Day 'N Date 4000
1971 · 10k Yellow Gold Filled · Automatic
About the Day 'N Date 4000
Made from 1971 through 1971, the Day 'N Date 4000 is part of Hamilton's Day 'N Date family, a line built around the practical appeal of having both the day and date displayed on the dial. The case is 10K yellow Gold Filled, and the movement is automatic. The hooded lugs give the case a distinctive silhouette that was very much of its era.
Finding a clean example means paying close attention to the Gold Filled case, which can show wear through to the base metal at the lugs and high-contact points after fifty-plus years. Gold Filled cases are durable but not immune to time, and the condition of the finish tells you a lot about how the watch was treated. The hooded lug design also tends to accumulate grime in the recesses, so a close look there is worth the effort.
Hamilton Catalog Images
1971
What to Look For
| Dial | Look for fading, spotting, or discoloration around the day and date windows, which are common failure points on dials this age. Any moisture intrusion tends to show up first near the apertures. |
| Crystal | Check for deep scratches or crazing. A fogged or yellowed crystal can sometimes be replaced, but confirm the profile matches before assuming a standard replacement will fit. |
| Movement | Dried lubricants are a real concern in any automatic that has been sitting unworn. If the rotor spins but the watch won't run, or runs erratically, a service is needed before regular wear. |
| Case | Inspect the lugs and caseback edge closely for wear-through on the gold fill. Some surface wear is expected on a watch this age, but deep wear exposing base metal at the lugs affects both appearance and value. |
| Crown | Cycle through winding and the day and date setting positions. Both complications should advance cleanly. A crown that feels loose or skips positions is a sign the stem or setting mechanism needs attention. |
The Movement
The Day 'N Date 4000 runs on an automatic movement driving both a date and a day display. Automatics from this period rely on a rotor that winds the mainspring through wrist movement, so a watch that has been stored for years may need a service before it runs reliably. Dried oil creates enough friction to degrade timekeeping or stop the movement entirely, and a full service restores both function and longevity.