How often, by brand and movement
Each row is what that maker’s own booklet says for the calibre or module named, not a rule for the whole brand. “Overhaul” means taking the movement apart, cleaning it, oiling it and adjusting it; a “check” is a look at the case, crown, buttons and seals.
| Movement | What the maker asks for | Gasket or packing | Who |
|---|---|---|---|
| Seiko automatic, 4R35 family | Overhaul about every 2 to 3 years 1 | Replace gasket and spring bar at the overhaul 1 | The retailer it was bought from 1 |
| Seiko diver’s automatic, 4R35 / 4R36 | Overhaul every 2 to 3 years 7 | Replace gasket and spring bar at the overhaul 7 | The retailer it was bought from 7 |
| Seiko solar diver’s, V131 to V158 | Overhaul about every 3 to 4 years 5 | Replace gasket and push pin at the overhaul 5 | The retailer it was bought from 5 |
| Seiko quartz, 7T32 / 7T92 | Check every 2 to 3 years 3 | The check is to see the case, crowns, buttons, gasket and crystal seal remain intact 8 | An authorized Seiko dealer or service center 3 |
| Citizen automatic, 0200 / 8203 / 8204 / 901x | Disassemble and clean (overhaul) every 2 to 3 years, charge basis 2 9 10 | The packing is a consumable part, replaced as necessary at the inspection 9 | An authorized service center 9 |
| Citizen quartz, 051x | Inspection once every two or three years 11 | Gaskets and other components replaced regularly 11 | Not named in the passage we read |
| Citizen Eco-Drive, B612 and others | Inspection once every two or three years 4 | Packing replaced regularly 4 | An authorized service center, for a charge 12 |
| Casio quartz, module 3529 | No overhaul or check interval published | Gaskets replaced about every two or three years 6 | Original retailer or authorized Casio service center (battery) 6 |
| TMI NH3 series (NH34, NH35, NH36) | No service interval published | Not applicable: a movement, not a case | The technical guide shows oiling spots and a regulator but no owner procedure 13 |
These are recommendations, not wear limits. We found no maker statement that a watch fails on a given day, and none that a longer interval is safe; see what we cannot say. The calibres behind the Seiko rows are on the 4R35 and 4R36 pages, and Citizen’s on 0200 and 8204.
What a service includes
- Seiko overhaul. Washing parts, changing oil, adjusting accuracy, checking functions and replacing consumable parts; the gasket and spring bar are replaced at the same visit. 1 Seiko calls the first overhaul after purchase particularly important. 1
- Citizen overhaul. The watch is disassembled and cleaned. Citizen’s reason is that a mechanical watch can become inaccurate through poor lubrication or worn parts. 2
- Quartz check. Seiko and Citizen describe an inspection of the case, crown, buttons, gasket or packing, not an overhaul. 8 11
- A movement maker’s view. TMI’s NH3 technical guide has an oiling-spot page, so lubrication is part of working on the movement. 13
Seiko does repairs after the guarantee on request and payment, Citizen’s inspection is for a charge, and Casio charges to replace the factory battery even within the warranty. 1 12 6 No price list appeared in any manual or maker page we read, so we give no figure.
Battery: how long, and when to change it
A battery has no single life: it depends on the calibre, the functions used and the cell. The figures below are each booklet’s own, for the movement named. Citizen Eco-Drive and Seiko solar watches are a separate case, covered after the table.
| Movement | Stated battery life | Sign it is running down |
|---|---|---|
| Seiko 7T32 | About 2 years 8 | Small second hand moves every two seconds 8 |
| Seiko 7T92 (diver’s) | About 3 years 3 | Small second hand moves every two seconds 3 |
| Seiko 7T12 | About 5 years 14 | Small second hand moves every two seconds 14 |
| Citizen 051x chronograph | About 2 years (Cal. 051C: 5 years) 11 | Not given in the manual text we read |
| Casio module 3529 | About 5 years, with the alarm and light use the guide states 6 | Large timekeeping error, a dim display or a blank display 6 |
- Change it when it runs out: Seiko says to replace an expired battery as soon as possible, and Casio says running on low power can cause malfunction. 8 6
- Do not leave a dead cell in the watch. Seiko says not to leave a discharged battery inside, and Citizen warns that leaking battery fluid can damage the watch. 3 11
- The factory cell can be short-lived. Seiko says the battery fitted at the factory may last less than the stated period, and Casio calls it a test battery that may go dead sooner. 8 6
- Seiko’s 7T92 booklet says the expected month and year of the first change is inscribed on the case back. 3
- Use the cell the maker names: Casio says to fit only the type in the specifications, and Seiko’s 7T32 booklet names the SR927W and recommends an authorized dealer for the change. 6 8 The cell sizes and the movements that take them are on our SR927SW and CR2016 pages, and the Citizen list.
Eco-Drive and solar. Citizen says an Eco-Drive watch needs no periodical battery replacement and that its special rechargeable cell does not require periodical replacement; it adds that after a number of years power consumption may increase from wear and deteriorating oils, so the stored charge runs down faster. 12 Seiko’s solar diver’s booklet says the same of its secondary battery and that replacing it takes professional knowledge and skill; Casio’s solar guide says never to replace the rechargeable battery yourself. 5 15 Casio adds that after very long use the rechargeable battery may lose its ability to charge fully. 15
Gaskets and water resistance after a battery change
Casio is explicit. Its guide says a trained technician will inspect the watch for proper water resistance whenever the battery is replaced, and tells the owner to ask for the check. 6 It also asks for the gaskets to be replaced about once every two or three years. 6
The Seiko and Citizen booklets we read tie the gasket to the overhaul or inspection every two or three years instead, and say nothing about a water test at a battery change. 1 11 9 We therefore cannot say they require one. Our own caution, not a maker’s rule: until a watch has been checked since its case was last opened, do not rely on the marking on its dial. What the markings mean is in the water-resistance guide.
Can you regulate an automatic watch yourself?
The makers send you to a professional, and none gives an owner procedure. Seiko’s troubleshooting table lists causes to rule out first: a long spell in extreme heat or cold, a knock or active sport, strong magnetism (which needs demagnetization, classed as a repair, and charged even within the guarantee) and more than 3 years without an overhaul. 1 If accuracy does not return after setting the time, Seiko’s remedy is to consult the retailer. 1
Citizen gives its reason: repairs, inspections and adjustments need special technologies and equipment at the service center. 12 Seiko’s 7T92 diver’s booklet says never to attempt to repair a malfunctioning diver’s watch yourself, but to send it to a Seiko Service Center. 3
The movement maker’s papers are the one place a regulator appears. The NH35 technical guide has an “Accuracy adjustment” page marking a regulator (time adjustment) and a stud support (beat error adjustment). 13 It does not say how an owner should use them, and getting to them means opening the case. Whether other calibres, such as the 4R36, have the same adjustment is not in the Seiko booklets we read, so we do not claim it.
What we cannot say
- The Seiko quartz booklets we read (Cal. 7T12, 7T32, 7T92) say to use an authorized dealer for the battery change but do not say that a water-resistance test is part of it.
- The Citizen quartz (Cal. 051x) and Eco-Drive manuals we read name the gasket or packing inspection every two or three years but do not tie a water-resistance test to a battery change.
- The Casio quartz guides we read give a gasket interval and a battery life but no service or overhaul interval for the module.
- TMI’s NH3 technical guide has no service interval; the interval comes from the watch brand.
- No Seiko booklet we read describes an owner adjustment of the rate or says it is forbidden; they send the owner to the retailer.
- No price list for servicing, overhaul or battery replacement was found in the manuals or on the maker pages we read; they say only whether a service is charged.
- We have no source for an interval longer than the makers’, and none that says exactly how far a watch can run past them.
- Only Seiko, Citizen, Casio and one movement maker are covered, and only the calibres and modules named in the table. Orient, Timex, Bulova, Miyota and other makers are not.
- The intervals are recommendations, and nothing here replaces the booklet for your own watch. Seiko’s diver’s booklet adds that the environment a diver’s watch is used in can affect its inner parts and movement as well as its case and band. 7
Found a maker statement that differs? Send it to the corrections page, and see the methodology for how sources are read.