Noisy Tachometer

[alchemist]

My tachometer on my 1967 230SL was working fine until we got the subzero temperatures in the State of NY. Although the SL is always in the garage with an average temperature of 30 F when it is subzero outside the garage. Under these conditions, the tachometer started making a strong humming noise. To save it, I disconnected the cable from the tachometer. It is evident that the lubricant in the cable and the tachometer are becoming more viscous under these temperatures. My question: Is the cable needs to be lubricated or it should be replaced? If so, what type of lubricant? Is the tachometer it itself can be lubricated or serviced?

[rmmchl]

It needs replaced. They make that noise when they go bad. I wouldn't  bother with trying to lube it. It unscrews from the back of the tach. Kinda hard to get your hand back there , while you are trying to lie on the floor under the steering wheel, but most of us have done this. It is an easy fix , and the new cable is under $100.00.

[pj]

I had the same thing happen when I drove the car on a dry, cold day here in SW Ontario. But the humming noise stopped once things warmed up a bit inside the mechanismus.

I'm not even going to try to replace it until I either train a 6-yr-old to reach in back there, or take the whole thing apart for a general overhaul.

[rmmchl]

they are not supposed to make noise in any weather conditions. German engineers would not put up with that. I stick to my theory that it needs replaced.

[mmizesko]

Guys,

even with oiling my cable, and replacing it with a new one, anytime the temp dropped under 45 degrees F, my tach howled.  If I touched the glass on the tach, I could feel the vibration.  I ended up sending it off to be taken apart and lubricated /cleaned on the inside.

FYI.  If you feel the vibration on the front of the instrument, it's probably an "inside" issue.

Mike Mizesko
Columbus, OH