These instructions are a review of many items which a serviceman encounters in servicing and maintaining a truck engine.
PROBLEM ANALYZING: In analyzing a system malfunction, use this systematic procedure to locate and correct the problem.
- 1. Determine problem.
- 2. List possible causes.
- 3. Devise checks.
- 4. Conduct checks in logical order to determine cause.
- 5. Consider remaining service life against cost of parts and labor.
- 6. Make necessary repair.
- 7. Recheck.
SAFETY: Your safety and that of others is always the number one consideration when servicing or maintaining trucks and truck engines. Safety is a matter of thoroughly understanding the job to be done and the application of good common sense. It is not just a matter of "do's" and "don'ts".
CLEANLINESS: The most important single item in assuring long engine life is to keep dirt out of vital working parts. Precautions have been taken to safeguard against this. Enclosed compartments, seals and filters have been provided to keep the supply of air, fuel, coolant and lubricants clean. It is important that these safeguards be maintained.
Whenever fuel, lubricating oil, coolant lines or air lines are disconnected, clean the point of disconnection as well as the adjacent area. As soon as the disconnection is made, cap, plug or tape the line or opening to prevent entry of foreign material. The same recommendations for cleaning and covering apply when access covers or inspection plates are removed.
Clean and inspect all parts. Be sure all passages and holes are open. Cover all parts to keep them clean. Be sure parts are clean when they are installed. Leave new parts in their containers until ready for assembly.
REMOVAL AND INSTALLATION: Use a hoist to remove heavy components. Engine removal should be accomplished by using an adjustable lifting beam. All supporting members (chains and cables) should be parallel to each other and as near perpendicular as possible to the top of the object being lifted.
When it is necessary to remove a component on an angle, remember that the capacity of an eyebolt diminishes as the angle between the supporting members and the object becomes less than 90°. Eyebolts and brackets should never be bent and should only have stress in tension.
Some removals require the use of lifting fixtures to obtain proper balance and to provide safe handling.
If a part resists removal, check to be certain all nuts and bolts have been removed and that an adjacent part is not interfering.
DISASSEMBLY AND ASSEMBLY: When servicing or repairing the engine, complete each step in turn. Do not partially assemble one part and start assembling some other part. Make all adjustments as recommended. Always check the job after it is completed to see nothing has been overlooked.
BOLTS AND BOLT TORQUE: Use bolts of the correct length. A bolt which is too long may "bottom" before the head is tight against the part it is to hold and cause failure. The threads in the assembly can also become damaged when a "long" bolt is used.
If a bolt is too short, there may not be enough threads to hold the part securely.
Apply proper torque values to all bolts and nuts when assembling AVSpare equipment. When a specific torque value is required, the value is given in the instructions. Tighten all other bolts and nuts for general usage or taperlock studs to the torque values given in the TORQUE SPECIFIAVSIONS.
LOCKS: Lockwashers, flat metal locks or cotter pins are used to lock nuts and bolts.
Flat metal locks must be installed properly to be effective. Bend one end of the lock around the edge of the part. Bend the other end against one flat surface of the nut or bolt head.
Always install new locks in compartments which house moving parts.
When installing lockwashers on housings made of aluminum, use a flat washer between the lockwasher and the housing.
LINES AND WIRES: When removing or disconnecting a group of lines or wires, tag each one to assure proper assembly.
LUBRIAVSION: Where applicable, fill the compartments of the components serviced with the amount, type and grade of lubricant recommended in the Lubrication Instructions.
RUST PREVENTIVE COMPOUND: Clean the rust preventive compound from all machined surfaces of new parts before installing them.
SHIMS: When shims are removed, tie them together and identify them as to location. Keep shims clean and flat until they are reinstalled.
GASKETS: Be sure the holes in the gaskets correspond with the lubricant passages in the mating parts. If it is necessary to make gaskets, select stock of the proper type and thickness. Be sure to cut holes in the right places. Blank gaskets can cause serious damage.
When removed, always install new cylinder head and manifold gaskets using recommended gasket compound on head gaskets to allow uniform sealing.