Tachometer doesn't work?
Thread Starter
Racer
Joined: Sep 2004
Posts: 497
Likes: 0
Tachometer doesn't work?
I was coming home from a drive and while parking it the garage I noticed the Tach wasn't moving...
I have the stock Distributor with the Petronix system in the Distributor with the Petronix Coil.
What do I check for?
Anyone?
Thanks
I have the stock Distributor with the Petronix system in the Distributor with the Petronix Coil.
What do I check for?
Anyone?
Thanks
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Tach cable, tach drive gear, distributor main shaft. If the cable is okay and connected correctly, you have possibly chewed the teeth off the drive gear. When those go, they usually take the teeth on the shaft with them.
Race Director
Joined: Sep 2005
Posts: 18,640
Likes: 121
From: Farragut,TN
From what i have read it's proably the main shaft of the dist. the gears that mesh get damaged and when they do both need to be replaced. you can check operation of the tach by disconnecting the cable at the dist. and spinning the cable by hand or with a drill to check the tack and cable.
Thread Starter
Racer
Joined: Sep 2004
Posts: 497
Likes: 0
That's Great.. That's Just Great!!!! LOL Mo Money!! LOL
694speed350 Thanks for your reply and I'll try that by hand...
*Now where would I get another Dist and Tach Cable?
Who sells them? Year one or something?
I just did my motor and put a Petronix Ignition in the original distributor to keep the stock appearance... Now I might have to fix the Tach/Distributor Arrghhh
Thanks
Mo Money!! LOL694speed350 Thanks for your reply and I'll try that by hand...
*Now where would I get another Dist and Tach Cable?
Who sells them? Year one or something?
I just did my motor and put a Petronix Ignition in the original distributor to keep the stock appearance... Now I might have to fix the Tach/Distributor Arrghhh
Thanks
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
you can get your tach converted to electronic operation (while still using your original dialface & pointer for a stealth upgrade).
Email me if you'd like more info:
tim-yvonne@juno.com
Email me if you'd like more info:
tim-yvonne@juno.com
Safety Car
Joined: Sep 1999
Posts: 4,930
Likes: 11
From: AnyTown NJ
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
It's usually the cable especially if yours takes the 90 deg bend off the dist.
http://forums.corvetteforum.com/show....php?t=1499948
http://forums.corvetteforum.com/show....php?t=1499948
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Heel & Toe
Joined: Apr 2004
Posts: 24
Likes: 0
From: Indianapolis IN
can't solve mech. tach problem
Augustus,
Just curious if you solved your problem. I have the same problem with my mechanical tach on my '69. I can attach a drill to the distributor end and make the gauge function, but when it's all hooked up it doesn't work. I bought a new cable and took the gear out of the distributor (looks good) adjusted the end play of that gear and still no needle movement. I can hook the cable to the distributor and it turns too. Any ideas guys?
Just curious if you solved your problem. I have the same problem with my mechanical tach on my '69. I can attach a drill to the distributor end and make the gauge function, but when it's all hooked up it doesn't work. I bought a new cable and took the gear out of the distributor (looks good) adjusted the end play of that gear and still no needle movement. I can hook the cable to the distributor and it turns too. Any ideas guys?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Try putting the dist gear on the cable and then turning it. It's possible the cable side of the gear is no longer square. Sounds like you've checked the cable, looked at the gear, ran the tach with a drill, so look at what's left.
Heel & Toe
Joined: Apr 2004
Posts: 24
Likes: 0
From: Indianapolis IN
I repositioned distributor and now tach is working!
I read about positioning the distributor so that the vacuum can points to the passenger side of the car. I did that and now the tach works. I am guessing that there was too much of a bind in the cable and/or that there is just enough give in the gears inside the distributor housing that they weren't meshing. Or maybe there is some slippage somewhere to prevent the cable from breaking. Anyway, it also makes getting the cable on and off the distributor much,much easier. Mine was mashing into the firewall. I can't wait to drive it and see how much rpms I have at different speeds. I put this car together from a basket cast, and this summer is the first time it's moved under it's own power in 20 years. 
I am guessing that there was too much of a bind in the cable and/or that there is just enough give in the gears inside the distributor housing that they weren't meshing. Or maybe there is some slippage somewhere to prevent the cable from breaking. Anyway, it also makes getting the cable on and off the distributor much,much easier. Mine was mashing into the firewall. I can't wait to drive it and see how much rpms I have at different speeds. I put this car together from a basket cast, and this summer is the first time it's moved under it's own power in 20 years.
Last edited by carnutbob; Dec 26, 2006 at 08:10 PM. Reason: spelling
Tech Contributor
Joined: Aug 1999
Posts: 14,373
Likes: 6,371
From: At my Bar drinking and wrenching in Lafayette Colorado
Augustus -
You might want to check out this thread:
http://forums.corvetteforum.com/show...highlight=lars
I talk a bit about how the crossgear locks up and how you need to have it fixed.
You might want to check out this thread:
http://forums.corvetteforum.com/show...highlight=lars
I talk a bit about how the crossgear locks up and how you need to have it fixed.
