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BJ8 tach

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Marvin Gruber

Marvin Gruber

Yoda
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Sorting out a couple of electrical gremlins. The tach is not working, checked for voltage, its there. Have the loop in the white wire. Needle will flicker when I remove grd wire but nothing while its running. Any thing else to check. If I need to send off for repair, who do you recommend?
thx,
Marv
 
Reverse the direction of the loop ... did you change the car from + to - ground ?
Nisonger instruments .
 
Healey Nut said:
Reverse the direction of the loop ... did you change the car from + to - ground ?
Nisonger instruments .
Click to expand...

Yep I will second those suggestions.
 
Marvin Gruber said:
Still pos grd, changed loop directions so guess I wil be sending it off.
Thx,
Marv
Click to expand...
Mine wasn't working until the temp got up by driving it and then reading was low. I converted to Neg ground and run Pertronix. Sent Tach to Nisonger and they installed new inards that will also work better with Pertronix and other hi-performance Ignition systems. About $300 and no more "loop" to contend with!
 
Hi Marv,

Prior to totally failing, did your tachometer read high? There is a known problem with our electronic tachometer where a 2uf capacitor deteriorates and eventually fails to a shorted or open circuit. It is reasonably easy to replace the part and recalibrate the tachometer.

Attached is a document written by Frank Filangeri that addresses this condition that could be the cause of your problem. One last point, Frank describes this capacitor as tubular in structure. However, I found my capacitor to be more disk like. so either could be presented.

Hope this helps,
Ray(64BJ8P1)
 

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  • BJ8 Tachometer Reads High.pdf
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Is the 2uf capacitor you are referring to the round disk-shaped component in the center of the image that has the paint burned off?

FullSizeRender.jpg
 
My tach didn't work at all. I sent it off to Nisonger and had it converted so no white wire loop. I got it back and it read 2x what is should read so I sent it back. I have it back now but have not installed yet.

Marv
 
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