tach not working
Thread Starter
Burning Brakes
Joined: Dec 2005
Posts: 1,179
Likes: 100
From: cranford nj
tach not working
Need a little help i have a 71 all stock with a mechanical tach.I have replaced the cable gear washer and thrust button, Tach worked for a couples of days then all of the sudden it stopped working.Checked the cable to the tach still conected, looked under the hood and found it loose at the distributor to hot to check looked like the brass couple was loose can they back out or is something wrong.
Pro
Joined: Mar 2003
Posts: 553
Likes: 1
From: Valparaiso IN
This is what I did.. Pulll the cable off of the distributor. Put my drill on the cable end. Spin the drill in reverse. This will move the cable, and tach drive in the dash. If you see the needle move on the tach, then you are good to the dizzy. Those brass gears on the diz do get stripped..
Good luck
Good luck
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Originally Posted by blue by you
looked like the brass couple was loose can they back out or is something wrong.
I had the same problem at one time.
This may sound primitave but it works fine.
Note: There are slots in the brass coupling for either a VERY wide thin blade screwdriver or a flat blade spanner wrench..or something similar ..I do have a spanner that fits the slot but I could not get access to the slot while the distributor is installed... so heres the way I tightened it.
I removed the cable from the dist end then with a heavy rag wrapped around the brass fitting I turned it in by hand as tight as I could then with the rag still protecting the threads I used a pair of pliers to snug the brass without destroying the threads.
Hook the tach cable back up
You dont have to tighten it very much, just snug by hand.
Pro
Joined: Mar 2003
Posts: 553
Likes: 1
From: Valparaiso IN
Originally Posted by OldSchool
This is what I did.. Pulll the cable off of the distributor. Put my drill on the cable end. Spin the drill in reverse. This will move the cable, and tach drive in the dash. If you see the needle move on the tach, then you are good to the dizzy. Those brass gears on the diz do get stripped..
Good luck
Good luck
Melting Slicks
Joined: Mar 2005
Posts: 2,094
Likes: 298
From: Midlothian VA
Originally Posted by blue by you
Need a little help i have a 71 all stock with a mechanical tach.I have replaced the cable gear washer and thrust button, Tach worked for a couples of days then all of the sudden it stopped working.Checked the cable to the tach still conected, looked under the hood and found it loose at the distributor to hot to check looked like the brass couple was loose can they back out or is something wrong.
If you replaced the gear and it worked for a while and then stopped you may have striped your new gear by running it against the worn out mainshaft gear. You should usually replace both the cross shaft gear and the mainshaft as a set.
Safety Car
Joined: Jun 2004
Posts: 4,652
Likes: 80
From: Lakeland Florida
If the main shaft drive gears are bad, then they will quickly chew up the new tach drive gear. You may need to pull the distributor out, and dissasemble to look at the main drive shaft gear.
kdf
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Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
blue by you...
One quick thing to check before pulling the distributor...
It is possible for the cable to separate from the metal coupling on the end of the cable that attaches to the distributor. The coupling is simply crimped onto the end of the cable. If the cable slips out just a little it can lose contact with the distributor even if the coupling is tight on the distributor. Just give the cable a tug. If it is loose, it will be readily apparent. And yes, you can sometimes get away with just pushing it back into the coupling...
Good luck... GUSTO
One quick thing to check before pulling the distributor...
It is possible for the cable to separate from the metal coupling on the end of the cable that attaches to the distributor. The coupling is simply crimped onto the end of the cable. If the cable slips out just a little it can lose contact with the distributor even if the coupling is tight on the distributor. Just give the cable a tug. If it is loose, it will be readily apparent. And yes, you can sometimes get away with just pushing it back into the coupling...
Good luck... GUSTO
Thread Starter
Burning Brakes
Joined: Dec 2005
Posts: 1,179
Likes: 100
From: cranford nj
Thanks for all of the input.When i bought the car the tach did not work bought all the new parts installed them and it work for a weekend according to all the paper work I have on the car the tach hasen't worked since 72 I'll look into all mentioned and get back to all.
Thanks again for all your knowledge.
Thanks again for all your knowledge.