4342Replacement of Material Needle1. Unscrew the draw bar (pos. 24).2. Unscrew the cap (pos. 23) from piston casing (pos. 14).3. Pull the material needle (pos. 21) out of the piston casing.Installation of the remaining parts in reverse order.6 Cleaning6.1 Safety Warnings• Prior to any servicing and repair work: Make sure that the spray gun is inunpressurized condition, i.e. all air and material inputs must be shut off - if not,imminent risk of injury.• No open fires, naked light and smoking allowed in the work area. Whenspraying readily flammable media such as cleaning solutions, there is anincreased risk of fire and explosion.• Observe the safety warnings issued by the manufacturer. Aggressive and cor-rosive media represents risks and hazards to personal health.6.2 Cleaning - CompleteRegular cleaning and lubrication of the spray gun has to be performed, in order toincrease the service life and the function of the spray gun.Clean the gun only with cleaning solutions recommended by the manufacturer ofthe spraying material used at the time. It is important to make sure that cleaningsolutions do not contain any of the following constituents:• halogenated hydrocarbons (e.g. 1,1,1-trichloroethane, methylene chloride,etc.)• acids and acidiferous cleaning solutions• regenerated solvents (so-called cleaning dilutions)• paint removers.The above constituents cause chemical reactions with the electroplated compon-ents resulting in corrosion damage.WALTHER Spritz- und Lackiersysteme is not responsible for any damages resultingfrom such treatment.Clean the spray gun• prior to each change of the spraying medium.• at least once a week.• as often as may be required by the spraying medium handled and the resultantdegree of fouling.CautionNever immerse the spray gun in solvent or any other cleaning solution. The func-tional reliability and efficiency of the gun can otherwise not be guaranteed.CautionDo not use any hard, pointed or sharp-edged objects when cleaning the spray gun.Any damage of the precision-made parts are likely to affect your spraying results.1. Dismantle the spray gun in accordance with 5.5 Retooling the Spray Gun.2. Use a soft brush together with a compatible cleaning sulotion to clean the aircap and nozzle.3. Clean the remaining parts and the spray gun body with a suitable cloth andcleaning solution.4. Apply a thin film of the appropriate grease to the:• sealing collar of the piston• O-ring of the piston• material control needle• needle springMake sure to use a non-acidic, non-resinogenic grease and a soft brush.6.3 Cleaning - RoutineThe spray gun need not necessarily be dismantled for cleaning if and when thespraying medium is changed in regular intervals or upon termination of work (depen-ding on the material used).NoticeClean and lubricate the spray gun frequently in accordance with Chapter 6.2Cleaning - Complete. This will ensure functional reliability of the spray gun.The following requirements must be met before the routine cleaning work can beperformed:1. The material tank must be clean and then be filled with a compatible cleaningsolution. Material pressure has to be available at the spray gun.The cleaning solution should not be sprayed.2. Take the spray gun into operation (see 5.2 Starting the Spray Gun).3. Do not stop the spray gun until clear cleaning solution emerges from the nozz-le.The material supply of the PILOT WA 800 - WA 873 can be manually released sothat it is not necessary to operate the complete spraying system.All pressures should then be removed from the complete spraying system until thenext operation.1. Pull back the draw bar of the spray gun. The materialinlet is now open and both material duct and materialnozzle will be cleaned.2. Do not let go of the drawbar until clear cleaning solutionemerges from the nozzle.