New Tach filter, new tach circuit board, now what?
04-06-2004, 05:22 PM
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New Tach filter, new tach circuit board, now what?
After all that work now the tach readings are totally useless. It is responsive, quicker to move than I expected it to be, (I expected the OEM '76 tach to be slow and lazy) but it reads wayyyyy to high.
Idle is about 4K RPM and of course, at freeway speed it is pegged. The circuit board is an Eckler's unit # 36963 and the tach filter was made by Fiero Specialties for the Vette (a referral from this forum)
Unplugging/bypassing the tach filter brings no joy either - it still reads wayy too high! Now what?
:cuss
Idle is about 4K RPM and of course, at freeway speed it is pegged. The circuit board is an Eckler's unit # 36963 and the tach filter was made by Fiero Specialties for the Vette (a referral from this forum)
Unplugging/bypassing the tach filter brings no joy either - it still reads wayy too high! Now what?
:cuss
04-06-2004, 05:54 PM
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Re: New Tach filter, new tach circuit board, now what? (SanDiegoPaul)
The tach filter will not affect RPM readings, just filters out the "noise" spikes.
Did your instructions for the tach board tell you to "rezero" the needle? Probably needs to be done if the idle is correct and the tach is reading 4000
Did your instructions for the tach board tell you to "rezero" the needle? Probably needs to be done if the idle is correct and the tach is reading 4000
04-06-2004, 06:01 PM
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Re: New Tach filter, new tach circuit board, now what? (KenSny)
Yea I was sure that's what the filter's function was ... but before, the tach was completely inop so I figured I would replace the filter first (easier!). Having no effect on the op of the tach, then I went in and did the circuit board.
No, unfortunately there were no instructions for zeroing the needle! :cuss
No, unfortunately there were no instructions for zeroing the needle! :cuss
04-06-2004, 06:50 PM
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Re: New Tach filter, new tach circuit board, now what? (SanDiegoPaul)
Paul, this link states that on 76 tach needle must be re-zeroed.
http://www.corvettefaq.com/c3/RebuildSpeedo.htm :seeya
http://www.corvettefaq.com/c3/RebuildSpeedo.htm :seeya
04-06-2004, 11:04 PM
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Re: New Tach filter, new tach circuit board, now what? (DMONSVETTE)
Paul, this link states that on 76 tach needle must be re-zeroed. http://www.corvettefaq.com/c3/RebuildSpeedo.htm
ahhhh, CRAPola! Whole thing's gotta come back out, sounds like. I may just unplug it and use a good one. I'm getting tired of messing with it!
ahhhh, CRAPola! Whole thing's gotta come back out, sounds like. I may just unplug it and use a good one. I'm getting tired of messing with it!
04-06-2004, 11:06 PM
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Re: New Tach filter, new tach circuit board, now what? (SanDiegoPaul)
If zeroing the tach does not help, try what I did. Sent my tacch and water temp gauge to Jason at Vette Instruments. I will be receiving it very soon, Jason replaced the board as well as the coil. Great service from him, can't say enough good about him. He has an e-mail, you will need to copy and paste: VetteInstruments@aol.com
