C3 General General C3 Corvette Discussion not covered in Tech
Sponsored by:
Sponsored by:

speedometer problems

Thread Tools
 
Search this Thread
 
Old Jul 12, 2021 | 03:32 PM
  #1  
Geoff Leach's Avatar
Geoff Leach
Thread Starter
Heel & Toe
 
Joined: Dec 2020
Posts: 18
Likes: 0
From: barnsley england
Default speedometer problems

I have a 1978 pace car and very low milage , was working fine and the odometer was working then after about 300 mile the speedo needle start ticking and flicking as it ticked, on the way home I realised the odometer stopped recording , When I arrive I unscrewed the speedo cabe to the cruise and spun the cable with my fingers and was free then tightened up then free again , That accounts for the ticking I believe that theres a plastic gear thats had a wobbler , Has anyone had the speedo out and were you able to access the problem , Another friend up Scotland with a pace car and his has just stopped recording as well bit no flicking of the needle , it was just like you had a broken cable ,
any help appreciated, Geoff

Last edited by Geoff Leach; Jul 12, 2021 at 03:33 PM.
Reply
Old Jul 12, 2021 | 04:50 PM
  #2  
ledger35's Avatar
ledger35
Burning Brakes
Veteran: Army
 
Joined: Mar 2021
Posts: 1,212
Likes: 62
From: Gainesville, Florida
Default

Mine was ticking and not working, replaced the cable into the transmission and not only did the ticking go away but the speedometer worked again! Good Luck
Reply
Old Jul 12, 2021 | 04:57 PM
  #3  
doorgunner's Avatar
doorgunner
2026 Loser of the Year
Supporting Member
10 Year Member
Veteran: Army
Photogenic
Photoriffic
 
Joined: Sep 2013
Posts: 36,573
Likes: 7,015
From: New Or-leens Loo-z-anna
Default

My '68 does not have cruise so I can't advise you about that part. I have some pics in my thread about the odometer problem I experienced.....it may or may not be the cause of your problem.
You can unscrew the speedometer cable at the transmission to see if the plastic gear inside has worn teeth or the female end of the gear shaft is rounded rather than square-shaped.
The link below will take you to the speedometer repair in my thread.
NOTE: Removing the speedometer from the dash should be a LAST RESORT after all other repairs fail to solve the odometer problem.

https://www.corvetteforum.com/forums...post1590139457
Reply
Old Jul 12, 2021 | 06:03 PM
  #4  
Geoff Leach's Avatar
Geoff Leach
Thread Starter
Heel & Toe
 
Joined: Dec 2020
Posts: 18
Likes: 0
From: barnsley england
Default

The cable from the Speedo to the cruise unit is only short so when I turn the inner cable it turns a few turns ok the gets stiffer so the problem must be inside the speedo as it’s not moving the miles meter but the speedo needle is moving with the little jerk when it gets tight .you’ve got your work cut out there bud , we’ll done to you .Geoff
Reply
Old Jul 15, 2021 | 11:22 PM
  #5  
doorgunner's Avatar
doorgunner
2026 Loser of the Year
Supporting Member
10 Year Member
Veteran: Army
Photogenic
Photoriffic
 
Joined: Sep 2013
Posts: 36,573
Likes: 7,015
From: New Or-leens Loo-z-anna
Default

Originally Posted by Geoff Leach
The cable from the Speedo to the cruise unit is only short so when I turn the inner cable it turns a few turns ok the gets stiffer so the problem must be inside the speedo as it’s not moving the miles meter but the speedo needle is moving with the little jerk when it gets tight .you’ve got your work cut out there bud , we’ll done to you .Geoff
The pics below show the damage that caused bouncing needle/inop needle........inop odometer also.

Removing shaft @1 with damaged teeth


Damaged teeth om mating shaft.......


Reply
Old Jul 16, 2021 | 01:33 AM
  #6  
Eliredandblack's Avatar
Eliredandblack
Melting Slicks
Liked
Loved
Community Favorite
Top Answer: 1
 
Joined: Feb 2018
Posts: 2,321
Likes: 720
From: Marietta GA
Default

I had the manual tranny rebuilt, along with a new clutch / flywheel, plus a new plastic gear for the speedo. Attempting to get the speedo to work. After all that the speedo worked for about 150 miles, still bouncing before it finally quit. So I removed the tach / speedo then sent them off to be rebuilt. Putting them back into the car was a nightmare, because trying to move the 48 year old wiring harness around and putting the drivers dash back in, was the worst project that I ever done. If you go to the trouble of removing the speedo / tach, make sure you take them to a competent professional that knows how to repair them. Good Luck.
Reply
Old Jul 16, 2021 | 09:09 AM
  #7  
7T1vette's Avatar
7T1vette
Team Owner
15 Year Member
Community Builder
Community Influencer
Top Answer: 5
 
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
Default

Change the speedo cable FIRST, before digging deeper... If you put 'lube' on the cable, make sure that you use ONLY dry graphite powder lube. Any kind of oil/grease will gum-up the cable/sheath assembly and could work its way up into the speedo mechanism. If you find oil/grease on the present cable when you remove it, I highly recommend that you use a spray cleaner or mild solvent to shoot thru the sheath (both ends removed from speedo/trans) from the speedo end, to clear that stuff out of the sheath before you install the new cable.
Reply
Old Aug 12, 2021 | 05:09 PM
  #8  
Geoff Leach's Avatar
Geoff Leach
Thread Starter
Heel & Toe
 
Joined: Dec 2020
Posts: 18
Likes: 0
From: barnsley england
Default

We I left it a couple of week after oiling it slightly and check the inner cable and it was smooth when turned ? So connected it up and guess what it works fine!!!! Speedo smooth and odometer working perfect, tooth fairy must have been !
Reply

Get notified of new replies

To speedometer problems

Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-1

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-2

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-3

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-4

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-5

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-6

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-7

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-8

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-9

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski




All times are GMT -4. The time now is 03:53 PM.

story-0
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-1
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-2
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-3
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-4
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-5
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-6
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-7
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-8
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-9
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE