PART IV

MAINTENANCE

401. ROUTINE MAINTENANCE.

(a) The following policy of routine inspection and overhaul has been established:

(b) Between these inspections and overhauls there are certain operations which must be performed by the operator. This section of these instructions is designed as a guide for the operator of the ECM, who must necessarily be responsible for the daily maintenance and up-keep of the ECM. Only a small amount of time is necessary to insure that the machine is properly maintained. Some maintenance duties must be performed daily, others require only a few minutes each week. A machine which is properly maintained will give a minimum of trouble.

402. LUBRICATION.

(a) The Spare Parts Box (ENG 109) issued with each machine supplies oil, grease and a one drop oil can.

(b) (1) Plates 3 and 4 are included to assist in locating the oil holes of the various units. It will be noted that, in many of the parts, felt wicks have been provided to receive the oil rather than the bearing surfaces of the parts themselves.

(2) CARE SHOULD BE TAKEN TO PREVENT OIL OR GREASE FROM GETTING ON THE CODE WHEELS, INDEX WHEELS, CIPHER UNIT, SEPARATORS, CONTROLLER AND KEYLEVER CONTACTS AND WIRING.

(c) Oil the following points sparingly, once every two weeks.

PLATE 3

PLATE 4

(e) At the time of oiling, (and more often if necessary) wipe the Code Wheel spindles with an oily cloth. The Code Wheels must not run on a dry spindle.

403. CLEANING CONTACTS.

(a) Experience has shown that the major cause of unreliable operation is dirty contacts of the Cipher Unit. Clean contacts are absolutely necessary for proper functioning of the machine. The only reliable method of maintaining clean contacts, except where an approved Code Wheel lubricant is used, is to follow a daily cleaning schedule. This will not only insure the removal of any dirt which may have been deposited but also will remove any "carried over" metal which may have been ground off the contacts.

(b) The lid should be removed only as required for changing Code Wheels, making Index Settings, lubrications, etc. It should be kept in place at all other times.

(c) (1) The plunger-contacts of the Cipher Unit must be inspected and cleaned DAILY, except where an approved Code Wheel lubricant is used. The Spare Parts Box (ENG 109) contains a canvas paddle which is especially designed to fit between the Cipher Unit Separators. The outside plunger contacts should be rubbed with one side of the canvas paddle.

(d) To clean the contacts of the Code Wheels, place a piece of canvas on a smooth flat surface and rub the Code Wheel and Index Wheel contacts against the canvas until they have become clean and bright. If in some cases the hub of the Code Wheel will not permit the Code Wheel to lay completely flat, two blocks should be laid side by side with a space between them, forming a depression in which the hub of the Code Wheel will ride, permitting the Code Wheel Contacts to lay flat on the canvas,

(e) If, because of infrequent cleaning, the contacts cannot be cleaned with the canvas paddle, a pencil (not ink) eraser may be used. The standard flat type, about two inches long is a convenient size. It must be clean and free from abrasive material. The use of the eraser must always be followed by cleaning with the canvas paddle.

(a) A special Code Wheel Lubricant is being made available to all holders. Initially small quantities will be forwarded to the Registered Publication Issuing Offices, as a matter of convenience in distribution, but regular distribution will be through the ECM Repair Facilities.

(b) Until the lubricant is available, or if the supply is temporarily exhausted, the standard method of cleaning Code Wheels should be followed.

(c) The use of the Code Wheel lubricant requires the cleaning of the Cipher Unit and Code Wheel contacts at intervals of two four weeks instead of daily.

(d) The approved lubricant is commercially known as "Lubriplate" formula 105.

(e) "Lubriplate" is light cream in color and has a viscosity similar to petroleum jelly.

(f) To apply "Lubriplate":

(g) "Lubriplate" should be applied at intervals of two to four weeks, depending upon use and local conditions.

(h) THE USE OF ANY OTHER LUBRICANT, OR OF "LUBRIPLATE" IN ANY FORMULA OTHER THAN "105" IS NOT AUTHORIZED.

INFREQUENT OPERATIONS

405. PRINTER RIBBON.

(a) A standard 1/2 inch typewriter carbon ribbon (such as used on an Underwood typewriter) is used on the Printer. A Hectograph ribbon may be used if preferred.

(b) The ribbon feed Is reversed by moving the ribbon reverse lever towards the spool upon which the ribbon is to be wound.

(c) Only one-half of the ribbon is used at a time, and after one-half fails to print clearly, the ribbon should be inverted to use the other half. This is accomplished by reversing the respective positions of the spools (i.e., the left spool to the right position and the right spool to the left position) and replacing the ribbon in the ribbon guide. When replacing the spools on the shafts be sure the small pin on the hub of the shaft engages the spool, thus preventing the spool from slipping on the shaft.

406. PAPER TAPE REPLACEMENT.

(a) Paper tape is a "supply" Item and is not normally procurable from ECM Repair Facilities or Registered Publication Issuing Offices. In some cases, a small supply of tape is carried in stock at these places, but only as an emergency supply. Each ship or station should anticipate its needs and order an adequate stock well in advance of actual needs. Activities from whom paper-tape can be obtained are as follows:

(b) The paper tape used in the ECM Mark 2 is a special gummed tape made according to U.S. Navy specifications. It is not affected by high humidity and will not become loosened from the message blank with age. Ordinary 3/8 Inch paper tape (plain or gummed) may be used in an emergency, but it is not recommended. Two types of special ECM tape are available:

407. CAUTIONS.

(a) Throughout this publication, several "Cautions" have been Inserted. Those which affect the maintenance and upkeep are summarized as follows: