Pagoda SL Group

W113 Pagoda SL Group => Electrical and Instruments => Topic started by: menesesjesse on October 19, 2009, 18:42:53

Title: Tach Cable replacement
Post by: menesesjesse on October 19, 2009, 18:42:53

My dad called me and mentioned that his tach on his 1966 230sl was making an awful noise before it stopped working all together.  Well looks like the cable snapped but the car is running fine.  What is the normal work time it takes to replace the cable with a new one?  Is it common for our cars that the cable does damage the tach itself?  Thanks
Jesse

Title: Re: Tach Cable replacement
Post by: J. Huber on October 19, 2009, 19:10:55

Hey Jesse. Not sure if you want the "book" rate time to do the job or just an idea of what's involved. I think it is a fairly easy thing to do but may take a little time.

The connection at the driver's side block (LHD) is obvious -- the other end is also simple to screw on/off by hand. However, to get to the back of the tach you need to remove the driver's side under-dash panel (if its there), then laying on your back in driver's well, fish a hand up to back of the tach. Some choose to remove the steering wheel and undo the wiring harness for more room. Not imperative. Then find the cable connection on the rear of the tach and screw off. To fish cable through firewall, you may have to remove the rubber grommet at the firewall. Inside an hour I'd say.

Title: Re: Tach Cable replacement
Post by: Jonny B on October 19, 2009, 23:14:53

You should check the tech manual. During the Blacklick event this year, Al Leiffring showed us that the tach cable can be pulled from the block connection, cleaned and re-installed, without disconnecting it from the back of the tach. With a broken cable, you will probably need to do the disconnect under the dash, but make sure that the cable is broken.

Title: Re: Tach Cable replacement
Post by: Ron on October 29, 2009, 04:39:16

Hi Jonny, and Al too!

OK, I pulled my tach cable out from the block end and it was in need of cleaning and lube.  The tach did work before I pulled the cable. I had to use pliers to get the cable to come out, and there was signs of rust about half way down the cable. It now slides easily in and out.

But the cable will not go back into the tach!  Did I pull something loose on the tach?  The cable will go the head and then won't "plug into" the tach fitting.  I can spin the cable and the needle jumps a bit, but it just won't go that last few mm.  It appears that the cable square end is not aligned with the female fitting up in the tach.  Any ideas on how to get it back in without having to dive into the foot well (again)?  ( I did the heater core a few months ago.) 

Ron

Title: Re: Tach Cable replacement
Post by: georgem on October 29, 2009, 05:43:42

Ron,

All you need is a bit of patience (and perhaps a beer) Push the cable back in gently until the cable hits the receiver in the tach then just keep gently pulling it back a touch, spinning it slightly and trying again. Eventually they will both line up and the cable will slide in - if you are lucky it could take a couple of beers.

Cheers

George
230SL
Brisbane.

Title: Re: Tach Cable replacement
Post by: Ron on October 29, 2009, 15:10:30

Thanks George, beers I can do.  There's several in the fridge, but due to work, I won't be able to try again until F afternoon.  Thanks for the suggestion.

Ron

PS I was just in Brisbane in Sept., first trip to Australia.  Great place.