Bulova Series 218 User manual

ACCUTRO
Service Manual N
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by BULOVA

1
PATENT NOTICE
The ACCUTRON timepiece is manufactured by Bulova
Walch Company, under issued patents as well as pending
paieni applications, including the Following patent*:
O.S,
Canada
France
GemuuT)
Great Britein
SwiUarlaod
Hale
The %Vfir.-) amis
Japan
Z.MO,5*2i 3,971.3211 l.l82.uoe; j,it4.«P.:Re.
».2S7.7&t; 3.221.190; 3.262.259; 1.411.1 ia -i:i H
:
fi76,*17: &09.081; 7M.17B: 756,0ia; 085,410
1.102,373; 74.002: 70,710: 1,401.131:
1.473.153: 1.122,1*3
S71.0SU: 1.096,747; 1,124.413
TBI.009; 797.051: 84D.DH,- BS4.13G;
953.U9; 1,064.230; 1,074,104
112,299; 333.403; 142.171: 301,311
SI7.879; 5M.3.3; 552.IH52; W1JIB: liw.i::
23.037
SO.tSS; 50.196
249,102, 3U1.4&5; 4fl=.52G: 3*0.MS: 2*«,!«'. ;*ft_31
All information contained herein is based on the latest product information a»aitebie at
the lime of printing. The right is reserved lo make changes at any time without notice.
Capjnprt £lft&6. 1969, Baloa Watch Cosipany, Inc. ail "(his reserved.

Table of Contents
Page
To the Watchmaker 2
Part I-SERVICING PROCEDURES 3
Opening the Case 3
Replacing the Power Cell 4
Regulation 5
ACCUTRON" Regulators 5
How to Regulate 6
Removing Movement from Case 7
Replacing Movement in Case 8
Part II -REPAIR OF THE BASIC MOVEMENT 9
Special Tools and Equipment 9
ACCUTRON Service Kit 9
Cleaning Equipment 11
Rate Recorder II
Diagnostic Chart 12-13
Special Points for the ACCUTRON Repairman 14
Indexing Mechanism—Inspection and Adjustment 15
Testing Power Cell 19
Testing Electronic Circuit 19
Identifying Defective Coil Assembly 20
Checking the Train for Freedom 20
Hack Mechanism—Inspection and Adjustment 20
Disassembly _21
Cleaning 30
Lubrication 31
Reassembly 32
Basic Parts List Series 218 40-41
Part III-REPATR OF DATE MECHANISM IN MODEL 218D 42
Removing Hands, Dial, and Hour Wheel 43
Date Mechanism Disassembly 45
Date Mechanism Lubricatinn and Reassembly _. 45
Replacing Hour Wheel. Dial, and Hands 46
Parts List Model 218D 47
Index 48
'"ACCUTRON," -BUIQVA." "VfATCKKASTBr aid "Li" are registered trademarks of Billow Watch Company, Inc.

To The Watchmaker,
This Manual provides complete service and repair information for Scries 218
ACCUTRON movements. Perhaps ynu already have experience in servicing ihe 214
ACCUTRON. Tor which there is aseparate service manual. If so. you will fad thai
while Ihe repair and servicing procedures for 214 and 21 AACCUTRON movements
are basically Ihe same. there are physical differences between (he two. primarily in
the arrangement of parts.
Unlike the 214 ACCUTRON movemenl, Ihe 218 muvemenlN can be repaired and
adjusted wilhnut Oie use of amicroscope. However, those experienced in servicing
ihr /i-i nOVCjeeat (and therefore having aKiutable microscope nvadable). will find
the iniineicope very useful in checking and adjusting 'he 2111 tmli-xinx mechanism.
Even If you have never tmrvlced ACCUTRON. we would like lo poinl out thai the
experienced watchmaker nhoulil ho able lo learn lo service the 210 ACCUTRON
movemenl iu amatter of hour* wilh Ihe aid of this manual. Diagnostic procedures
Tor locating and correcting faults are presented on pages 12 and 13. The firs! step in
using these procedure is lo estuhlish the symptoms of Ihe trouble. In many in
RtanQM Ihin inforiiiatiun cm he obtained only from the customer. Therefore, WHEN
EVER POSSIBLE KIND OUT EXACTLY WHAT THE CUSTOMER'S PROBLEM IS
BEFORE YOU ATTEMPT CORRECTION,
For example, let us assume that an ACCUTRON timepiece has been bronchi In you
because it is gamin*; or Inning lime. You must find out whether the gain or loos in
nfew seconds aday or aminute or more aweek lo determine whether It requires
only simple regulation or whether the movemenl mufil be repaired. Suppose yon
are told only llml "it loses" and your rate recorder indicates aloss of. say. 5seconds
.i day. If you regulate it accordingly nnd return it, you will have avery dissatisfied
customer if ihe timepiece was losing several minutes per day (requiring repair) On
the odicr hand, the timepiece may have been losing several seconds per day, as
shown by your rale recorder, In this case, if you elect to "repair" ihe movemenl. you
are attempting lo locate adefect or fault Ihat does not exist. Such situations can only
he avoided by finding out from the customer the symptoms Ihat led him to bring
the timepiece lo you for correction.

Opening The Case
Use special Inckmy

r
i
Replacing the 218 Power Cell
a. Remove case back, using a
suitable case wrench to unscrew
the locking-ring.
b. Loosen coil lorm screw slightly.
cLoosen cell strap hold-down
screw, swing cell strap out and
remove Power Cell as shown
(see Fig. 3).
d. Remove coil form screw (with
insulator) and cell strap, Inspect
(with loupe) under-surface of cell
strap for foreign matter which
may affect electrical contact with
Power Cell. If necessary, clean
with an eraser and dip-rinse.
e. With the cell strap off. check thai
the insulating posl of the cull coil
assembly hus not been damajtr. 1
through improper installation Of
aPower Cell; attach cell strap
by loosely installing coil form
screw (with its mutilator] through
cell strap, making certain cell
strap is correctly positioned
.imund the insulating post of the
cell coil assembly.
f. Install the Power Cell with
imprinted side down (see Fig. 3);
reposition cell strap under tbt
hold-down screw and sccurr
screws.
g. Check that case gasket is properly
positioned; replace case back
and tighten locking-ring.
Note: If sweep-second hand does
not turn, be sure stem is
in the normal or "in"
position. If so, tap the case
lightly at "3" or "9" to
start tuning fork vibrating.
COIL FORM SCREW WITH INSULATOR POWER CELL
CELL
SIMP
CELL COIL ASSEMBLY
Fig. a

MAY is4 iboy
Regulation
THE BASIC ACCURACY OF THE ACCUTRON TUNING FORK IS SUCH THAT
REGULATION FOR MORE THAN AFEW SECONDS PER DAY IS NOT REQUIRED.
CAINS OR LOSSES OF AMINUTE OR MORE AWEEK INDICATE THE NEED
FOR REPAIR. NOT REGULATION.
ACCUTRON regulators
The ACCUTRON regulators (see Fig. 4Jare serrated to make them easier la rotate
and to serve asacalibration.
G3SERVE THE SEVEN "DMSKWS
Fig. »
The serrations of each regulator form 7divisions (4 projections and 3indentions).
Each of these divisions is equal to 2seconds per day of correction; in other words,
rotating one of the regulators adistance equal to one division, changes the rate of the
ACCUTRON timepiece by 2seconds per day. Regulation for as little as x /x second per
day can be made byrotating one of the regulators V* division. The amount thai aregu-
lator is rotated can be easily gaged by reference to the dot on the top of each cup.
Either one or both of the regulators can be rotated in making acorrection; for exam-
ple, acorrection of 4seconds per day can be made either by rotating one regulator 2
divisions, or by rotating each of the regulators 1division.
Since there are 7divisions on each of the regulators, and since each division is equal
to 2 seconds per day. it would be impossible to make acorrection of more than 28 sec-
onds per day. even if both regulators were originally set all the way in one direction.

How To Regulate
IS
Rotate one or Imlli of the regulators (see Fir. 5)asufficient number of divisions and
in the direction necessary to make ihe required correction. Rotating aregulator away
from the center of the movement will cause the ACCUTRON timepiece to run slower:
rotating aregulator toward the center of the movement will cause it (o run faster.
mHICULAU ?SECONDS PER DAY SLOWER,
MOVE fUMIK REGULATOR ONE DIVISION
OUTWARD AS SHOWN.
TO REGULATE 2SECONDS PfR DAY TASTER,
MOVE EITHER REGULATOR ONE DIVISION
INWARD AS SHOWN
!
Fig. 5

WAY 24 ;3S3
1
Removing Movement
From Case
a. Pull stem oat [setting position].
b. Loosen setting lever screw
2turns. (See Fig. 6.)
cWithdraw stem.
Fig. 6
a. Remove movement from case
and place in movement holder.
b. Insert stem and tighten
setting lever screw.
CAUTION: Do not push
stem beyond point of
engagement with pin on
selling lever. (See
Special Points, item 2,
page 14.]
Fig. 7
IMPORTANT: S« sore To Indicate model number engraved on movoment whan ordering replacement pans

Replacing Movement In Case
r~