Every Z owners fantasy.....a working Clock

[Phil Z]

My Z about a week old.

I recently purchased a complete set of used gauges. My gauges, actually my oil & temp gauge was fluctuating after I thought I had solved the problem. So I removed my 46 year old gauge and installed a 46 year old gauge. Much to my surprise upon trying the oil & temp gauge, it worked perfectly. Then I tried hooking up the clock. It didn’t work. Because I have a functioning clock that I built I had nothing to loose and opened it up. I hooked a 9 volt battery to it and watched as the motor tried to wind the spring but it seemed weak. I tried it on 12v from the car. It acted the same. I removed the motor (simple to do) then carefully wound the gear the motor was supposed to wind. It started ticking, a good sign. Decided to spray the clock gears with 3n1 penetrating spray to get gunk off of the gears. Tried the motor again with the same results. Decided to take the brush assembly out of the motor. I didn’t see anything wacky but wondered if the motor was just tired. When the motor was operating outside of the clock, it ran well. Looking at the brushes and armature I could see there wasn’t noticeable wear. Thinking through how electricity works best, I took the brushes out and bent them closer together. Inserted the brush assembly back together and ran the motor. It seemed stronger. I attached the motor back into place. Using the 9v battery the motor was able to wind the main spring. That’s when the magic happened. Tick tick tick, a working original clock. I would have made a video of the motor repair but I would have had to bleep every other word. If anyone wants to tackle this motor fix I can help you do it bleep free. I am not guaranteeing your clock will work but it might. 1972 clock probably built early 1971.

 

 

Phil Smith

[psdenno]

Congrats on the fix!  A working clock is still on my getting longer every day "To Do" list.

Dennis

 

 

[siteunseen]

That's great!

My barrel list too, someday. 8^)

[rcb280z]

On my list as well! Will take you up on the offer when I'm ready.

[Phil Z]

On my list as well! Will take you up on the offer when I'm ready.

I don’t know if what I did to my 240z clock applies to a 280z clock unless you also have a 240z clock.


Phil Smith

[rcb280z]

Phil, I'm not sure what the differences are but I will check.

[Dave WM]

if its a 280z with the transistor oscillator and coil to energize the balance wheel, then its prob the coupling cap, a small 5uf IIRC that most likely has dried up losing the ability drive the coil.

[rcb280z]

8 minutes ago, Dave WM said:

a small 5uf

Is this readily available and easy to replace?

[Dave WM]

yes and yes. My only suggestion is you do NOT unsolder from the bottom of the pcb, rather just clip the old out from the top, and pig tail the new to the stubs of the old cap. the reason being the coil wires that attach to the bottom of the pcb are VERY thin, as in HAIR  thin, you run the very real risk of breaking something. The correct thing to do would be to use an ESR meter on the cap to confirm its status, but I would bet its the issue. there is a smaller cap 1uf that I do not think is the problem, but any electrolytic cap that is 40 years old is way past normal service life. It would be good if you had some PCB solder experience and a proper solder iron (NOT GUN) to do this kind of work.

 

[Zed Head]

I fixed the power supply on my computer by replacing a capacitor.  They tend to leak brown goo at the top when they go bad, if I recall right.  Used it as a reason to buy a nice Hakko FX-888 soldering iron.  On sale at Fryes.  Enough power to desolder and a digital temperature setting.  Much better than the old wood burner I learned on.

 

[Phil Z]

yes and yes. My only suggestion is you do NOT unsolder from the bottom of the pcb, rather just clip the old out from the top, and pig tail the new to the stubs of the old cap. the reason being the coil wires that attach to the bottom of the pcb are VERY thin, as in HAIR  thin, you run the very real risk of breaking something. The correct thing to do would be to use an ESR meter on the cap to confirm its status, but I would bet its the issue. there is a smaller cap 1uf that I do not think is the problem, but any electrolytic cap that is 40 years old is way past normal service life. It would be good if you had some PCB solder experience and a proper solder iron (NOT GUN) to do this kind of work.
 

Did you get that clock working? You said part 2. Are you aware of zclocks.com. I have a possible 260z clock works that is quartz also but it doesn’t look like the one in your video. The back of the clock housing is stamped KS Kanto Seiki. The clock mount doesn’t use a screw. It seems to wedge into place. clock works mount bracket
This one was not keeping accurate time and I replaced the one capacitor that it had. No adjustment screw for speed.


Phil Smith

[Dave WM]

ugh quartz, I see an IC in there too. Yea I got mine working in part 3 of the video, keeps great time too! anyway if the Q style is not working and you replaced the one cap, just a guess, the Xtl is bad, that is assuming the coil and mech parts are ok. Zclocks I am sure is all over this, I only have exp with the one type in the video, but I do know that Xtl's can go bad. I have worked on old color TV sets that need a Xtl to run an internal osc at a very precise freq to demodulate the color signal in color broadcast. Uses a reference signal on the back of the horz sync pulse to set up the phase  and then uses  phase modulation (comparing the phase of the signal during the scan to the ref phase that is maintained by the internal osc), really neat stuff since the engineers figured out a way to get a color signal what works with old B&W sets (reverse compatible) back then that was important considering how many tvs were fielded and not cheap like todays stuff. Anyway back to the Xtl, on the color sets it would become unreliable and not hold the freq, the result was a vert rainbow pattern in the picture rather than a nice color picture. I think it could have to do with how the set was stored, most likely a humidity factor, that would mess up the quartz. IC's are silicon based potted and VERY reliable so that pretty much means it has to be the Xtl.