UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Leaking batteries. A reminder, a warning.

Lloyd 1985 · 2nd Jul 2020, 6:50 pm

Another thing to check, watches! Especially, if like me, you have many of them... I’ve just last week discovered a watch that has great sentimental value to me has been destroyed by a leaking 1.5v button cell. I haven’t used the watch for years, and when I got it out of the box I noticed 3 of the glow in the dark blobs on the dial had gone black, as had the silver dial around them. The watch is a Seiko with a screw on back, and the only reason I hadn’t replaced the battery was because I haven’t got the right tool to open it. I’m afraid I went at it with a pair of pliers in the end! I was very careful, and didn’t cause any damage to the back or the case, but once the back was off you could see the damage, the movement has a normally shiny metal plate covering the electronics, this had a black blob in the middle, and the battery was all crusty too, with the same white powdery stuff as mentioned in this thread. I cleaned the contacts and stuck a new battery in, but sadly the watch was dead. I popped the metal plate off the movement, and removed the PCB, which once turned over you could see it was totally encrusted in green crystallised corrosion. The coil looked good, but was open circuit. I cleaned it up as best I could, the coil was rotten where it connects to the main PCB, the corrosion has crept under the epoxy that covers the connections, I managed to repair that, and got continuity back, so that when prodded with the meter the movement would actually tick over! But despite my best efforts with the PCB, I couldn’t get it to run, so I’m now waiting delivery of some old quartz movements to use as spares. Hopefully il get it going again! I have to get it going, it was my Grandads watch that he bought just before he died in 1995, and I’ve had it ever since then, I even wore it to my first job interview (and I got the job!).

I also found leaking batteries in my dads old 1970’s Avia LCD watch, I was able to save that one mostly, but the PCB has become sensitive to moisture! Just the slightest bit of humidity in the air is enough to stop the crystal oscillator running, which has made it kind of useless as a watch, but left with the back open somewhere warm starts it running again.

Regards
Lloyd

2nd Jul 2020, 6:50 pm	#40
Lloyd 1985 Nonode Join Date: Jun 2008 Location: Coningsby, Lincolnshire, UK. Posts: 2,820	Re: A reminder, a warning.. Another thing to check, watches! Especially, if like me, you have many of them... I’ve just last week discovered a watch that has great sentimental value to me has been destroyed by a leaking 1.5v button cell. I haven’t used the watch for years, and when I got it out of the box I noticed 3 of the glow in the dark blobs on the dial had gone black, as had the silver dial around them. The watch is a Seiko with a screw on back, and the only reason I hadn’t replaced the battery was because I haven’t got the right tool to open it. I’m afraid I went at it with a pair of pliers in the end! I was very careful, and didn’t cause any damage to the back or the case, but once the back was off you could see the damage, the movement has a normally shiny metal plate covering the electronics, this had a black blob in the middle, and the battery was all crusty too, with the same white powdery stuff as mentioned in this thread. I cleaned the contacts and stuck a new battery in, but sadly the watch was dead. I popped the metal plate off the movement, and removed the PCB, which once turned over you could see it was totally encrusted in green crystallised corrosion. The coil looked good, but was open circuit. I cleaned it up as best I could, the coil was rotten where it connects to the main PCB, the corrosion has crept under the epoxy that covers the connections, I managed to repair that, and got continuity back, so that when prodded with the meter the movement would actually tick over! But despite my best efforts with the PCB, I couldn’t get it to run, so I’m now waiting delivery of some old quartz movements to use as spares. Hopefully il get it going again! I have to get it going, it was my Grandads watch that he bought just before he died in 1995, and I’ve had it ever since then, I even wore it to my first job interview (and I got the job!). I also found leaking batteries in my dads old 1970’s Avia LCD watch, I was able to save that one mostly, but the PCB has become sensitive to moisture! Just the slightest bit of humidity in the air is enough to stop the crystal oscillator running, which has made it kind of useless as a watch, but left with the back open somewhere warm starts it running again. Regards Lloyd