Choose style:

Author Topic: Fixing factory tach  (Read 542 times)

0 Members and 1 Guest are viewing this topic.

Offline racerkilla

  • Eagle
  • **
  • Posts: 35
  • Thumbs Up 2
Fixing factory tach
« on: February 25, 2017, 01:51:04 PM »
So my factory tachs in both amx's did not work. I ended up buying a sun brand tach(the sweep is very close to the same) and used its new guts using the original amc face plate

I mocked up the new circuit board and two new screws into the old face plate to hold it. I took the original tach hand and cut just the white pointer off. Cut the new tachs orange pointer off and re glue the original on to the new tach base. The hole size was different.

new tach


old vs new pointer


new board on old face plate


old pointed glued to new base


When installing add 12v power so you can put the needle on the 0 rpm

Clean tach face done vs how yellowed the speedometer was. Used normal car wax and some elbow grease


both done


Online vangremlin

  • Administrator
  • AMC Eagles Den Addicted
  • ******
  • Posts: 3604
  • Thumbs Up 180
Re: Fixing factory tach
« Reply #1 on: February 25, 2017, 03:06:27 PM »
Very cool solution.  Thumbs up to you!
1981 Kammback 258 - "Pepe"
1980 Coupe 258 - "Ginger
1972 Gremlin X 304
1978 Gremlin 4 cyl 121 - sold
1964 TBird 390 - sold

Offline Prafeston

  • I <3 Wheels
  • Global Moderator
  • Eagle Turbo Diesel
  • *****
  • Posts: 1453
  • Thumbs Up 52
Re: Fixing factory tach
« Reply #2 on: February 25, 2017, 03:27:51 PM »
The Tach is still accurate? Cause I believe my tach is also non-function. Would love to fix that!
1983 AMC Eagle SX/4 - Penny

Offline racerkilla

  • Eagle
  • **
  • Posts: 35
  • Thumbs Up 2
Re: Fixing factory tach
« Reply #3 on: February 25, 2017, 03:33:33 PM »
It's pretty close because the sweep is off some from new to old faceplate. 1000 off over 8000 rpm sweep. So couple hundred at 5k. Works good enough for me

Offline Prafeston

  • I <3 Wheels
  • Global Moderator
  • Eagle Turbo Diesel
  • *****
  • Posts: 1453
  • Thumbs Up 52
Re: Fixing factory tach
« Reply #4 on: February 25, 2017, 03:48:05 PM »
While you had it apart could you see what was causing the old one to fail?
1983 AMC Eagle SX/4 - Penny

Offline racerkilla

  • Eagle
  • **
  • Posts: 35
  • Thumbs Up 2
Re: Fixing factory tach
« Reply #5 on: February 25, 2017, 09:34:39 PM »
Never looked into the burnt one.. Was happy to remove it because years back my black amx just died, no spark and left me. New pickup, coil, control box no start. Tach burnt up and was grounding coil so I had cut the wire going to it and it started. Now I run all hei anyways and carry spare module

Online amcfool1

  • Premium Member
  • Eagle Sport
  • *****
  • Posts: 485
  • Thumbs Up 21
Re: Fixing factory tach
« Reply #6 on: February 26, 2017, 01:37:07 PM »
hi, there is a thread here about using a Ford F150 300cid tach, it sweeps to 6k, got one in my 84, works great! thanks, gz

Offline racerkilla

  • Eagle
  • **
  • Posts: 35
  • Thumbs Up 2
Re: Fixing factory tach
« Reply #7 on: February 26, 2017, 07:41:59 PM »
Thats good to know..Problem is I need a tach for a v8 since that what is in all of my amx's. Maybe that style ford with v8. The sx4 I don't care how high its revving.. let it keep going

Online vangremlin

  • Administrator
  • AMC Eagles Den Addicted
  • ******
  • Posts: 3604
  • Thumbs Up 180
Re: Fixing factory tach
« Reply #8 on: February 26, 2017, 09:09:59 PM »
Thats good to know..Problem is I need a tach for a v8 since that what is in all of my amx's. Maybe that style ford with v8. The sx4 I don't care how high its revving.. let it keep going

The same Ford tach will work with a V8, there is an extra post on it the you run a ground wire to and you're good to go. Let me know if you need more info, I also have some of the Ford tachs for sale. 
1981 Kammback 258 - "Pepe"
1980 Coupe 258 - "Ginger
1972 Gremlin X 304
1978 Gremlin 4 cyl 121 - sold
1964 TBird 390 - sold

 

Page created in 0.048 seconds with 21 queries.