Trying My Luck - Clock - Can it be Fixed?

[meltedpanda]

Now that I successfully rebuilt my gas gauge, (thanks Bill) I am onto the clock. I got it out of the dash and seems to be quite a clock, surely it can be rebuilt.
I checked the archives but I am not sure they are talking about the same model
Mine is a VDO 12V 0202 I think?

[kpb]

Geez, ron, the CLOCK?!?!?!

[mzsmbs]

http://64.233.161.104/search?q=cache:JkK6qkh28BAJ:business.baylor.edu/Richard_Easley/autofaqs/clock.htm+Richard_Easley/autofaqs/clock&hl=en&client=firefox-a


actually before it dis-appears again let's quote the whole thing here.

Clock Repair Procedure

for Mercedes-Benz Automobiles


Introduction

Most later model Mercedes-Benz clock failures are due to a bad capacitor (or capacitors) on the back of the clock. Removal of the instrument cluster to gain access to the clock is a simple process with the use of two special tools that can be made from common household items. You do not have to be an electrical engineer to do this procedure. The electronics on the clock consist of only 4 or 5 components, so identification is easy.

Tools needed for repairing late model Mercedes-Benz clocks

• 1. High powered flashlight or shoplight.
• 2. A small low-wattage soldering iron.
• 3. De-soldering tool (not mandatory, but nice).
• 4. Rosin-core solder.
• 5. A miniature screwdriver set (flat blade).
• 6. Meguiar's Plastic Cleaner.
• 7. Meguiar's Plastic Conditioner.
• 8. Dash removal tool (Special tool: handmade). To make, fashion a non-OEM factory instrument panel tool out of a a thin coat hangar by doing the following: a. cut the long bottom strip to use as the tool. b. put a 75 degree bend at one end with a couple of inches of extra wire. c. cut the bent wire about 1/4 inch from the bend with a pair of wire cutter and leave a "sharp" edge with the cut. At the other end of the coat hanger, fashion a circular handle out of the excess, leaving the whole tool around 4-6" in length.

Parts needed for repairing late model Mercedes-Benz clocks

1. Radio Shack part number 272-1028. You will need two of these capacitors, and they only cost around $1.00 each. These are the only parts needed.

Instructions

• 1. If your car has a telescoping steering wheel, fully extend the wheel (as far away from the dash as possible). (If it doesn't have this feature, you can still probably do this without removing the steering wheel by judicious wiggling.)
• 2. Using your instrument panel (IP) removing tool (which you built with pride), slide the tool in between the IP and the left side of the dashboard at the 10 o'clock position, with the hook facing down and parallel to the side of the instrument cluster. Push the tool all of the way in. Turn it 90 degrees to the right so that it engages the instrument panel. Grabbing the tool's handle, pull the left side of the IP out carefully, until the tool's hook just clears the dashboard.
• 3. Repeat step 2 on the right side at the 2 o'clock position.
• 4. Put a large clean towel on your workbench.
• 5. You should now be able to grab the IP by hand. Pull it out at the right.
• 6. Start unplugging things. If the oil pressure gauge has a "live" oil line, unscrew it and cover the open line with a piece of rubber-banded plastic. You'll want to mark the bulb assemblies with numbers if they are not already marked (mine were -- I'm not sure if from factory or not.). Unplug everything.
• 7. Remove the IP from the car to your bench.
• 8. Lay the IP face down and carefully note ordering of instrument "pods." Mine had three.
• 9. Remove the pods carefully and place in a non-scratchable location.
• 10. Using the Meguiar's products, clean and condition both the inside and outside "glass." It'll take a while, but you'll be pleased with the result. Somehow, the inside glass accumulates dirt over time.
• 11. Plug in the soldering iron to let it warm up.
• 12. Now, to the clock. The clock's hands remove easily with your fingers (notation of positioning is unimportant at this point), but the tachometer's needle is better left alone.
• 13. Remove the three flat screws on the front of the combo which hold the tachometer to the instrument facing.
• 14. Put the combo face down on the towel.
• 15. Remove the rear screws which hold the tach and the clock.
• 16. After removal, you should now be able to separate the combo enough to remove the clock as a component to work on.
• 17. Don't forget to "save" the rubber gasket on the back of the clock for installation at the proper time.
• 18. Place the clock face down on the towel. Find the capacitor(s). They are about 1/2 inch long and round. (the only other electrical components are: 1 resistor, a crystal, and an integrated circuit).
• 19. Note the direction of the capacitors (there should be a "+" on one end.)
• 20. Using the soldering iron, and a large miniature screwdriver for leverage, "de-solder" the capacitor (or capacitors), placing the screwdriver blade between the capacitor and the circuit board for leverage. You'll have to do this in stair-step fashion, since the solder will probably harden before you can remove the whole thing at once. After removal of the capacitors, "clean" the wire holes by heating the solder and shaking it off. (Note: a "desoldering" tool will work more effectively during this step, but it is not mandatory.)
• 21. Install the new capacitor(s), without cutting their "leads." Note that the Radio Shack replacements have a "-" instead of a positive marking direction.
• 22. Cut the leads at the edge of the solder joint.
• 23. Reassemble and reinstall everything.
• 24. When putting the clock the clock hands back on, align them both at 12 o'clock.
• 25. Turn the hands for a few revolutions using the setting knob and align as necessary.
• 26. Finally, let me know if you complete this procedure successfully; it took a while to type this, and I'd appreciate knowing when each person has completed the repair! Please e-mail me at richard_easley@baylor.edu

[300SDog]

Yeah, MZ nailed it..... the quartz clock on 115's has internal fuse as opposed to earlier models (111/110 etc) that have external fuse - a chunk of solder on the outside. Gotta believe there's nothing wrong with the clock at all, fuse has probably corroded over time that's all.

LOL, gotta tear into the clock innards and/or subcontract the work to Radio Shack or somebody who knows how to solder... thats all.

[mzsmbs]

oh heck, here is another little description: (this is something i need to do this winter also)

It's not at all difficult. Success will depend on how many hours the
movement had on it when it stopped. Pull out the instrument cluster, spin
off the two finger-screws that hold the clock to the circuit board, and pull
it out front.

Make note of the condition of the white plastic clock case. Does it have a
blue plastic lock on one of the nuts? If so, then it hasn't been worked on.
Does it have a paper tape over the adjust hole? If so, it probably hasn't
been adjusted.

Break off the seal with small diagonal pliers, then remove the nuts with a
4.5mm nut driver. Pull off the case. The fuse is probably gone. Look for
a tiny blob of metal rolling around. If it's not rolling around, then it
may be jammed in the gearwork somewhere, and it must be found. The fuse is
normally located on one side of the solenoid. One of its electrodes will
have sprung away, and now lies against the phenolic back-plate. You will
see the holes in this and the stationary electrodes where the fuse/rivet was
installed.

Spring the bronze piece back so that the two holes match. While maintaining
tension on this spring, heat the junction with a soldering iron, and
introduce a little bit of tin/lead solder, sticking together the two metal
electrodes and establishing a conducting path.

Clean the soot out of the inside of the case, just to be neat. Use a
relay-contact burnisher on the points, or use a small bit of 600-grit emery
paper. Note that when you put a little force on the flywheel (where half of
the points is) the clock should start smartly and begin running. You can
cock the winder manually with a little flick of the flywheel (clockwise, if
you are looking toward the back of the clock) and watch it run until the
points touch.

Put a tiny, tiny bit of clock-oil in the bearings, front and back, of the
first and second wheels. Don't have any clock oil? Go to a good hobby shop
and get some German N-gauge (MiniTrix) or Z-gauge (Maerklin) model train
oil. It will do in a pinch. Try rocking the wheels to determine the
condition of the bearings. There should be no noticeable play. "First and
second wheels" are the wheel that contacts the winding flywheel (shafted to
the phenolic plate) by way of a pawl and the next wheel in the gear-train.
If the back bearings for these wheels are shot, then the clock will not
start spontaneously nor run freely.

Do not get near this clock with WD-40. WD-40 has its place, but that place
is not on the same bench with a clock.

Connect the clock to a 12-volt supply and observe its running. Set it. Let
it run overnight. Note the time, and adjust as appropriate. Adjustment is
a gradual, subtle procedure, and should never be rushed. Don't expect too
much accuracy from such a simple movement.

That's the minimum clock service. If anything else is wrong, then the
movement has to be taken apart, and that's another story.

[meltedpanda]

Originally Posted by kpb

Geez, ron, the CLOCK?!?!?!

That way I know how many hours I got in this daggone car

[meltedpanda]

mzsmbs, thanks, your description fit my model, found the issue and fixed it. Works on the bench, may be months before it finds its way back to the dash!

[trainman715]

Thanks for the info. The repair worked perfectly on my wifes 1985 300SD. I had the instrument cluster out looking for the cruise control speed transducer. Thought I may as well dive into the clock while I was at it. Only took about an hour after the instrument cluster was on the bench. After taking the 3 screws out that hold the tack face plate on, I removed the 3 screws on the back that hold the tack to the mounting plate. This gave me more room to get the clock out without removing the tack pointer. One other thing....The clock has a solder joint on the mounting plate. That is where the clock gets it ground. You have to unsolder this to remove the clock. I still have not found cruise control speed transducer...Where is it??
Roger

[gdemoss01]

It is pluuged into the back of the speedometer, almost cube-shaped, black plastic cover, about 1" square.

Rev. Dr. G.

[250 Coupe]

Completly different car but IIRC, my 1976 280C was in line and on the floor near the top of the floor mat and somewhat close to the brake pedal arm when depressed.

Michael

[WANT '71 280SEL]

250, He's talking about the transducer, not the amplifier. So, yes, the amplifier is by the brake pedal up over the underdash. The transducer should be on the back of the speedometer.

Thanks
David

[trainman715]

The cruise cotrol speed trasducer is not any where on or around the instrument cluster. I have searched all around with the cluster removed. This car does not have a speedometer cable. It is an electric speedometer. Maybe it is around the pickup for the speedometer, where ever that is. On the transmission maybe?

Originally Posted by trainman715

The cruise cotrol speed trasducer is not any where on or around the instrument cluster. I have searched all around with the cluster removed. This car does not have a speedometer cable. It is an electric speedometer. Maybe it is around the pickup for the speedometer, where ever that is. On the transmission maybe?

Some cars it is on the instrument cluster others on the transmission look in the DYI section under cruise control repair. Has anyone been able to fix the old style round VDO clocks from the 1960 and eraly 1970 ?
Dave S

[Mark DiSilvestro]

Tricky part of late '60s - early 70s Mercedes VDO clocks is getting the case apart. Unlike older VDO clocks, which had a removeable rear plastic cover, the 114-115 VDO clock movement (or at least the one I repaired from a '70 250C) is trapped inside a metal can, with the front chrome bezel crimped over the rim to seal it in place. One needs to carefully pry the chrome bezel from its grip on the can with a thin tool, trying not to badly crack or distort the chrome. Then, after the clock is repaired AND tested, the bezel can be worked back into place and re-crimped to the can, with a round tool such as a screwdriver handle or plastic mallet head. Hopefully, any slight re-crimping flaws won't be visible when the clock is reinstalled in the instrument cluster.

By the way, if you have an extra one of these VDO clocks that works, and no extra Mercedes to stick it in, you can set it on a bookshelf and power it off a 9 volt alkaline transistor radio battery.

Happy Motoring, Mark

Originally Posted by Mark DiSilvestro

Tricky part of late '60s - early 70s Mercedes VDO clocks is getting the case apart. Unlike older VDO clocks, which had a removeable rear plastic cover, the 114-115 VDO clock movement (or at least the one I repaired from a '70 250C) is trapped inside a metal can, with the front chrome bezel crimped over the rim to seal it in place. One needs to carefully pry the chrome bezel from its grip on the can with a thin tool, trying not to badly crack or distort the chrome. Then, after the clock is repaired AND tested, the bezel can be worked back into place and re-crimped to the can, with a round tool such as a screwdriver handle or plastic mallet head. Hopefully, any slight re-crimping flaws won't be visible when the clock is reinstalled in the instrument cluster.

By the way, if you have an extra one of these VDO clocks that works, and no extra Mercedes to stick it in, you can set it on a bookshelf and power it off a 9 volt alkaline transistor radio battery.

Happy Motoring, Mark

I thought I was the only one mine is powered off a tiny sealed lead acid battery it makes a great clock. I put the voltmeter out of a jaguar where the clock went on my 240D the clock is now on my shelf. I have a few of the old round VDO clocks with the porcelain housing instead of the metal can. I hope one day soon to tear one down and see if I can get it to work
Dave S