MAINTENANCE Made Easy
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AMONG the several factors which have a bearing on the need to adjust long-established maintenance policies are comprehensive credit finance facilities, which permit more frequent replacement of fleets, and the subsequent decrease in the need for major overhauls.
Having re-assessed the maintenance requirements of his fleet, an operator would normally have three broad alternatives as to how to carry out the work.
Maintenance could be reduced simply to servicing, by frequent replacement of vehicles. Apart from saving the cost of major overhauls, the operator need not burden himself with expensive garage equipment. Many successful operators, however, prefer to have complete control of the maintenance of their vehicles. Adequate repair staff and facilities are provided and a preventive maintenance policy is usually adopted.
Though formerly accepted as the most economic and reliable means of keeping vehicles operational, this system can be overdone. One reason could be that the original estimate of the probable life of vehicles was either too conservative or had not taken into account subsequent technical advances.
Another Method
Another method is for the operator to do his own maintenance, but to rely only on drivers' reports and periodic fitters' tests to determine what work shall be done.
When vehicles are replaced frequently, even the servicing may be done by the local garage in accordance with manufacturers' schemes. The operator is then relieved of even this responsibility and only the hire of vehicles would further reduce responsibility for the supply and upkeep of his fleet. By employing agents to carry out servicing and light maintenance, the recording of these items of running cost would consist of an analysis of the invoices received from the garage concerned.
The practicability of a preventive maintenance scheme may well depend on the type and make of vehicle, and the work on which it is employed. These factors will influence the mileage at which the various degrees of maintenance become necessary.
B20 Main objectives of preventive maintenance are to eliminate unscheduled delays in operation and to provide a steady flow of work for the fitting staff. The latter requirement calls for sufficient groups of similar vehicles to allow a regular plan of work to be carried out. Even then, if these were liable to be engaged on widely differing types of work it would be difficult to determine, in advance, the mileage at which it would be economic to carry out specified maintenance tasks.
Side of Safety Even greater responsibility is called for in planning the maintenance of road transport vehicles because public safety is involved and the person charged with this responsibility should tend to err on the side of safety. Shrewd judgment is required to draw a fair balance between excessive caution which could provide a cover for inefficiency, and a standard of roadworthiness which would give a satisfactory and economic service to the customer.
If the operator's circumstances are such that a policy of preventive maintenance would meet his needs, it is then necessary to draw up a schedule of tasks, of increasing thoroughness, undertaken on a basis of time or mileage. In practice, this may well apply to an established haulier whose average weekly mileages tend to be similar.
The basis of such a scheme would be the manufacturer'i hand-book, but because most fleets have variations in type, and possibly make, it will be convenient to devise a workable compromise in the interest of standardization.
Allowing for such variations, the following schedules suggest the manner in which a preventive maintenance scheme could be drawn up: Dependent upon the average weekly mileage, schedule A could be carried out, say. fortnightly, schedule B. every two months, schedule C, half yearly and schedule D, annually. Appropriate forms should be drawn up.
The schedule A form could be headed "Vehicle number" together with the date on which the work was carried out and the mileometer reading at the time The form is then (Continued on page 333) divided into four vertical columns; the, first two being headed " Service." For easy reference, these are first listed numerically. En the next Column are detailed the services performed. These are as follows: Lubricate all points detailed in the manufacturer's chart; Wash vehicle and clean interior of cab; Check for loose road wheel nuts and body bolts; Tyres—check pressures, including spare, and examine for wear and cuts; Cheek and top up brake fluid level; Report on engine; Report on brakes; Report on steering; Report on transmission; Report on charging rate. starter, lamps, horn, screen-wiper-and traffic indicators.
Ticked Off
The third vertical column alongside the 10 servicing items allows a tick or initials when the work has been completed. The fourth column is used to report any additional defects under the varions headings.
Beneath this section the fitter certifies the complete service and enters whatever spares have been required. In some organizations, however, particularly where drivers are allocated to one vehicle only, they are permitted to do some of their own maintenance. It would then be the driver who certified that the work had been done.
The form used for schedule B has a similar heading and is again. divided into four vertical•columns, but there are now seven service duties to be performed.
These are: Engine—Check for oil and fuel locks, check and, clean plugs, check valve and tappet clearances and distributor leads, clean and adjust points, adjust clutch pedal travel, lubricate water pump. Brakes—Test and adjust. Steering—Test and checkfor slack bolts. Transmission—Top up gearbox and back axle, grease hubs. Body and chassis—Examine springs and U-bolts, tighten all nuts, bolts and road-spring clips, tighten screws on doors, hinges, and bonnet fastenings, top up shock absorbers. Tyres—Examine and rotate as required. Electrical equipment—Check dynamo, starter, lamps, horn, screen-wiper and traffic indicators, lubricate starter motor.
As schedules C and D are much more comprehensive, they will invariably be carried out by fitting staff and will include a road test report which is divided into nine items and listed on the reverse side of the form. The items read: Engine; Gearbox; Transmission; Back axle; Brakes; Steering; Road springs; Electrical system; Bodywork. Provision is made for reports before and after servicing.
The main section of the form for schedule C details the seven services to be performed. They are: Engine—Carry out schedule B service; check fuel pumps and clean filters, tighten cylinder-head nuts and manifold, drain sump and refill, clean
oil filters, renew cartridge, clean air filters, check fan-belt tension, flush radiator. Brakes—Carry out schedule B service. Steering—Carry out schedule B service; check all joints and take up play, check front-wheel track. Transmission—Carry out schedule B service; check and tighten propeller shafts.
• Body and chassis--Carry out schedule B service, repack roadwheel bearings with lubricant, tighten spring shackles, check lubrication of speedometer cable, repair body as necessary. Tyres—Examine and rotate as required. Electrical equipment— Carry out schedule B service. The form for sledule D is similarly drawn up to allow for a test report and the seven items of servicing now read: Engine Carry out schedule B and C service, clean injectors (CI engines), decarbonize engine and grind in valves. Brakes • Carry out schedule B service,remove drums, check linings. Steering—Carry out schedule B and C service. Transmission , Carry out schedule B and C service, drain gearbox and back axle, and refill. Body and chassis—Carry out schedule B and C service. Tyres—Examine, rbtate as required, Electrical equipment—Carry out schedule B service..
Sequence Chart
In addition to these four forms which refer to the work carried out on individual vehicles, it will also be necessary to devise a chart setting out the sequence of maintenance for the whole fleet over a period of -six or twelve months. For example,, such a chart could be divided horizontally according to the number of vehicles in the fleet and vertically into as many columns as there were weeks in the period under review.
Also, it would be necessary to ensure that the balance between the number of A, B, C and D schedules to be performed in any one week bore. relation to the availability of semi-skilled and skilled fitting staff.
Many operatdrs find it convenient to keep a brief record of the date on which each of these particular schedules is performed on every vehicle, A standard card index form, divided vertically into five columns, is suitable for this purpose. On the left would be the week-ending date, followed by the weekly mileage, mileage to date, fuel average and finally service record.
In addition to records relating to the organization of maintenance, larger operators, at least, would also need to keep analysis sheets of repair expenses. These should segregate costs as between labour and materials. It would also be of advantage' to separate scheduled repairs done in 'connection with, a preventive maintenance programme, and unscheduled work resulting from either breakdowns or faulty original maintenance.