Pinpointing external leaks,UV leak DYE, Pinpointing internal leaks,Diagnosing oil pressure problems(Last Page of Engine Lubrication system)

Pinpointing External Leaks:

External leakage can be detected visually in most cases. The external oil leaks from engine gaskets or seals are the easiest to find. An oil leak my be so small that it is not noticed or so large that the who engine is covered with oil.
To diagnose large leaks, wash the engine off and run it in short cycles to prevent a flood of oil from covering a large area around the leak a second time.
Small leaks can be diagnosed by washing the leak area off, letting it completely dry, and coating it with a tracing powder can be used for this purpose.
Spray the general area of the leak with the foot powder. The resulting white powder film will stick to the engine. Then, run the engine for a half-hour or so in the shop, or drive the vehicle fairly slowly in a parking lot or on a clean, dry road. Keep both vehicle speed and engine RPM slow.

UV Leak DYE:

Another way to pinpoint small, difficult-to-trace oil leaks is by adding leak dye to the engine oil. A UV (ultraviolet) light can then be used to find the location of the leak. When viewed under the UV light. The dye glows a bright greenish/yellow. This may be the best way to pinpoint small leaks that occur only during special circumstances, such a driving vibrations, road shock, or flexing of components and lines.
When you use the dye, follow the dye kit directions. Larger leaks will show up within a short time once the dye has been added to the engine oil and the engine has been run. Fore smaller, less obvious leaks, you may have to add the dye to the oil and wait for days.
To see the leak, put on the UV glasses. Next,turn on the UV light, shine it on the area you suspect to see leaking and look for a trail of dye from the bottom of the engine upwards. Once the trail is visible under the light, follow it up to the highest point to find the source of the leak.

Pinpointing Internal Leaks:

Internal leakage can be very difficult to detect. Modem engine run at high internal engine temperatures and are also equipped with very efficient catalytic converters. These can mask internal oil leaks. Oil can leak or be drawn into the induction system via several different paths. Some of the more common causes of internal leakage include:
Intake Manifold Gaskets: Oil can enter the intake manifold at any point where oil is close to a leaking intake manifold gasket. Most V-type pushrod engines are designed so that the intake manifold covers the "valley" containing the camshaft, lifters and pushrod. Intake manifold gasket failure on these engines can allow manifold vacuum to suck oil past the leaky gasket into the intake ports where it is delivered with the air/fuel mixture to the cylinder.
A failed intake gasket can cause oil to be drawn from the valve train area under the valve cover, and from the area underneath the intake manifold itself.

Diagnosing oil Pressure Problems:

Along with oil consumption problems, the next most common lubrication system problems relate to engine oil pressure, flow, and volume.
The three most common oil pressure problems are as follows:
Low oil pressure, which can be indicated by low oil pressure gauge reading, or an oil pressure indicator light coming on while the engine is running. Abnormal engine noises (knocks, rattles, ticks or other mechanical noise) may also be noticeable.
High oil pressure, which can be indicated by high or excessive oil pressure gauge readings, or an obviously swollen oil filter housing.
A malfunctioning oil pressure indicator light or gauge circuit, which can indicate that there is an oil pressure problem when the system is actually functioning normally. The diagnosis should beging with checking engine oil level. The dipstick should read full when checked, and the oil should be clean and of the correct viscosity as specified by the engine manufacturer.
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