procedures for gasoline engines are also much the same as those for diesels; however. there is one important exception. Most gasoline engines are equipped with priming or choking devices to aid in starting a cold engine. Generally, these priming devices simply dump raw fuel into the cylinders; that is, the fuel is not thoroughly mixed with air or atomized before induction into the cylinders. This rich mixture of fuel aids in achieving initial combustion; however, not all of the fuel is burned. In other words, we have incomplete combustion. Prolonged or excessive choking during and after the start can lead to carbon deposits being built up in the engine. For this reason, the operator should always use care and restraint in choking or priming the engine. both during and after the start.

Securing procedures for gasoline engines are also basically the same as those for diesels. although some gasoline engine installations may not permit circulation of lube oil and coolant after the engine has been stopped.

As you might expect, operator maintenance routines for gasoline engines differ from those for diesels because of the slight differences in design and construction of gasoline engines. In other words, gasoline engine maintenance and inspection schedules must provide for the inspection, the adjustment, and the maintenance of such items as carburetors, chokes, ignition coils, wiring. distributors. and spark plugs.

SAFETY. - Anytime gasoline or diesel engines are secured for maintenance and inspection purposes, the operator should always guard against intentional or inadvertent starting of the engine by uninformed personnel. This rule applies to all types of prime movers, including electric motors. It also applies to maintenance and inspection operations being performed only on the driven equipment. Regardless of whether the work is being done on the prime mover itself or on the driven equipment alone. unintentional starting of the prime mover during the maintenance operation can result in serious damage to the machinery and serious injury to maintenance personnel. For this reason. YOU are responsible for using the equipment tag-out procedures contained in the current OPNAVINST 3120.32. In most situations, it may be a good idea to disable the starting mechanism completely, so even if personnel fail to see or read the tag, the prime mover cannot be started.

During the maintenance operation, the operator must keep a strict accounting of all tools and parts. Tools, nuts and bolts, or any other material left adrift can foul a moving part and completely disable the machinery during subsequent operation. There is another reason for keeping a strict accounting of parts whenever components are disassembled. Parts that work together wear together. The various parts of valve assemblies, bearing assemblies, and so forth, should be carefully marked and grouped during disassembly and replaced in the same position from which they were removed; otherwise, discrepancies in fitting and joining can result and reduce the mechanical efficiency of the moving parts. This can eventually lead to a breakdown.

WARNING

When an engine or a motor is inspected that is in operation, the operator should always be cautious while working near moving parts. Loose clothing, rags hanging from pockets, dangling key chains, and so forth, can easily become entangled with, or drawn into, moving parts, resulting in a serious accident.

CLEANLINESS. - Engine maintenance and inspection require cleanliness. Dirt allowed to accumulate on and around an engine can find its way inside that engine. It may be carried into the engine with air, fuel, lube oil, or water, or careless personnel may introduce it. Dirt can cause sludge and scale deposits that impair circulation of fuel, oil, and water, and erode moving parts. Large accumulations of dirt on external surfaces can insulate the surface and reduce cooling.

Normally, there are specific instructions available locally concerning cleanliness precautions while handling fuel and lube oil. You must know and observe these precautions. Some fundamental cleanliness precautions are as follows.

Never use waste or linty rags around fuel or lube oil containers, fuel inspection equipment, or carburetors.

Keep fuel and lube oil handling equipment, such as measures, funnels, and containers, clean and covered when not in use.

Use clean, soft water in engine radiators and coolant systems to keep the engine water jackets free of sediment, and use distilled water in topping off batteries.