rst08tierney

I was given an extra cluster today for my 67.

I wanted to test it out so I removed my old cluster and replaced it with the new one.


Here is my question.

If a single gauge is broken and not working properly, it will not send power to the sender or will it send power with no gauge reading?


ie : broken oil pressure gauge cant send signal to oil pressure sender correct?

Thanks

snorulz

the oil pressure sender "sends" the signal to the gauge, hence the name sender

chris66dad

The oil gauge gets its voltage from the instrument voltage regulator (approx. 5 volts) and it goes "through" the gauge and out to the sender. The oil pressure sender changes resistance with pressure and this causes the gauge to see a voltage change. The scale is calibrated to this voltage drop.
Ground the white/red wire on the back of the gauge, the gauge will go full scale to verify it works. Do not leave it grounded for too long because it can damage the movement due to heat from the current flow.

Wiring Schematic:
http://4.bp.blogspot.com/_xzht_ppgu8...0-h/Gauges.JPG

rst08tierney

that picture is just what I need but its too small to read. can you blow that up and re post for me?

chris66dad

http://4.bp.blogspot.com/_xzht_ppgu8...0-h/Gauges.JPG

The website only likes small images. Here is a web link for you!
Good Luck!

rst08tierney

Great! This helped an EXTREME amount!

Looks like everything works except the temp gauge. Question though. When I tested the gauge feed wires with the meter my results were the following so I believe my results are accurate. Please correct me if im wrong.

Oil Gauge Wire - Flashing red light

Coil Wire - Constant Red light

Temp Wire - No reading (Temp gauge broken)

I also heard if your oil gauge SENDER UNIT is broken the gauge will act like you are grounding it. Is this right as well?

chris66dad

Oil Gauge Wire - Flashing red light The Instrument Voltage Regulator "pulses" a 5 volt average signal- Good
Coil Wire - Constant Red light Seeing 12V- Good
Temp Wire - No reading (Temp gauge broken) did you try grounding the terminal that goes out to the sender? This should make the scale go full scale. Another test would be to lift BOTH wires off the gauge and measure RESISTANCE between the 2 terminals. You will see an open circuit (no resistance) if the gauge is bad.

I also heard if your oil gauge SENDER UNIT is broken the gauge will act like you are grounding it. Is this right as well? The sender can short internally causing the gauge to go full scale or it can open causing no signal because the voltage will not get to ground to complete the circuit

Can you mix and match between the 2 gauge clusters to get all the gauges working? That would make you golden!