350SL Clock Repair

[Mesquite Star]

I have a 1972 350SL with a clock that doesn't work. It is a VDO Kienzle clock and has a white plastic cover on the back.
I can not remove the white plastic cover, even after removing the two nuts from the threaded screws.
Is there a special process for accessing the working parts of this clock?
Any and all advice will be greatly appreciated.

Thanks,
Bob

[meltedpanda]

its not easy, if you have the type that does not come apart with the rear nuts removed then you have to pry the silver ring off and it is easy to damage the trim ring. The mechanism is inside a metal can, with the front chrome bezel crimped over the rim to seal it in place. You have to carefully pry the chrome bezel from ithe can with a thin tool, trying not to damage the chrome. Then, after the clock is repaired AND tested, the bezel can be worked back into place. I was suprised my 73 had this style as well as I thought this type enclosure only started in later models.

[donbryce]

Here's a good how-to on this subject http://www.drivewerks.com/tech/mult_vdo_clock_repair.htm
I fixed my VDO clock last week, the type that is in the instrument cluster, under the tach. The top post had broken off one of the main gear assemblies, so it was wobbling around and very hard to set with the knob. I drilled out the four plastic 'seals' on the posts, on two clocks, and robbed the gear assembly from a non-working one into mine, then drilled tiny holes and reassembled with screws.
I should do how-to on this, as the threads in the DIY section don't really address repair procedures, but I'm getting a little discouraged with the responses I'm getting.

[Mesquite Star]

meltedpanda & donbryce,

Thank you for the information. I will let you know if I am successful.
donbryce, I think that would be a good idea to do a How-To-Do Repair Procedures on clock repair, I'm sure there would be many grateful would-be clock repairmen.

Bob

[Mesquite Star]

meltedpanda,

I pried off the metal ring and removed the bezel and glass, but still could not get to the clock works, the clock hands and face would not come off of the shaft and would not allow it to be pulled out the rear and the white rear cover (where the clock works are) still would not come off even with the two nuts removed. Looks like it was made to not be disassembled. Thanks anyway.

Bob

[Gurunutkins]

HI Bob
I dont know mif mine is the same as yours, I have a 74 450sl. the only way I could get mine apart was to pull off the little copper ring on the white rear cover. It carries the earth for the clock. the white cover then came off easily and I soldered on a new connection when i fixed the workings (they just basically needed cleaning and oiling)
dont know if yours will be the same or not
cheers
barri

[Mesquite Star]

barri,
Thanks for your suggestion, but my clock does not have a little copper ring on the white rear cover. It has two threaded screws with very small nuts, four pins protruding approx 1/2 inch, one is a guide pin, one is a ground (earth), and the other two receive 12 Volts from the plug. I think one of the pins provides 12 volts for the light inside the clock and the other pin provides 12 volts for the clock mechanism.

Bob

[meltedpanda]

Originally Posted by Mesquite Star

meltedpanda,

I pried off the metal ring and removed the bezel and glass, but still could not get to the clock works, the clock hands and face would not come off of the shaft and would not allow it to be pulled out the rear and the white rear cover (where the clock works are) still would not come off even with the two nuts removed. Looks like it was made to not be disassembled. Thanks anyway.

Bob

Wow, that is amazing, gotta come apart somehow, can you remove the hands, face?

[Mesquite Star]

meltedpanda,
No, I cannot remove the hands and face. The little brass button with a cross on it for setting the correct time will not come off of the shaft, so the hands and face cannot come off.

Bob

[meltedpanda]

any chance to post a picture (s)

[Strife]

Hmmm...if it's the same construction as the temperature gauge that later replaced the clock in this spot, afrer removing the aluminum ring from the front (not easy to do without damage) and the gasket and glass, there should be two nuts on the back of the "pod" that should come off, and then the "guts" (including face) should slide out. I did this successfully three times on temperature gauges where I repainted the needles.

Have you tried to push (maybe on a block of wood) on the two threaded studs exposed on the back afrer removing the nuts? Maybe the mechanism is in there tight.

[Mesquite Star]

meltedpanda,

The attachments are two photos of the clock

Thanks,
Bob

[Mesquite Star]

Strife,

Yes, I have tried to push on the two threaded studs after removing the nuts, I have tapped on them lightly, not enough to damage the threads, but there seems to be something that is holding the white case onto the clock works. I am unable to determine just what it is. There is one thing that I do not know just what it is, and that is the round (approx. 1/4 inch) object that is in the upper left of the photo that I just posted. It is surrounded by a plastic ring which I cracked by prying on it, but it did not come loose.

Bob

[meltedpanda]

Bob,
Do you think this has been off in the past, any indications someone has been it it before you, I am thinking perhaps someone glued it ?
I see no reason with what you have said and by looking at the pictures that it should not come apart.

[Mesquite Star]

meltedpanda,

No, I do not think that it has ever been taken apart.
However, after deciding to try everything to get the white cover off, I broke the round plastic cover (in the upper left corner of the photo) under which I found a third threaded stud with a nut on it. After removing that nut I could then take the white cover off.
But, I still cannot get the hands and face off after uncrimping the bezel ring and I need to get them off so I can get inside that metal housing and re-attach the light bulb holder that I caused to come loose while trying to remove the white back cover.

Thanks,
Bob