Tach Grounding Out on CVX18

[dszczucinski]

Morning all!

Can anyone snap a picture of the back of their tach gauge on a later 80s CVX? My tach gauge was grounding out causing a no spark condition and I have a feeling the previous owner connected the gray tach wire in the wrong spot or the gauge is toast. Any help would be appreciated as my gauge only has symbols no words on the back.

[Plugcheck]

As a troubleshooting steps, I'd disconnect the grey(generally)wire at the tach and test.  Could be a short in the wiring.  Or possibly someone tied the oil pressure sensor at the coil as a failsafe to lose of oil pressure.  We always did that in eace cars.   Anyway, here are four pictures of various dashes I have, 1st in 92 Baja 260, second is 85 Timi, 3rd is 79 CVZ-18, and fourth is larson.   Hope this helps.

[Plugcheck]

3and4, file size too big.

[Hyperacme]

You can get owners manual here in PDF …
https://www.glastron.com/uploads/2017/3/80-IO-GL-MANUAL.pdf

[Glastronjohn18]

 Here's the dash on my '86 CVX 18, it should be the same as yours.
 Hope this helps you.









Here is the back of the tach on my 1986 CVX 18.






Wire ID

Blue -  dash light, goes to speedo light

Large Black -  Ground from wire harness, goes to center terminal, common to other black wires

Gray-   goes to ignition coil

Black 3- goes to black wires on temp guage

Purple- from wire harness, usually +12v when ign is on

Black 2- goes to black wires on speedo,

[dszczucinski]

Thanks all! I did locate the S terminal (my gauges are completely different though lol). Unfortunately the tach appears to be dead, probably why the previous owner moved the wire to the wrong spot.