Mech Tach Bouncing Around
Thread Starter
Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
Mech Tach Bouncing Around
OK I know this topic has been around, searched the archives and need a little more help. Testing the tach with a drill shows it still bouncing, so I assume its something with the magnet or...??
Is it worth trying to fix it myself? Like lube or just cleaning? I do not want to convert to electronic right now, just reinstall it and get the dash back together!!!
Is it worth trying to fix it myself? Like lube or just cleaning? I do not want to convert to electronic right now, just reinstall it and get the dash back together!!!
Race Director
Joined: May 2006
Posts: 18,756
Likes: 2,589
I would start with cleaning the cable and very light graphite lubrication away from the tachometer end of the cable. Is the exit angle from the distributor pretty smooth? You have checked the driven gear in the distributor coupling?
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,607
Likes: 7,053
From: New Or-leens Loo-z-anna
Get a square-end torque tip from and clamp it in the drill....insert the tip into the tap drive and slowly increase drill rpm to see if the needle bounce at different rpm.....if it doesn'tbounce connect the tach cable to the tach and use the drill to turn the other end of the tach cable....if the needle doesn-t bounce the distributor tach gears are probably dirty/dry/worn...check the gear play by putting a small tiop screwdriver in the distributor tach drive and rotating the screwdriver left 1/2 turn--then right 1/2 turn feeling for slack when changing rotation direction.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
The picture below is of a speedo, but the tach is made the same way only there isn't the second, third and other drive gears for the odometer.
I can fix it.. It usually runs around 110-135.00 plus shipping unless we find something else wrong with it. Turn around time is about 10-14 days If you are interested or want us to do this, email Mike on Monday at Mike@Willcoxcorvette.com and he will forward you the info needed to send it in.
Willcox
