No tach signal from coil negative
#1
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Joined: Apr 2005
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From: Long Island
I have no tach signal to tach from negative coil terminal. Tach has ground, tach has power, wire from coil to tach is good. Faria Euro gauges replacing old teleflex. I tried the different post settings nada. Tach comes to 0 when key turned on. Just before I bought boat owner had done a breaker less distributor kit. I’m thinking I may have to grab tach from that?
Gauge I replaced was completely shot so I do not know if it worked then stopped working after distributor.
Gauge I replaced was completely shot so I do not know if it worked then stopped working after distributor.
#3
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Joined: Apr 2005
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From: Long Island
It’s an Accel Suporstock coil feeding a Mallory Breakerless distributor. Talked to Faria they said should get signal no problem. Can I ground test light hold it on coil - and see if pulses while running?
#5
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Joined: Jan 2006
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From: taxachusetts
if its running,its pulsing.tach should work if its connected to the - side of the coil.maybe run a wire from coil to tach.you running the required ballast resistor on the + side of the coil?
https://documents.holley.com/609_add.pdf
https://documents.holley.com/609_add.pdf
#8
Tach needs a +12v wire, good ground wire, and pulsing ignition signal. The "lighting" wire is not needed for the tach to work.
Make sure you show good 12 to 14 volts between the tach + and Gnd wires.
The signal should pulse (with test light) between + and coil -.
The "selector" switch on marine tachs can be a source of grief. There are usually 4/6/8 cylinder 4 stroke settings AND 12 pole outboard settings. With verified voltage between the + and GND to the tach. And a good signal wire, start jiggling and changing the selector switch to see if it is the culprit.
Make sure you show good 12 to 14 volts between the tach + and Gnd wires.
The signal should pulse (with test light) between + and coil -.
The "selector" switch on marine tachs can be a source of grief. There are usually 4/6/8 cylinder 4 stroke settings AND 12 pole outboard settings. With verified voltage between the + and GND to the tach. And a good signal wire, start jiggling and changing the selector switch to see if it is the culprit.
#9
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Joined: Apr 2005
Posts: 583
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From: Long Island
As usual was a bad ground, tach not getting full 12v. All set I appreciate it. When you first look it’s intimidating but as you peel the onion it’s actually stupid simple wiring gauges.



