Speedometer part # - Page 2 - PeachParts Mercedes-Benz Forum

rrgrassi · #16 08-10-2007, 05:00 PM

Quote:

Originally Posted by 300TDBioBenz

I'm looking for an 85 cluster if you know where one is.

PM your e-mail address to me and I'll foward the quotes I recieved.

rrgrassi · #17 08-10-2007, 05:01 PM

Quote:

Originally Posted by cavaliers16

Sounds good. My odometer is off by a lot too, so I would have to guess that it is from the '85, but I'll see if John can get the number off his 85 first.

Sounds good to me!

cavaliers16 · #18 08-11-2007, 12:37 PM

Bump again.

Anyone with an '85 want to post the part # from the speedometer?

cavaliers16 · #19 08-11-2007, 10:35 PM

This was not as easy as I had expected. I think I need some more input before I swap these out. Here is what I have so far- please contribute if you can:

Year, Model, Owner, Part #, SP, SP, SP, Reads...

82, D, Craig, 123 542 27 57, 29, 46, 77, ?, not original

82, D, toomany MBZ, 123 542 28 57, 28, 43, 72, ?, not original

83, D, cavaliers16, 123 542 18 57, 26, 47, 76, Fast

84, CD, toomany MBZ, 123 542 28 57, 28, 43, 72, ?

85, D, Jeremy5848, 123 542 27 57, ?, ?, ?, Correctly

So, both Craig and Jeremy have the same speedo. toomany MBZ has speedos with similar part #s but different shift points. Mine is screwy across the board.

#20 08-11-2007, 10:48 PM

Wow, that's interesting. Just a note that mine was not original for the 82D, it appeared to be from a 83/84 but it did seem to match the original for speed. At this point, I would probably just call the dealer and ask for the correct part number for an 85.

cavaliers16 · #21 08-11-2007, 10:52 PM

Quote:

Originally Posted by Craig

Wow, that's interesting. Just a note that mine was not original for the 82D, it appeared to be from a 83/84 but it did seem to match the original for speed. At this point, I would probably just call the dealer and ask for the correct part number for an 85.

Forgot about that- I'll make a note with yours and with toomany MBZ's 82 as well. I'll give the dealership a call on Monday.

cavaliers16 · #22 08-14-2007, 11:16 AM

I called the dealership this morning and the parts guy said that those are not the part numbers.

Of course...

The 83 and 84 speedometers have the following part numbers (I'll get the 85 this afternoon when I call back):
009 542 9406- original speedometer
010 542 7506- replacement speedometer (new part)

I have yet to locate the number on the speedo, but when I finally pull the cluster again I'll post it.

BIGRED · #23 11-22-2007, 01:44 AM

Quote:

Originally Posted by cavaliers16

This was not as easy as I had expected. I think I need some more input before I swap these out. Here is what I have so far- please contribute if you can:

Year, Model, Owner, Part #, SP, SP, SP, Reads...

82, D, Craig, 123 542 27 57, 29, 46, 77, ?, not original

82, D, toomany MBZ, 123 542 28 57, 28, 43, 72, ?, not original

83, D, cavaliers16, 123 542 18 57, 26, 47, 76, Fast

84, CD, toomany MBZ, 123 542 28 57, 28, 43, 72, ?

85, D, Jeremy5848, 123 542 27 57, ?, ?, ?, Correctly

So, both Craig and Jeremy have the same speedo. toomany MBZ has speedos with similar part #s but different shift points. Mine is screwy across the board.

Did you conclude the above correct?

I have a 123 542 27 57 and am trying to figure out what year and therefore the rear end that matches it.

For the life of me I can't understand how that number is not the part number. I guess an option is to call VDO and see if they can help.

Thanks
Don

cavaliers16 · #24 11-24-2007, 10:28 AM

I never did figure it out- the EPC doesn't have the faceplate as an option. If you can figure out what it needs, please post it!!! The dealership doesn't know what it means. They don't even know where the speedometer part number is located on the assembly. Clearly mine is wrong, but I can't figure out which one to replace it with.

So, anyone else want to contribute to the faceplate part number list?

BIGRED · #25 11-24-2007, 12:21 PM

I ran a speedo check following someone whom passed through 3 different speed limits. I would have to say that the Speedo that I installed is correct speedo (123 542 27 57) for operation with the 2.88 gears. I will verify this test sometime over the weekend.

dieseldiehard · #26 11-24-2007, 02:58 PM

Quote:

Originally Posted by cavaliers16

I never did figure it out- the EPC doesn't have the faceplate as an option. If you can figure out what it needs, please post it!!! The dealership doesn't know what it means. They don't even know where the speedometer part number is located on the assembly. Clearly mine is wrong, but I can't figure out which one to replace it with.

So, anyone else want to contribute to the faceplate part number list?

FWIW My '85 300TD shows this on the faceplate: 123-542-2757

The dealer is the last place to go for speedometer problems, they will just order a new one or send a defective one to a speedo shop.
What happens with speedometers as they age is the magnets lose their strength and they lose calibration. A good shop can readjust the reading using a known rotating shaft.

Now, no one has mentioned it in this thread but the important thing related to a speedometer is the K-factor.
The K-factor is what the VDO factory uses to supply calibrated units to Mercedes. Look for a small paper tag somewhere on the back of the speedometer with the K-#### on it. It is easily lost as the adhesive is cooked after a couple decades, but there is also a small tag inside the unit also, it is imperative you know the K factor if you are going to have a shop calibrate the unit. This factor enables an experienced speedometer tech to adjust the magnets to set the speed using specified rpm and the pointer should be right on 60 MPH. If not, they adjust it internally, how I don't know. If I knew I would have saved a ton off money from the speedometers I have taken to Palo Alto Speedo.
To use the K-factor technique you must be certain the speedometer on your car is the original and you haven't changed the differential otherwise you need to run the car over a measured distance and count the number of revolutions the drive cable makes. see:

http://www.paspeedo.com/

dieseldiehard · #27 11-24-2007, 03:07 PM

Quote:

Originally Posted by cavaliers16

This was not as easy as I had expected. I think I need some more input before I swap these out. Here is what I have so far- please contribute if you can:

Year, Model, Owner, Part #, SP, SP, SP, Reads...

82, D, Craig, 123 542 27 57, 29, 46, 77, ?, not original

82, D, toomany MBZ, 123 542 28 57, 28, 43, 72, ?, not original

83, D, cavaliers16, 123 542 18 57, 26, 47, 76, Fast

84, CD, toomany MBZ, 123 542 28 57, 28, 43, 72, ?

85, D, Jeremy5848, 123 542 27 57, ?, ?, ?, Correctly

So, both Craig and Jeremy have the same speedo. toomany MBZ has speedos with similar part #s but different shift points. Mine is screwy across the board.

You are wasting time publishing the part numbers off speedometers, the important thing is the K-factor, as described previously.
If I had copied down the K-factors over the years I have worked on Instruments I would have the answers to your problems. But I didn't record anything

Swap a known speedometer from a similar model, and you still going to have error if the speedo has lost calibration over time. These things all drift over the years because the magnets age. Maybe that is why speedometer shops are in business?

cavaliers16 · #28 11-24-2007, 06:21 PM

Didn't realize that about the K factor. Well, I guess I will find a speedometer shop around here. Thanks!

BIGRED · #29 11-24-2007, 09:16 PM

Assuming that the original or an exact replacement part was installed in the car and the speedo is off, that is one set of issues.

The reason for discussion of part numbers and the cars, is to create a reliable source of information so that one can confirm the right speedometer is installed. Given the age of the cars and all the parts swapping...its reasonable. If that means we should add or do it from the paper tag...I am all for it.