Usage:
All 3208 Truck Engines
Engine repairs can be done before failure or after failure. Before failure repairs normally cost between 5 and 25% of the price of a new engine. After failure repairs can cost as much as 65% or more of the price of a new engine.
Good maintenance practices will increase the engine service life and make it possible to see signs or indications of needed future repairs. If the correct repairs are made immediately, the cost of the repairs and the "downtime"(out of operation time) will be less.
Good maintenance is more than just oil and filter changes. An accurate record of the engine's history must also be kept. This will include such items as serial number, arrangement number, date engine was put in operation, type of application, total amount of fuel and oil used, type of oil used, S.O.S. (Scheduled Oil Sampling) reports and a complete list of all maintenance and repairs. This record will make it possible to see gradual changes in the engine's performance and its cost of operation. Knowledge of these changes is important, and can be used by the customer or serviceman as repair indicators.
Repair indicators are any signs or indications which tell the customer or serviceman that the engine needs maintenance or repair. There are two types of repair indicators, as shown in the diagram -planned indicators (before failure) and problem indicators (after failure).
Planned Indicators
Use of planned indicators permits you to plan repairs and decrease the possibility of a sudden, unexpected failure. Planned indicators also will let you know at what point in time you should more closely look at the engine's condition. Several important planned indicators are: Scheduled Oil Sampling (S.O.S.); hours, units or miles of operation; total fuel used and the time in operation.
S.O.S. is the most accurate method available to find out the internal condition of the engine. Information from S.O.S. makes it possible to estimate the approximate time in the engine's service life repairs will most likely be needed. This makes a preventive-type repair possible. This can decrease the possibility of a sudden engine failure.
Hours, units or miles of service can be used to plan maintenance intervals.
Total fuel used means that an accurate record of the amount of fuel the engine has used (consumed) must be kept. This information can then be used to tell when to take a closer look at the engine's internal condition. Total fuel used is a direct comparison to the amount of work performed by the engine. Use of hours, units or miles of operation does not take into effect the amount of time the engine was idling or the load that was on the engine. An example of the information from total fuel used is as follows:
NOTE: These amounts of fuel are to be used only as a guideline. The amounts that must be used in your particular application can be more or less than those shown in the chart. Factors such as load, quality of maintenance, and type of application will have an effect on the recommendations in the chart.
The time an engine has been in operation is not necessarily a direct indication of the amount of work performed by the engine. It can, in some applications, be used to predict the desired time for repairs or overhaul. In applications where specific operation and safety inspections must be made at regular intervals, the time in operation can be used to plan a repair or overhaul for the same time as an inspection.
Changes in valve clearance settings can be recorded for each valve on each cylinder. These changes will give an indication of the amount of wear on the components in the valve mechanism area.
Problem Indicators
A problem indicator is directly related to changes in engine operation or performance. Most problem indicators such as increased oil or fuel consumption, excessive smoke, increased blowby and changes in oil pressure can be found as they develop. The customer and serviceman must remember that indicators like oil consumption and blowby are not a sign of a problem just because the rate is not what you expect. A sudden increase in this rate is a problem.
In most applications, a total failure can be prevented, if corrective action is taken at the first sign of a problem. When a problem indicator is first noticed it must be checked immediately to find how serious the problem is.
It must be remembered that problems do not always develop gradually. If there is a sudden component failure or development of a problem indicator, repair must be made immediately to prevent increased damage to the engine.
When repair indicators are used correctly, they will permit the engine to be operated at a minimum cost during its service life.