This page attempts to explain how to replace the power call in a quartz watch.
The watch shown in the example is a Seiko quartz chrono but the replacement procedure is similar to that used on Citizen, Invicta, Orient, Casio, and many other watch brands.Click the pictures below for a larger view.
Images Comments Tools which are used for opening the case to remove the battery are: A - Universal adjustable screw back tool. Has 3 adjustable prongs which can be made to align with the slots in the screw back.
B - Removable pins for adjustable screw back tool. These are milled to fit the slots in most popular watches.
C - A watch knife (used for removing snap back cases), A strong pen knife may be also used.
Open the brand at the buckle and remove the springbar to separate the band into two pieces. The band does not have to be removed. Use a paintbrush and 'Q" tip to clean out all debris around the screw back.
Start by adjusting the pins in the tool to roughly match the slots in the watch screwback.
As a final adjustment I hold the tool on the watch with one hand while making the final adjustment with the other hand.
NOTE: A light (shining from behind the watch) may be helpful in making sure that all the pins are in the slots.
Once the tool has been adjusted to fit the slots you may begin removal by holding the tool FIRMLY to the watch with one hand while turning carefully with the other. Make sure that the pins do not creep out of the slots or the tool will slip causing the case or back to be gouged.
Once the back starts to turn freely I remove the tool and insert a small screwdriver into one of the slots to complete the turning rapidly.
NOTE: Make sure you pull the crown out to it's second click to stop the watch before removing the battery. With the case back removed the battery can be seen in it's well held down by the retention spring (part of the movement back metal plate).
In the type of movement shown (Seiko) the battery is removed by prying upward on the retention spring and sliding out in the direction indicated. Other types of movements may require removal of a small screw or clip to free the battery. The retention device varies from movement to movement. In the movement shown (Seiko) DO NOT loosen any of the screws in the back metal retainer plate as this may cause problems with the geartrain.
Battery RemovedOnce the battery is out inspect the contacts in the battery well.
If they are corroded clean them with a pencil eraser (it may have to be cut or modified to fit).
Clean out any oils, grease, or debris with a "Q" tip saturated with anhydrous isopropyl alcohol (video tape head cleaner)
Burnish the contacts with a strip of business card until they shine like new.Install the new battery, being careful not to get grease and oils from your fingers on the battery contacts.
Because watch batteries have such low voltages it is important that the contacts be clean and dry.
Resetting the WatchAfter installing the battery most watches will need to be reset to prevent erroneous displays.
In the Seiko model shown the reset is done by taking a small piece of wire and shorting the terminal marked "AC" (All Clear) to the battery "+" terminal for about 5 seconds.
Most watches use a similar procedure to reset. The "AC" marking is stamped in the metal in the back of the movement plate with an arrow pointing to a hole where the wire goes.
Sometimes watches will have reset instructions on a label inside the watch back.
Ready for ReassemblyBefore reassembling the watch back check the following: A - Push the crown in and make sure the watch runs.
B - Check the "O" ring, it should fell soft and rubbery. if it is hard, cracked or torn obtain a replacement.
C - Apply a small amount of silicone grease (Dow Corning 4 or equiv.) to either the "O" ring groove or the land on the screwback and stick the "O" ring to it. Make sure the ring is smoothly run with no kinks or turns.
D - Start the screw back on with your fingers and screw it in all the way using your fingers. Look to see if the "O" ring is not squeezing out of the gap.
E - Once the back is all the way screwed down using hand pressure reinstall the removal tool and give it 1/8 to 1/4 turn extra to seal the back.
