# Rally Tach



## Anthd7767 (Aug 8, 2020)

Hi,

Curious if anyone knows why a 65 rally tach would stay at just below 1000 rpm even if the engine rpm is varied? I checked continuity from the signal wire and all is good there it's on the correct coil terminal also... I did install a pertronix points replacement kit but I don't think that is the problem as it didn't work with the points either. Is there an easy way to test the tach on the bench I pulled the dash to clean it up and repair the redline needle as it fell off. If not anyone out there rebuild these?

Thanks in advance.


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## Mine'sa66 (Oct 30, 2019)

Anthd7767 said:


> Hi,
> 
> Curious if anyone knows why a 65 rally tach would stay at just below 1000 rpm even if the engine rpm is varied? I checked continuity from the signal wire and all is good there it's on the correct coil terminal also... I did install a pertronix points replacement kit but I don't think that is the problem as it didn't work with the points either. Is there an easy way to test the tach on the bench I pulled the dash to clean it up and repair the redline needle as it fell off. If not anyone out there rebuild these?
> 
> Thanks in advance.


Changing from the points to electronic ignition will generally screw up your tach. You will most likley need a tach adapter. Not a big deal. However, since it didn't work correctly beforehand, then you must have multiple problems. Not sure how to bench test one.


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## BLK69JUDGE (Jun 10, 2010)

bench test along side a known good aftermarket SUN tach at the same time

many original tachs have that same problem .... I even have an nos never installed hood tach
that doesnt read correctly

buy a quality repop and save your motor ,,,, put the original on the shelf


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## Colorado67GTO (Sep 11, 2014)

I am running Pertronix points replacement and my tach works fine.


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## Anthd7767 (Aug 8, 2020)

Thanks for all the responses.... I took the tach out of the cluster and tested it on the fender with a good Ground and it seemed to work fine...I went back under the dash and it seems the back light lamp that has the ground attached didn't have a ground connection. I'm going to add a ground strap to each of the cluster pods to insure a good ground moving forward...Thanks again all.
PS: just received my PHS email blitz with all the info regarding the car. Interesting and confirmed the car originally came with the 3.90 safe-T track rear behind the two speed auto & 4 barrel 389...pretty cool. I may be looking a ta 4 spd auto trans up grade sooner than later.....Thought the car was spooling up while driving but without a working tach tough to know


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