72 intermittent tach
Thread Starter
1st Gear
Joined: Jun 2014
Posts: 1
Likes: 0
From: BRICK NJ
72 intermittent tach
My tach becomes erratic on hot days when idling in traffic and engine temperature starts to climb. Needle either bounces or drops to zero. As soon as engine temperature drops or running car on cool days ( 80 degrees or less) tach works fine. Any thoughts on what the problem may be?
Oringinal Owner, 72 LT1
Oringinal Owner, 72 LT1
Team Owner
Joined: Sep 2006
Posts: 31,270
Likes: 4,362
From: Westminster Maryland
Hi Erich,
WELCOME! FIRST POST! And an LT-! too!!!!
I replied to your thread on the DB too.
While it's certainly possible that the cable is the cause of your problem, I really think it's more likely the heat is affecting the tach mechanism.
The tachometers can be very successfully repaired… but there's $$ involved, plus getting it out and back in isn't a pleasant job.
Hoping you find a cable or cross gear problem!
We MUST have some pictures of your car…. please!
Regards,
Alan
WELCOME! FIRST POST! And an LT-! too!!!!
I replied to your thread on the DB too.
While it's certainly possible that the cable is the cause of your problem, I really think it's more likely the heat is affecting the tach mechanism.
The tachometers can be very successfully repaired… but there's $$ involved, plus getting it out and back in isn't a pleasant job.
Hoping you find a cable or cross gear problem!
We MUST have some pictures of your car…. please!
Regards,
Alan
Last edited by Alan 71; Jun 9, 2014 at 04:37 PM.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I have had many a tach out and dist out and cables replaced. If the dist or cable are bad it usually is all the time. Broken pieces. The tach head could be the culprit but if there are lots of miles on the car it could be all 3 of them.
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Start with the easy and disconnect the cable from the dist when everything is hot and the dist isn't working. Connect a battery drill to the cable and run in reverse (I think) to see if the tach will work, if yes its time to pull the dist and look at the cross gear drive, if no its most likely in the tach itself. FWIW if the tach has not been serviced before I would pull it, strip it and put in new lubricant before it does fail as the grease in the dist if it has not been serviced will be useless by now.
