VDO Kienzle clock... run time per winding? - PeachParts Mercedes-Benz Forum

Shortsguy1 · #1 01-07-2015, 06:28 PM

Hello-
I am considering to tackle the repair of my w115's VDO Kienzle clock. It is a mechanical clock which uses 12V to self wind itself. I have also removed one from a parts car and it appears that someone has already fixed it. After a cleaning, I was able to get it to run. But I noticed that the clock from the parts car re-winds itself very frequently. I thought I read elsewhere that they run for a couple of minutes between windings, but this clock winds itself every 47 seconds. If you can hear your clock wind, could you check how frequently your clock re-winds itself? (I have never had a running clock installed, so I don't actually know if it is possible to hear it click). Anyway, if 47 seconds is in the ballpark, I will probably just swap out this parts car clock into my vehicle. Thanks.

JeffreyNMemphis · #2 01-08-2015, 08:36 AM

Does the clock keep accurate time? If yes, that would be enough to make me happy. I remember hearing my clock make noise regularly. At that time, I did not understand clock movements. Now I know that electro-mechanical is wound and Quartz is continuous electric. I am generally going to choose the original type that came from the factory and celebrate the oddness of that period technology.

Do you have a picture? We love pictures!

ejboyd5 · #3 01-08-2015, 08:53 AM

As stated above, not to worry about rewind time, the most important thing is the accuracy of the instrument. So far as my experience goes, each clock will have its own "recycle" time depending on how it is assembled, lubrication of parts, etc. Just for a point of reference, I timed a VDO clock from a 911 that is lying on my bench - 2 minutes, 22 seconds between rewinds. Nothing else close at hand to time and it's too cold to walk to the garage.

Tomguy · #4 01-08-2015, 12:38 PM

Right, the frequency of winding has no impact on accuracy. The accuracy will depend on internal cleanliness and lube. It's possible cleaning it may make the winding last longer simply because it winds more? I am unsure, since I don't have one on hand to examine how it works.

Shortsguy1 · #5 01-08-2015, 01:07 PM

Thanks everyone. Perhaps my question seems nitpicky, but I was thinking that if the clock is rewinding too frequently, perhaps it will break again sooner (more "fatigue").

Yes, I have it hooked up to a power supply at 12.5V, and have been adjusting the knob on the back to get it to read the correct time. It was about 5 minutes slow per day, but now I have it correct to within a minute after many days. For kicks, I have now changed the power supply voltage to 13.5 to see if that makes a difference. That test is on-going.

The article at the link below says to clean the clock mechanism with soap/water and the lubricate the bearings with fine clock oil. It then goes on to say to NOT lubricate the "jewelled balance-wheel bearings". Can anyone help me understand which those bearings are? I don't want to lube the wrong things.
1972 VDO Kienzle Clock - Mercedes-Benz Forum

Shortsguy1 · #6 01-08-2015, 01:11 PM

Never mind about my question regarding the balance wheel bearings. Wikipedia to the rescue:
Balance wheel - Wikipedia, the free encyclopedia

Tomguy · #7 01-08-2015, 03:21 PM

I always found the clock kept time differently in the summer than the winter, but of course, YMMV if the clock is cleaned and properly lubed. Mine almost surely wasn't!

ScooterABC · #8 01-09-2015, 08:57 AM

The clock accuracy is going to depend on temperature, as the clock spring is going to have different tension (and a different rate) based on temperature.

Changing the voltage should have no effect since all the voltage is doing is winding it when it needs to be wound. It is not powering a motor.

Shortsguy1 · #9 01-09-2015, 12:49 PM

Quote:

Originally Posted by ScooterABC

Changing the voltage should have no effect since all the voltage is doing is winding it when it needs to be wound. It is not powering a motor.

ScooterABC is correct. I just checked my experiment and raising the power supply to 13.5V did not change the timing of the clock.

I am now going to clean and lube this clock to see if that makes a difference to its ability to keep time. I plan to use soap and water to clean per that article I linked to above and I plan to lube it with some very thin synthetic oil that I have for my mountain bike suspension fork. My hypothesis is that the clock will run faster after this, but we shall see.

Rick76 · #10 01-09-2015, 01:37 PM

What condition are the contacts in?
There is a considerable arc across the contacts each time the clock winds and this eventually burns the contacts and causes loss of material.
They can be cleaned up with some 600 or finer grit sandpaper and then by adding a diode across the coil, the arc can be dramatically reduced. The diode gives a path for the energy generated by the collapsing magnetic field in the coil.
There are special diodes for this application but the common 1N4007 will work fine. Anode of diode goes to negative side of coil and the cathode goes to the positive side (indicated by the band on the diode).

Shortsguy1 · #11 01-09-2015, 02:19 PM

Yes, I cleaned up the contacts previously. The clock was somewhat running when I pulled it from a parts car, but wouldn't make a decent connection when wound down. Smoothing those contacts fixed that problem.

The previous owner has already installed a diode, which is why I am leaning towards using this clock.

Today I cleaned the clock in soapy water and lots of little chunks of dirt came off. I then rinsed it in clean water and dried it gently with a warm-ish hair dryer. I lubricated every bearing that I could reach with a toothpick and Redline Synthetic 5wt suspension fluid, except for the balance wheel bearings which I left un-lubricated.

I will post back when I know if the clock is keeping the same time before, or perhaps it runs faster now that it is cleaner and lubed.

Thanks everyone again for your thoughtful suggestions.

Shortsguy1 · #12 01-12-2015, 04:31 PM

So upon further inspection, it appears at a PO adjusted the location of the stationary contact to put it closer to the other, moving contact. The stationary contact is on a long arm, and they wedged it in a way to shift it over a little. Not sure why, but I removed the piece of paper they used to wedge it over. The clock seems to run fine and now it takes approximately 2 minutes between winds. This sounds more typical based on others' experiences.

Cleaning and lubing the clock did not change the clocks ability to keep time. It seems to get off about 1 minute per day, but maybe I just need to accept it.

Marrs · #13 01-12-2015, 09:10 PM

Quote:

Originally Posted by Shortsguy1

Cleaning and lubing the clock did not change the clocks ability to keep time. It seems to get off about 1 minute per day, but maybe I just need to accept it.

My W111 clock (and nearly all clocks) has a +/- adjustment lever on the back to fine tune the accuracy, moving the lever towards "+" makes a slow clock faster and "-" makes a fast clock slower. You can adjust then wait at least 24-hrs before comparing to something electronic for known accuracy, but I recommend 48hrs or more for better accuracy, then adjust again until you hit the sweet spot. Also, In addition to temperature affecting the clock's accuracy due to the spring expansion/contraction, (no longer an issue with modern metallurgy) as ScooterABC suggested, the oils used can get thick in cold weather if of the wrong type and cause binding or slowed mechanisms.

Jub · #14 01-15-2015, 07:53 PM

Marrs,

My clock is always off ~4 min every week.

So you can adjust it (does your clock look like mine; attached).

Thanks,

Jub

Marrs · #15 01-15-2015, 08:16 PM

Quote:

Originally Posted by Jub

Marrs,

My clock is always off ~4 min every week.

So you can adjust it (does your clock look like mine; attached).

Thanks,

Jub

Hi, no my clock is much different. Here is pic of similar found online:

You should still be able to adjust your clock however. On this the there is often a small paper ordeal covering the adjustment hole. You should not need to take the clock apart to find this, just look on the back and peel it off. From there you typically use a very small jeweler's flat tip screwdriver or similar to turn one way or the other. Some clocks use levers, but I doubt your does. As a guide, a slow clock (as with a wrist watch) generally means it needs to be cleaned. "Cleaning" in the horological world means removing, taking the gears out and apart, sonic cleaning bath to remove old oil and debris, then reassembly, replace worn or broken parts, and re-oil with the correct grades oil for each spot needed. On purely mechanical or electro-mechanical clocks like in my car you can safely do this type of cleaning yourself, but you must take care with a quartz clock (as I believe yours is) to not get the electronics wet. For the record, a watch or clock that is running too fast usually means it has become magnetized and needs to be demagnetized to run on time again. This happens more to watches simply because they are on our arms and come into close contact with magnetic fields more often. For the tech nerds out there still reading, some watches like my IWC Fliegerchronograph use a soft iron shield to protect the mechanism from such magnetic field disruptions, since accuracy is very important if you're using the watch to navigate by (which almost nobody actually does anymore).