaft. Routinely inspect shaft and wipe away any residue when the proportioner is turned off. Disassemble and clean the proportioning pumps annually. For pumpline P7758-255773, disas- semble and clean the proportioning pumps every six months. Inspect the pistons and cylinder for marks or scratches, which may cause leakage and damage to packings. Replace all packings, o-rings, and bushings annually. For pumpline P7758-255773, replace these items every six months.

312068M

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Contents Proportioning Pumps Models ContentsFlushing Pressure Relief ProcedurePreventive Maintenance RepairPumpline Reassembly Pumpline DisassemblyRepair Pump Base Reassembly Pump Base Disassembly#28 Pump Size Piston and Cylinder SealsSeal Alignment Pressed Seal Cylinder Assembly Seat Cylinder in BoreTools Required Hydraulic CylinderAssemble Rod Bushing to Port Block Attaching Retainer Plates and First Four Spacers Assemble Hydraulic Piston and Insert in CylinderInsert Piston into Cylinder Assembling Items onto Piston ShaftInstalling Hex Clevises and Baffle Jam Nut Installing Lube AdapterHold stationary Assembling Manifold Installing Final Four SpacersPumpline PartsPiston Assembly #28 Piston Assembly Item 25 Torque Specification Pump SizeSide Shown Piston Seal Kits Includes Parts 15, 18 Proportioning Pump Part Description QtyCylinder Seal Kits Includes Parts 13, 16 Proportioning Pump KitApply high strength thread sealant to threads Ring Part DescriptionParts Category Data Technical DataGraco Information Graco Standard Warranty