Author Topic: Tricks for reinstalling Tachometer  (Read 8918 times)

Coochas

  • Full Member
  • Regular
  • **
  • USA, MA, Sudbury
  • Posts: 54
Tricks for reinstalling Tachometer
« on: February 15, 2016, 23:40:36 »
Hi All,
I recently had my odometer and tachometer refurbished at Palo Alto.
I was able to reinstall the speedometer without too much drama but I just can't seem to be able to get my hand inside the dash far enough to reattach everything for the tach.

I'm using the method I found here (Joe A) in which I removed the steering wheel and dash (3 screw) panel to get at the instruments.    As with many things, I was able to disassemble the tach from the car but getting my hands back into that tight space is too hard for me.   On my last attempt I bent the mounting pin that goes into the back of the tach.  Ugh.  I think I can straighten it back out.

I am placing the bulbs/wiring into the tach before inserting it into the dash.   I have tried mounting the tach with the cab;e attached and not attached to make a little more room but to no avail.

Thanks!
1971 280SL Signal Red
Dave B.
Sudbury, MA USA

mbzse

  • Full Member
  • Platinum
  • ******
  • Sweden, Stockholm, Stockholm
  • Posts: 1748
Re: Tricks for reinstalling Tachometer
« Reply #1 on: February 16, 2016, 00:25:34 »
Quote from: Coochas
.../... I just can't seem to be able to get my hand inside the dash far enough to reattach everything for the tach
Did you loosen/remove the bracket that holds the blinker relay and the two large connectors? This will allow more room for your hand(s) from beneath.
/Hans in Sweden
.
« Last Edit: February 16, 2016, 01:24:13 by mbzse »
/Hans S

Coochas

  • Full Member
  • Regular
  • **
  • USA, MA, Sudbury
  • Posts: 54
Re: Tricks for reinstalling Tachometer
« Reply #2 on: February 16, 2016, 00:35:06 »
Yes, I have that harness out of the way!
1971 280SL Signal Red
Dave B.
Sudbury, MA USA

ja17

  • Full Member
  • Platinum
  • ******
  • USA, OH, Blacklick
  • Posts: 7414
Re: Tricks for reinstalling Tachometer
« Reply #3 on: February 16, 2016, 03:10:04 »
Sometimes I set the bracket in the dash before installing the tach. You can also squeeze the bracket legs slightly together so it grips the tack and stays in place while your trying to install the ground wire an thumbscrew. As last resort, remove the front seat, lay a nice thick pad down, so you can lay on your back and work comfortably. You can actually see what you are doing with some good light.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Tyler S

  • Associate Member
  • Platinum
  • ******
  • USA, CA, Encinitas
  • Posts: 1613
Re: Tricks for reinstalling Tachometer
« Reply #4 on: February 16, 2016, 03:47:57 »
My first go at installing the tach I ended up wraping my middle finger with double sided tape and sticking the thumbscrew to it. Then position the bracket and ground wire with your thumb and index fingers. Hold in place with your thumb and bring over the waiting thumbscrew. A varient of this may help.
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

mbzse

  • Full Member
  • Platinum
  • ******
  • Sweden, Stockholm, Stockholm
  • Posts: 1748
Re: Tricks for reinstalling Tachometer
« Reply #5 on: February 16, 2016, 08:51:56 »
Quote from: ja17
.../...while your trying to install the ground wire and thumbscrew.../...
Personally, I drill&tap an M4 hole in the instrument U-bracket, and I attach the ground wire with a toothed washer to it, as pre-assembly.
One less item to "aim" at the back, while installing tach and rev counter.
/Hans in Sweden
.
/Hans S

WRe

  • Full Member
  • Platinum
  • ******
  • Germany, Hessen, Seeheim-Jugenheim
  • Posts: 1454
Re: Tricks for reinstalling Tachometer
« Reply #6 on: February 16, 2016, 09:06:57 »
Hi,
to attache the ground to the bracket with an extra screw is a good idea as you can see it here: http://w113.eu/geschlossen/Reparaturen/tacho.htm but maybe also to pre-assemble the bracket. I haven't tried this version maybe next time.
...WRe
« Last Edit: February 16, 2016, 16:40:28 by WRe »

Coochas

  • Full Member
  • Regular
  • **
  • USA, MA, Sudbury
  • Posts: 54
Re: Tricks for reinstalling Tachometer
« Reply #7 on: February 16, 2016, 16:10:02 »
These are all great suggestions.   I'll try again and let you know!
1971 280SL Signal Red
Dave B.
Sudbury, MA USA

Coochas

  • Full Member
  • Regular
  • **
  • USA, MA, Sudbury
  • Posts: 54
Re: Tricks for reinstalling Tachometer
« Reply #8 on: February 18, 2016, 18:43:38 »
In my multiple attempts (and multiple hand cuts) I managed to bend the mounting pin on the tach.    I did manage to get it all together but despite my efforts to straighten the pin, it was too bent to allow full tightening of the bracket.

I called Hartmut at Palo Alto Speedometer who had just refurbished both the speedo and the tach and he very graciously offered to replace the pin for me free of charge.   Now that's service!   So my tach shipped out today and I'll have a go at it again in a few weeks.

BTW, is there anything wrong with securing the ground wire to one of the two screws that hold the mounting pin to the tach?   You just have to be careful when removing the instrument in the future.
1971 280SL Signal Red
Dave B.
Sudbury, MA USA

Tyler S

  • Associate Member
  • Platinum
  • ******
  • USA, CA, Encinitas
  • Posts: 1613
Re: Tricks for reinstalling Tachometer
« Reply #9 on: February 18, 2016, 18:54:14 »
You could also attach the ground wire to the threaded pin first with a very thin nut. The bracket and thumbscrew are far enough from bottoming out when tight.
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

Coochas

  • Full Member
  • Regular
  • **
  • USA, MA, Sudbury
  • Posts: 54
Re: Tricks for reinstalling Tachometer
« Reply #10 on: March 07, 2016, 03:22:29 »
I got my tach back from Palo Alto.   I did in fact attach the ground wire to the mounting pin using a small nut.
I think giving the project a rest for a week was a good thing as I was able to put the tach back in the dash and tighten everything up with no issues.
I took the car out for a short spin and everything is working perfectly.   Both odometers are working again.   The tach and speedo don't make any squealing noises and are very steady in their readings.

Thanks for all of the suggestions!
1971 280SL Signal Red
Dave B.
Sudbury, MA USA

Tyler S

  • Associate Member
  • Platinum
  • ******
  • USA, CA, Encinitas
  • Posts: 1613
Re: Tricks for reinstalling Tachometer
« Reply #11 on: March 07, 2016, 03:42:47 »
Thats Great! Glad that worked for you. It is nice to have a quiet steady speedo and tach while driving.
What did Palo Alto charge for both if I may ask?
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

Coochas

  • Full Member
  • Regular
  • **
  • USA, MA, Sudbury
  • Posts: 54
Re: Tricks for reinstalling Tachometer
« Reply #12 on: March 07, 2016, 14:27:57 »
Thats Great! Glad that worked for you. It is nice to have a quiet steady speedo and tach while driving.
What did Palo Alto charge for both if I may ask?

Sure.
The total was $781 including replacing the seals and chrome bezels and cross coast shipping.  The cost was about the same for each gauge.  He also cleaned them up so well they look new.
It's a specialized service that he offers for sure and the instruments work perfectly now.    His turnaround time was fairly quick.  I also give him props for replacing the pin that I bent solely for the cost of shipping.   
I replaced my tach cable which I obtained from Authentic Classics.
1971 280SL Signal Red
Dave B.
Sudbury, MA USA

RonB

  • Inactive
  • Senior
  • ***
  • USA, MN, Cottage Grove
  • Posts: 172
Re: Tricks for reinstalling Tachometer
« Reply #13 on: May 29, 2018, 18:46:26 »
Quick tip for attaching ground wire in back of tack.

I tape the wire to the bracket with a piece of electrical tape. Work

Works very well. 

Also I take the front seat out when under the dash for a time.

The seat is attached with cap screws - very easy to remove with a long swivel heat

Allen wrench on a 3/8 sock drive. Done in just moments.
Previously FULL Member twice with over 500 post

71 280SL - SOLD on BAT
97 E420      SOLD
85 300D      SOLD
85 R107 380SL
07 Volvo S60