911 Clock Swap/Repair/Upgrade

[RNajarian]

To anyone interested. . . :

I’m doing a project to get my Targa’s clock working again. Rather than repairing it I am replacing the internals with a battery operated clock.

This is a “I wonder if I could do this project” because I already have three other working 911 clocks.

1) I am aware of mingmong’s thread to replace the defective capacitors in our OEM clocks.

https://forums.pelicanparts.com/porsche-911-technical-forum/913721-vdo-clock-repair-incl-pictures.html

2) I already have four spare OEM 911 clocks. Three are used but work. I bought them when 911 gauges were cheap. One purchased in 2007 for $50, one purchased for $100 in 2012, and one purchased in a lot of gauges also in 2012 for $125. The last one doesn’t work, I attempted mingmong’s repair but no luck, it still doesn’t work.


. . . with that being said this is what I did with my non-functioning clock inside my car.


I’ll admit, I had some dumb blind “you gotta be kidding me” luck in this project. Look for the instances of luck highlighted in gold. You will see where my luck ran out in red.


Here is a photo of the non working OEM clock.


Here is a 3” battery operated clock I found on Amazon shown with the case of the OEM clock.


Same clock dissembled


Blind luck event #1:Can you believe the shaft of the donor clock fit the face of the OEM clock face perfectly?


Blind luck event #2: Can you believe the donor clock mechanism/gear box fit perfectly inside the OEM case without modification?


Blind luck event #3: Can you believe wire used to relocate the clock’s battery snugly fit into this grounding hole in the OEM clock body preventing stress on the soldered connections? (See screwdriver)


I painted the donor clock hour/minute hands orange. According to a thread here on Pelican the closest color match to the OEM gauge needles is Testors Model Masters 28915, which, of course is out of production. I mixed a little red with orange to get a relatively close match to the OEM needle color. Unfortunately the OEM hour/minute hands did not fit the shaft of the donor clock.

I painted the sweeping second hand of the donor clock white, to replicate the white elapsed time monitor needle found in the OEM clocks.


Blind luck event #4: The 3” flat glass from the donor clock fit perfectly into the black bezel of the OEM clock. Unfortunately I dropped the glass and broke it. I ordered a piece of flat 3” acrylic to replace the front glass of the clock.

I got lucky with a few elements of my project but my luck ran out with this one. . . when the clock needs to be reset for daylight savings time or a dead battery I will not have access to change the time since the mechanism is sealed inside the clock. I will try and figure out a way to address that, if not, a clock still tells the correct time twice a day . . . I may have to wait till the correct time of day to install fresh batteries.

I’ll post a photo of the finished clock once the 3” acrylic arrives from Amazon.

The best part of this project is if it ends up looking terrible I have three OEM spares I can use. Nevertheless, my project seems to be an inexpensive reasonable repair for the inoperative 911 clock.

Thanks for listening.

EDIT:

Here is a photo with the second hand and bezel in place (without the glass)

[snbush67]

Fun simple project. I kept the second hand active and used the stock clock hands.

[EC900]

Nice job.
I contemplated the same retrofit of a battery-operated quartz lock unit too when my 911clock was inoperative but located the electric gremlin and the original still working. I did use a quartz unit to retrofit and old 120v warehouse wall clock and got lucky that the original hands all fit.

For the back side of the clock housing, drilling a small hole (bit larger than a pencil/eraser) just enough to reach in to twist and turn the adjuster wheel, or even smaller like the size of a pick that could work a few rotations to change time.
One word of note, I never like to rotate any mechanical clock backwards (or an engine). I’m no clockmaker but rather not take a chance jumping or ruining gear...even on a $3 clock mechanism.

Good work RN…I salute your craftiness ! Thanks for sharing !

[EC900]

Nice work SN !
My original makes the ticking sound, does either one of you have the same or are these silent? I have a wall clock that makes the ticking and another that’s silent.

[RNajarian]

Originally Posted by EC900

Nice work SN !
My original makes the ticking sound, does either one of you have the same or are these silent? I have a wall clock that makes the ticking and another that’s silent.

The OEM units I have are silent. No ticking

[snbush67]

I don’t hear any ticking on my clock.

[almostordinary]

Originally Posted by snbush67

I don’t hear any ticking on my clock.

I just did the capasitor fix on my 87 clock and actually bought all the stuff the OP mentioned in the hope to find a simple solution.

Everyone said their clocks made noise, I bench tested and nothing.

Well I just went back and bench tested and can confirm my clock works w the capasitor change. There's a small metal wheel that is the time keeping mechanism and it's turning! No Noise.

whew! time to put this back together and call this a W!

[RNajarian]

Originally Posted by almostordinary

I just did the capasitor fix on my 87 clock and actually bought all the stuff the OP mentioned in the hope to find a simple solution.

Everyone said their clocks made noise, I bench tested and nothing.

Well I just went back and bench tested and can confirm my clock works w the capasitor change. There's a small metal wheel that is the time keeping mechanism and it's turning! No Noise.

whew! time to put this back together and call this a W!

You are a better man than me!

[grb008]

I kind of lucked out but keep your eye's open. I purchased replacement quartz insides for the clock from a guy selling the insides from older European trains. Something to keep an eye open as the trains used the same clock insides. It was a direct fit.