Bulova 100 Meter 98U13 Technical Letter

Watch Setting Guide  

SETTING NON-DATE MODELS

If the watch has no second hand, merely

pull out the crown and proceed to step 2.

Step 1:

When the second hand reaches

the 60th second mark, pull the crown to

the “OUT” position. All hands will stop.

Step 2: 

Turn the hands forward 

(clockwise) to set the time. In order to

prevent the hands from jumping when

the crown is pushed in, set the minute hand approximately 5

minutes ahead of the desired minute marker; then, gently turn

back to the same minute marker.

Step 3:

When the time standard by which you are setting your

watch reaches the 60th second, push the crown to the “IN” 

position without turning. All hands will start instantly.

SETTING DATE AND DAY/DATE MODELS

Step 1:

When the second hand reaches

the 60th second mark, pull the crown

all the way to the “OUT” position

(you will hear two tiny “click”

sounds).  All hands will stop.

Step 2:

With the crown still in the

“OUT” position, move hands forward

(clockwise) until you see the date 

(for date only) or both day and date

change. This establishes midnight.

Step 3:

For AM time, continue to move the hands forward until

the minute hand is approximately 5 minutes ahead of the desired

minute marker; then, gently turn back to the same minute marker.

For PM time, follow the same procedure, but first advance the

hands past 12 o’clock.

Note:

The date will advance automatically at midnight, provided

that AM and PM have been established (steps 2 and 3). The

watch calendar is programmed for a 31-day cycle. Therefore, on

the first day of any month following a month with less than 31

days, the date must be advanced manually (see Step 5).

Step 4:

When the time standard by which you are setting your

watch reaches the 60th second, push the crown all the way to the

“IN” position without turning. All hands will start instantly.

Step 5:

Pull the crown to the “INTERMEDIATE” position 

(one “click”). Your watch will continue to tell time. Slowly turn

crown one way until correct date appears. Then, for day/date

models, slowly turn crown the other way until correct day appears.

Note:

The day is printed in two successive positions on the day

indicator: in English and in Spanish on U.S. models; in English

and in French, depending on the models. It is possible to make

use of either position. The display will automatically remain in

the language chosen. In some models, the calendar cannot be

changed manually between 9:00pm and 6:00am. However, the

mechanism will not be damaged if the crown is turned acciden-

tally during this period of time.

Step 6:

Push the crown to the “IN” position. Your watch is now

operating normally.

HOW TO USE THE ELAPSED TIME INDICATOR

If your watch is equipped with a rotatable outer dial with one-

minute graduations, this can be used in vari-

ous ways to check elapsed time. For example

if a diver has a 30-minute air supply, he can

set the outer ring so that the triangle is in line

with the minute hand when he submerges.

The minute hand will then indicate on the

outer ring the length of time that the diver

has been under water. 

SCREW-DOWN CROWN

If your watch includes a screw-down crown, you have additional

assurance that it will remain watertight. To make the crown 

operational, it must be turned toward you until the threads are

disengaged. Then, instructions for setting must be followed. To

reseal the crown, press in until threads engage. Turn away from

you until tight.

IMPORTANT: Unless the crown is properly resealed, it 

will not be watertight.

******************

IF YOUR NEW WATCH IS A MECHANICAL WATCH

(no battery)

Mechanical watches differ from Quartz watches in several

respects:

1. No battery changes are needed - they are powered by a main-

spring, which is wound either by wrist movement; or in some

models by daily winding of the setting crown.

2. Because it is a mechanical device, it's accuracy is subject to 

the effects of gravity and temperature. You can expect, on the

average, a daily variance of up to 10 to 20 seconds for 

mechanical watches.

3. Just like automobiles, these watches require routine mainte-

nance. Due to their mechanical complexity, mechanical 

watches require cleaning and new lubrication every 3 to 5

years to run at optimum efficiency.

FOR THE AUTOMATIC SELF-WINDING 

MECHANICAL WATCH. 

It must be wound at least six or seven times before you wear it.

After that, your daily activity should wind the watch sufficiently

to keep it running at night when it is not being worn. If your

normal daily activity is not sufficient, occasional supplementary

manual winding may be necessary. It is suggested that your

mechanical watch be cleaned and oiled periodically to insure

optimum performance. As a mechanical watch, quartz watch

accuracy cannot be expected. References to the power cell do 

not apply to Automatic watches.

Technical

Letter

BOOK NO. 63, 11, 448R, 544, 497

, 552        GENERAL

#10828-12/2004

IN POSITION

OUT  POSITION

IN POSITION

OUT 

POSITION

INTERMEDIATE

POSITION