69 corvette tach problems
Thread Starter
Pro
Joined: May 2013
Posts: 570
Likes: 22
69 corvette tach problems
I have been trying to diagnose a bouncy tachometer in my 69 427 coupe.
I removed the dash in order to install a vintage air kit. I replaced the tach cable while the dash was removed. I also replaced the tach needle.
i installed the needle according to the Wilcox video instructions. When I twist the dial in the back by hand it appears to function normally. When I reinstalled the dash and started the engine the tach needle bounces wildly and will eventually fall off
can someone help me diagnose this? I can’t tell you how many times I have removed and reinstalled the dash. Beyond frustrated.
I removed the dash in order to install a vintage air kit. I replaced the tach cable while the dash was removed. I also replaced the tach needle.
i installed the needle according to the Wilcox video instructions. When I twist the dial in the back by hand it appears to function normally. When I reinstalled the dash and started the engine the tach needle bounces wildly and will eventually fall off
can someone help me diagnose this? I can’t tell you how many times I have removed and reinstalled the dash. Beyond frustrated.
Thread Starter
Pro
Joined: May 2013
Posts: 570
Likes: 22
Racer
Joined: Sep 2019
Posts: 349
Likes: 44
From: Spokane, WA
I had a similar problem along with chirping from both speedo and tach cables. I disconnected the tach cable at the distributor and sprayed PJ1 Cable lube down the open end, holding the cable up so it would work its way down the cable. Did the same for the speedo but disconnected at the trans. Problem solved for both.Dead quiet and both steady.
Melting Slicks
Joined: Jan 2000
Posts: 3,326
Likes: 523
From: home
did you try to spin the tach cable with a drill and see if the needle bounces? I'd reclock the distributor so the vacuum advance comes out behind the distributor box bracket to lessen the amount of bend in the tach cable.
Thread Starter
Pro
Joined: May 2013
Posts: 570
Likes: 22
I will try that when I remove it. I have a 90 degree joint at the distributor to address the cable turn there. The turn at the fire wall is a little sharp is where I think it is binding.
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