DIAPHRAGM 4578986 - Caterpillar

Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
Accidental machine starting can cause injury or death to personnel working on the machine.To avoid accidental machine starting, turn the battery disconnect switch to the OFF position and remove the key. If the machine is not equipped with a battery disconnect switch, disconnect the battery cables from the battery and tape the battery clamps.Place a do not operate tag at the battery disconnect switch location to inform personnel that the machine is being worked on.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Welding Requirements
Welding quality is critical to the success of the installation procedures. Welds must be smooth and continuous. Do not undercut the welds. No overlap is allowed. Grind the ends of the welds to a smooth radius.Prepare the metal for welding according to the next section. Refer to the illustration in this special instruction for welding symbols and specifications.Be sure that all electrodes are dried. The electrodes can be dried by heating the electrodes to 300° C (572° F). the electrodes must be dried for at least 30 minutes.Do not weld in windy conditions. Do not weld when temperatures are below 16° C (60.8° F).Penetrations characteristics may vary greatly depending on the following conditions:
Electrode diameter
Shielding gas
Welding current
Plate thicknessThe following items also affect the welds:
Geometry of welded joints
Surface conditions
Composition of the base metal and of the electrodeFor more welding information, consult the Special Instruction, REHS1841, "General Welding Procedures".Preparing the Metal for Welding
Personal injury can result from flame cutting or welding on painted areas.The effect of gasses from burned paint is a hazard to the person doing the cutting or welding.Do not flame cut or weld on painted areas.
Before carrying out arc welding on the machine or on any equipment attached to the machine, disconnect all power and ground leads from the batteries in order to avoid possible damage to electronic components.
All grease, paint, and foreign object must be removed before welding. Any of these materials will discharge gas which will cause porosity in the weld deposit. Water and rust will cause hydrogen embrittlement. Hydrogen embrittlement causes cracks in the weld deposit.Remove foreign objects with a wire brush, a buffer, or