Medhanical tachometer stopped working
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Medhanical tachometer stopped working
My tack stopped working, needle alway on "0". Could be the distributor drive, cable or tachometer itself. Can I spin the tack cable at the distributor end with a drill in order to somewhat isolate the problem? If so, should it turn CC or CCW? I had the dash out last winter for an interiour redo, maybe I didn't hook the cable back correctly? Any thoughts?
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
Grab the cable by the dist. Spin it with your fingers. Can't remember which way. Just spin it with a quick fast turn. You should be able to see the needle move some. Most likely is the dist. gear. sometimes the head goes bad but that is pretty rare.
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
There are 2 common failures:
1. Broken tach cable. To test, pull the cable off the distributor and spin it between your fingers. If the tach needle bounces and moves, the cable is okay and you have the second failure:
2. Sheared teeth on the distributor cross gear. This happens when the cross gear wears itself into the side of the distributor housing. It destroys the crossgear and the mainshaft. Additionally, the housing must be repaired in the thrust surface area before new parts can be successfully installed.
Intermediate
Joined: Apr 2005
Posts: 28
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From: Royal Oak MI
I just had the same problem after re-assembling my BB. I disconnected the tach cable and spun it, and the tach worked fine. Put it back together and nothing. It turns out that square end on the Distributor side of the cable had rounded off some (probably from not being tight enough). Because of this it did not engage the dist. enough. I replaced it with a $25 tach cable from Ecklers I beleive and no more problems.
