B3.9 and B5.9 Series Engines
General Safety Instructions
Section i - Introduction
General Safety Instructions
Important Safety Notice
Improper practices or carelessness can cause burns, cuts, mutilation, asphyxiation or other bodily injury or
Read and understand all of the safety precautions and warnings before performing any repair. This list contains the
general safety precautions that must be followed to provide personal safety. Special safety precautions are included
in the procedures when they apply.
Make sure the work area surrounding the product is dry, well lit, ventilated, free from clutter, loose tools, parts,
ignition sources and hazardous substances. Be aware of hazardous conditions that can exist.
Always wear protective glasses and protective shoes when working.
Rotating parts can cause cuts, mutilation or strangulation.
Do not wear loose-fitting or torn clothing. Remove all jewelry when working.
Disconnect the battery (negative [-] cable first) and discharge any capacitors before beginning any repair work.
Disconnect the air starting motor if equipped to prevent accidental engine starting. Put a ``Do Not Operate'' tag
in the operator's compartment or on the controls.
Use ONLY the proper engine barring techniques for manually rotating the engine. Do not attempt to rotate the
crankshaft by pulling or prying on the fan. This practice can cause serious personal injury, property damage,
or damage to the fan blade(s) causing premature fan failure.
If an engine has been operating and the coolant is hot, allow the engine to cool before you slowly loosen the
filler cap and relieve the pressure from the cooling system.
Do not work on anything that is supported ONLY by lifting jacks or a hoist. Always use blocks or proper stands
to support the product before performing any service work.
Relieve all pressure in the air, oil, fuel and the cooling systems before any lines, fittings, or related items are
removed or disconnected. Be alert for possible pressure when disconnecting any device from a system that
utilizes pressure. Do not check for pressure leaks with your hand. High pressure oil or fuel can cause personal
To prevent suffocation and frostbite, wear protective clothing and ONLY disconnect fuel and liquid refrigerant
(freon) lines in a well ventilated area. To protect the environment, liquid refrigerant systems must be properly
emptied and filled using equipment that prevents the release of refrigerant gas (fluorocarbons) into the atmo-
sphere. Federal law requires capturing and recycling refrigerant.
To avoid personal injury, use a hoist or get assistance when lifting components that weigh 23 kg [50 lb] or more.
Make sure all lifting devices such as chains, hooks, or slings are in good condition and are of the correct capacity.
Make sure hooks are positioned correctly. Always use a spreader bar when necessary. The lifting hooks must
not be side-loaded.
Corrosion inhibitor, a component of SCA and lubricating oil, contains alkali. Do not get the substance in your
eyes. Avoid prolonged or repeated contact with skin. Do not swallow internally. In case of contact, immediately
wash skin with soap and water. In case of contact, immediately flood eyes with large amounts of water for a
minimum of 15 minutes. IMMEDIATELY CALL A PHYSICIAN. KEEP OUT OF REACH OF CHILDREN.
Naptha and Methyl Ethyl Ketone (MEK) are flammable materials and must be used with caution. Follow the
manufacturer's instructions to provide complete safety when using these materials. KEEP OUT OF REACH OF
To avoid burns, be alert for hot parts on products that have just been turned off, and hot fluids in lines, tubes,
Always use tools that are in good condition. Make sure you understand how to use them before performing any
service work. Use ONLY genuine Cummins or Cummins ReCon replacement parts.
Always use the same fastener part number (or equivalent) when replacing fasteners. Do not use a fastener of
lesser quality if replacements are necessary.
Do not perform any repair when fatigued or after consuming alcohol or drugs that can impair your functioning.
Some state and federal agencies in the United States of America have determined that used engine oil can be
carcinogenic and can cause reproductive toxicity. Avoid inhalation of vapors, ingestion, and prolonged contact
with used engine oil.
Coolant is toxic. If not reused, dispose of in accordance with local environmental regulations.