'68 Polara Fuel and temp gauge issue

[Scotty]

Hopefully someone out there has some insight on this. My fuel and temp gauge are intermittently working, sometimes when the car is started they work, sometimes it takes a little tap on the gauge cluster to get them to move, and other times both gauges start sweeping back and forth simultaneously. My first thought was a bad or loose ground connection, but the dash lights work just fine.

Also can anybody tell me what is the purpose of the electrical condenser (similar to what you find in a distributor) on the back of the instrument cluster? It appears to be connected to the fuel gauge.

Thank you all!

 

[1970cat]

check to make sure this guy is working properly. there is a way to check it with a test light but i can't remember off the top of my head what it is.

 

[67Monaco]

Hopefully someone out there has some insight on this. My fuel and temp gauge are intermittently working, sometimes when the car is started they work, sometimes it takes a little tap on the gauge cluster to get them to move, and other times both gauges start sweeping back and forth simultaneously. My first thought was a bad or loose ground connection, but the dash lights work just fine.

Also can anybody tell me what is the purpose of the electrical condenser (similar to what you find in a distributor) on the back of the instrument cluster? It appears to be connected to the fuel gauge.

Thank you all!

Ground. The lights are 12v, the gauges are 5v.

These should be the same as '68...
http://www.forcbodiesonly.com/mopar...?13685-1967-Monaco-Polara-Electrical-diagrams

check to make sure this guy is working properly. there is a way to check it with a test light but i can't remember off the top of my head what it is.

If you have an multimeter positive lead to the temp sending wire at the engine, ground to ground, with ignition on it should fluctuate between 0 and 5.25 volts repeatedly. Mine has at times shown 7 volts, just FYI, that even though 5.25v is the factory limit it may not stay in that range.

 

[Scotty]

check to make sure this guy is working properly. there is a way to check it with a test light but i can't remember off the top of my head what it is.

So I will find this voltage limiter on the back of the instrument cluster?

 

[1970cat]

Ground. The lights are 12v, the gauges are 5v.

These should be the same as '68...
http://www.forcbodiesonly.com/mopar...?13685-1967-Monaco-Polara-Electrical-diagrams





If you have an multimeter positive lead to the temp sending wire at the engine, ground to ground, with ignition on it should fluctuate between 0 and 5.25 volts repeatedly. Mine has at times shown 7 volts, just FYI, that even though 5.25v is the factory limit it may not stay in that range.

that's it ! a test light will flash when grounded and the probe touching the temp. gauge. yes it is on the back of the cluster.

 

[67polara]

I have the exact same problem with my 67, I have found that the voltage regulator that is right next to the condenser you are asking about wiggles loose. Make sure that is seated properly and it should work.

Hopefully someone out there has some insight on this. My fuel and temp gauge are intermittently working, sometimes when the car is started they work, sometimes it takes a little tap on the gauge cluster to get them to move, and other times both gauges start sweeping back and forth simultaneously. My first thought was a bad or loose ground connection, but the dash lights work just fine.

Also can anybody tell me what is the purpose of the electrical condenser (similar to what you find in a distributor) on the back of the instrument cluster? It appears to be connected to the fuel gauge.

Thank you all!

 

[Scotty]

I have the exact same problem with my 67, I have found that the voltage regulator that is right next to the condenser you are asking about wiggles loose. Make sure that is seated properly and it should work.

I can clearly see the condenser, but I didn't see the limiter. I will have get back under the dash and take a closer look.
Thank you

 

[mcmlvii]

I can clearly see the condenser, but I didn't see the limiter. I will have get back under the dash and take a closer look.
Thank you

Some voltage limiters are enclosed in the fuel gauge (as in my '66 Fury). The fuel gauge will have three prongs and not two (as with the temp gauge) if the limiter is internal to the fuel gauge.

 

[Scotty]

Some voltage limiters are enclosed in the fuel gauge (as in my '66 Fury). The fuel gauge will have three prongs and not two (as with the temp gauge) if the limiter is internal to the fuel gauge.

I'm guessing mine is inside of the instrument cluster.... I really don't want to remove that again

 

[68plymouth383]

My 68 monaco parts car didn't have a voltage limiter on the back of the cluster. It uses a printed circuit board.

 

[Scotty]

My 68 monaco parts car didn't have a voltage limiter on the back of the cluster. It uses a printed circuit board.

Oh really? Mine has the printed circuit also. Would that indicate the limiter is in another location other than inside the gauge cluster?
If anybody knows the exact location of this elusive device on a 1968 Polara I would be most grateful for that info