Intermittent tach issues
Thread Starter
Burning Brakes
Joined: Aug 2015
Posts: 876
Likes: 694
From: Columbus, IN
Intermittent tach issues
Sometimes when I get in my '77 and turn the key on, the needle will move very slowly down to zero, and when I start the engine the needle goes up to ~2000 RPM and stays there. Sometimes it goes back to normal within a couple minutes, sometimes it takes a couple days. Is this a board issue? A wiring issue? Any input would be appreciated
Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
I'd say replace the tach board. Go to www.Willcox site to find moe info!
Last edited by mikem350; Apr 21, 2016 at 04:38 PM.
Thread Starter
Burning Brakes
Joined: Aug 2015
Posts: 876
Likes: 694
From: Columbus, IN
I bought a board a while back from a local corvette store but didn't install it because the tach started working again. If I remember correctly, the board failure symptoms described in the instructions that came with it were different than what mine is doing, so that's why I'm not sure what to look into first
Le Mans Master
Joined: Sep 2002
Posts: 5,236
Likes: 898
From: Myrtle Beach SC
Sometimes when I get in my '77 and turn the key on, the needle will move very slowly down to zero, and when I start the engine the needle goes up to ~2000 RPM and stays there. Sometimes it goes back to normal within a couple minutes, sometimes it takes a couple days. Is this a board issue? A wiring issue? Any input would be appreciated
As you in 77, the while dash must be nearly taken out to get to it...so no easy task. As suggested...check with Wilcox. Here's link to an article on tach issues...dated but still relevant
Tach Board Issues
Thread Starter
Burning Brakes
Joined: Aug 2015
Posts: 876
Likes: 694
From: Columbus, IN
The plastic clip broke off my signal wire, but i don't think it's an issue with the signal wire because when I disconnect it from the distributor the tach goes to zero (quickly when the tach is behaving, slowly when it's not). I guess I'll just replace the board and see what happens. I got a couple projects I need to do behind the dash anyway. Thanks guys
Thread Starter
Burning Brakes
Joined: Aug 2015
Posts: 876
Likes: 694
From: Columbus, IN
For people that might find this thread in the future:
I pulled out the tach and hooked it up to a 12v power supply, and had the same issue I described before, so it was definitely the board and not the wiring. I installed the new board and it's good as new.
I pulled out the tach and hooked it up to a 12v power supply, and had the same issue I described before, so it was definitely the board and not the wiring. I installed the new board and it's good as new.
Le Mans Master
Joined: Sep 2002
Posts: 5,236
Likes: 898
From: Myrtle Beach SC
Instructor
Joined: Oct 2002
Posts: 223
Likes: 20
From: jim thorpe pa
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Thread Starter
Burning Brakes
Joined: Aug 2015
Posts: 876
Likes: 694
From: Columbus, IN
I pulled the column out this time so it wasn't as difficult as the last time I pulled that side of the dash. I replaced most of the light sockets while I was in there because a couple of the wires broke off of the original sockets last time I had it apart. I get to take it apart again because I've got a few new issues to sort out now... Some of the contacts in the sockets don't touch the bulb, the high beam switch doesn't work when I pull back on the lever, and the ignition switch sticks in the start position. It seems like every time I pull the dash apart to fix one problem, another one comes up