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PARTS CATALOGUE / TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A [SPECIFICATIONS] Cal. No. 4F56A 8F56A 8F58A Item Movement The illustrations refer to Cal. 8F56A. (x 1.0) Movement ø18.5 x 17.7 (3H - 9H) x Outside diameter ø26.4 x 25.6 (3H - 9H) x 25.6 (12H - 6H) size 18.5 (12H - 6H)
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Reassembling procedures Figs.: Lubricating: Types of oil Oil quantity Moebius A Normal quantity Moebius V Moebius F Cal. 4F56A, 8F56A & 8F58A Ex. : Cal. 8F56A 24-hour, Hour, Minute and second hands Dial Holding ring for dial 0884 167 (4F56A) 0884 166 (8F56A,8F58A) Please see the remarks on the following pages.
PARTS CATALOGUE Cal. 4F56A, 8F56A, 8F58A Note Pull out the crown to the first click before starting disassembling or reassembling. Cal. 4F56A, 8F56A & 8F58A It is highly recommended that the exclusive movement holder (S-680) be used for Ex. : Cal. 8F56A disassembly or reassembly.
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PARTS CATALOGUE Cal. 4F56A, 8F56A, 8F58A Cal. 4F56A, 8F56A & 8F58A Ex. : Cal. 8F56A Note Never remove the 24-hour wheel and date driving wheel while working on the date dial 14 Date dial guard 0808 127 r e p l a c e m e n t ( w i t h o u t...
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Case ring The type of case ring is determined based on the case design. Check the case number and refer to “SEIKO Casing Parts Catalogue” to choose the appropriate case ring. 7 Circuit block cover...
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The type of date dial is determined based on the case design. * Not all the types of date dial are shown in the table above. Check the case number and refer to “SEIKO Casing Parts Catalogue” to choose the appropriate date dial. 43 Setting stem 0351 196 The type of setting stem is determined based on the case design.
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Cal. 4F56A, 8F56A, 8F58A TECHNICAL GUIDE • The explanation here is only for the particular points of Cal. 4F56A, 8F56A and 8F58A. • For repairing, checking or measuring procedures, refer to the “TECHNICAL GUIDE, GENERAL INSTRUCTIONS”. STRUCTURE OF THE CIRCUIT BLOCK [ Cal.
TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A REMARKS ON DISASSEMBLING AND REASSEMBLING It is highly recommended that the exclusive movement holder (S-680) be used to disassemble or reassemble the watch. Use of other movement holders may make unreliable the screw pins (the gold part) of the main plate.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A 1 24-hour, hour, minute and second hands Always set the hands with the battery installed. Set the movement to the A portion of the exclusive movement holder. If any other movement holder is used, be certain to place the movement on a secure, flat plate. Pay special attention not to damage the hooking portion.
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It is highly recommended that the exclusive tool (S-912) be used for removing or installing the battery, resetting the built-in IC or inputting the calendar data. Contact SEIKO SERVICE CENTER to purchase this exclusive tool. S-912 How to remove the battery 1.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A How to install the battery 1. In a case where a red battery insulator is installed, remove and discard it. 2. To install a new battery with a battery insulator, align the tip of the arrow mark on the seal attached to the battery with the crown.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A How to input the calendar data How to check the calendar data (after battery change) 1. Pull out the crown to the first (or the second) click, then immediately push it back to its original position.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A How to input the calendar data To input the calendar data, activate the circuit by contacting each terminal and the side face of the battery repeatedly with tweezers. Be careful not to damage the circuit block.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A 3. Contact the “Y” terminal with the tip of tweezers until the year [8F] number representing the current year appears in the calendar frame. (Refer to the table below for the year number.) [4F] [Ex.
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Cal. 4F56A, 8F56A, 8F58A TECHNICAL GUIDE How to check the calendar data (After inputting the data) Ex.: July 12, 2002 Pull out the crown to the first click, then immediately push it back to its original position. Gently support the battery with fingers to securely hold the movement.
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Cal. 4F56A, 8F56A, 8F58A TECHNICAL GUIDE Note Pull out the crown to the first click before starting disassembling or reassembling. 7 Circuit block cover Reassembling : When setting the circuit block cover, take care not to deform the terminal for battery check.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A 9 Date driving contact point spring 10 24-hour contact point spring • Setting position Date driving contact point spring 24-hour contact point spring Note The date driving contact spring and the 24-hour contact point spring contact with the circuit block to drive and control the ultrasonic motor.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A Protrusion D • How to install 1. Put the date dial guard on the main plate so that the A and B portions are over the guide pins, as shown in the illustrations at the right.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A 25 Intermediate date driving wheel and pinion 27 Ultrasonic rotor 28 24-hour wheel 24-hour wheel 29 Date driving wheel Ultrasonic rotor • Setting position Intermediate date driving Refer to the illustration at the right.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A 31 Train wheel bridge Step rotor • Setting position of the wheels Fifth wheel and pinion Setting wheel Minute wheel and pinion Fourth wheel and pinion Third wheel and pinion 36 Setting wheel Make sure that the top face is up.
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TECHNICAL GUIDE Cal. 4F56A, 8F56A, 8F58A III. VALUE CHECKING Coil block resistance 3.6 KW ~ 4.0 KW Measuring the coil block resistance Measure the resistance with the coil block installed on the main plate. Apply the red and black probes of the tester to the patterns of the coil lead terminal. While doing so, take care not to touch the end portion of the coil lead terminal, as this will break the coil wire.
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Time accuracy adjustment by crown operation 【Supplement】 (Only recommended to the Service Centers of SEIKO Affiliates and Distributors) Although time accuracy is normally adjusted by pattern cutting (P.21), in case it cannot be adjusted within the standard accuracy by this method, please adjust by the crown operation which is shown below:...
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Tips on repairing the perpetual calendar (4F,8F Series) • Be aware that incorrectly-input calendar data will cause a wrong calendar display. • For troubleshooting problems with the calendar, refer to the table below. Symptoms Problems Solutions Reference p.11,12 • The calendar does •...
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