1966 all gauges pegging

[Sun lover]

I recently developed a problem, My oil fuel and temp gauge all going full to the right. Any ideas as to what the cause could be and how to check?

 

[cougarsunlimited]

The IVR (instrument voltage regulator) contacts have stuck together and is sending 12V instead of 5V to the gauges.
This regulator is located on the back of the instrument cluster.
The part number is B9MZ-10804-C.

 

[Sun lover]

Thanks for the info, I did replace the voltage regulator ( not a fun job!) and now the gauges read but they all read low. For instance, when the tank is full, the gauge reads approximately 1/2 and the temp barely gets off of cold. I know that the ground is good and when I checked it with a meter it appears to be pulsing in the 5 volt range. all of the gauges were working with the old regulator. Any ideas?

 

[cougarsunlimited]

Thanks for the info, I did replace the voltage regulator ( not a fun job!) and now the gauges read but they all read low. For instance, when the tank is full, the gauge reads approximately 1/2 and the temp barely gets off of cold. I know that the ground is good and when I checked it with a meter it appears to be pulsing in the 5 volt range. all of the gauges were working with the old regulator. Any ideas?

I suspect that the part you received is not calibrated like your original. There is another version available that is adjustable, B9MZ-10804-EADJ.
It also might be possible to disassembly your original and separate the stuck contacts. The contacts on my 1958 Ford SW stuck, pegging all the gauges.
Tapping it freed up the contacts.

 

[Sun lover]

I was afraid that might be the case, the thought of disassembling the dash again sends chills up My spine! The engineer that designed that dash assembly hated home mechanics!