Fuel & temp. Gauge Failure

J Lombard

I finished wiring & installing the gauges & switches in my '53 Hornet. I turned the key & the old girl came to life on the first try!!!!!!!! Now for some problems. the fuel & temp gauges just stay to the right of the gauge & don't move. Any thoughts????

J

charles4d

Crossed wires remove one on a gauge see if it move then

Glowplug

Assuming the sending units are properly connected, the loss of both gauges is most likely the lack of input voltage from the IVR... Instrument Voltage Regulator.  The IVR operates as a voltage chopper.  It creates a steady 5.7 volts by chopping the input voltage.   Make sure it is operating and is connected to the shorting bar from both gauges.  There is ONE IVR that supplies voltage to the gauge set.  If the electrical system was changed to 12 volts then you need an IVR that will drop 12 volts to 5.7 volts.  The 57-58 Ford instruments used such an IVR.  I use the later in a 1953 Wasp using OEM gauges  Last point, the IVR requires input voltage.  .

J Lombard

I guess I'll have to undo all the work I did to get that instrument cluster installed (working upside down with big clumsy hands & all those wires). Are we having fun yet!!!!!!!!!!!!!!! Oh well tomorrows work is cut out for me.

thanks guys for your input I'll let you know how it turns out

Regards

J Lombard

J Lombard

Charles, the wires are not crossed.

Ken, I have 6.3v into the IVR & 6.3v out of the IVR. I assume, then, that I have a bad instrument voltage regulator. Is there a replacement part available at Napa or due I have to look at "vintage" auto part places?

regards

J

J Lombard

Ken U, the wires from the sending units are brand new so I think they are good. I'll have to wait 'til I get back from Idaho to run the resistance test on the temp. gauge. Since I don't know how to test the fuel gauge for ground I'll just run a ground. wire from one of the screws to a solid frame ground point.

thanks for input

J

bob ward

Another thing to check is that the 2 instruments are properly earthed. Considering how the instruments are mounted their earthing is pretty much assured, but they won't read if they aren't earthed.

bob ward

For an excellent article on how the fuel gauge system works and why the gauge also needs to be grounded read FG-101 et al on mgaguru.com. It's about the Lucas system but the principals are exactly the same for the later stepdown gauges.

Glowplug

The attachment is a very good description of how the HUDSON gauges function. 

J Lombard

I am most embarrassed to answer your question but I guess I owe it to anyone following this thread to 'fes up to the problem. So here, reluctantly, is the answer. Some months ago I purchases a replacement glass front cover for the fuel/temp gauge. I replaced the old glass cover with the new one & put the gauges back into the chrome instrument cluster. When I saw Park Waldrop's picture of the instrument voltage regulator I noticed mine was upside down from his. So I took the instrument gauges out, turned the glass cover over, replaced the gauges back into the chrome instrument cluster & now the needles sit to the left of the gauges as they should with the ignition switched off. I'm sorry for the trouble anyone went to to solve this problem that really wasn't a problem.

regards to all

J Lombard

Glowplug

Jay... thanks for the update.  We are all victims of our own designs.  I can tell you that chasing the things I have done that interfere with me making progress toward my goals is a constant.  For me being able to laugh at myself is a hard fought journey.  Great to know your gauges are now working correctly.

Glowplug

failed attempt with my iPhone

Glowplug

failed attempt

RichardD

I haven't got under my dash to turn my gages the correct way yet; thinking of taking the seat out first.  The people who put the dash back together also got the gages upside down.  The temp gage is wired to be the fuel level and fuel gage wired to be the temp. I put my camera up there and took a photo of the back and it was obvious to the 'ole Hudson timers' that it weren't right. The correct back orientation is as per Park's photo. SO: I need to remove the two phillip head screws and flip it; easier said than accomplished.

BUT, an still confused on this. If I flip the gage part{containing both gages} around and install so gages won't be upside down, won't the gages be connected at the top and the end of the needles be at the bottom ??????? That doesn't seem right ????? 

RichardD

photos of gages

1st: with key turned off

2nd: Park's orientation

3rd: My gages from the back {I did NOT do the plastic terminals-so refrain.}

Geoff

If the gauges are upside down then the bar will be connecting the incorrect terminals.

J Lombard

Richard:

Don't forget when you remove the 2 Philips screws & flip it you need to flip the glass on the front also.

J