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I assume since the rally gauge is back lit, there is no way to make it brighter? I have the aftermarket rally gauge and even with LED's, it can hardly be seen in the dark. I was considering trimming down the sides of the face, and angling some aluminum tape to possibly brighten the face... Any other ideas would be appreciated.
Here is the gauge.
The pictures below show where the illumination bulbs are...
I'll ask the obvious since it may be overlooked. The car is 55+ years old. During this period of time it's possible a PO has replaced the original bulbs with the incorrect bulbs. First, double-check the bulb part number(s). There were several aftermarket manufacturers who made instrument cluster/gauge bulbs. There is a table in the CSM which identifies each bulb by operation/function & part number. It is quite possible the incorrect bulbs/lamps are installed. I'd validate the OEM bulb/lamp part number first off.
Ken- I HAVE searched the forum. I didn't find anything related to the 68-69 rally gauge. I search every time before I post. Unless it's worded differently, I have searched for "aftermarket rally gauge brightness", "rally gauge LED's", and several other searches.
I will also add, since I don't know what type of repro it is, the face is steel- the fuel, temp, and oil gauges do not have any plastic... So the ONLY light would be reflected off of the white painted sides of the gauge...
The other thing, which comes to mind esp. since you have no indication of manufacture, etc. are you testing this pod on the bench? I'd test it on the bench direct w/ a battery. Curious about requirements for wiring of that gauge pod - resistance, wire gauge, etc. Any 'other' aftermarket type gauges pods with suspect wiring in the instrument cluster panel. Wiring can make a difference.
Look at the back of the black trim ring that goes behind the clear lens. Most reproductions come painted black on both sides. The back side of that ring needs to be painted white, or light aqua to reflect light on the face. This is a photo of a 68 tach, but the gauge pod has a similar ring. The part I am talking about is in the lower right corner.
Before tearing into the gauge pods, are you SURE you are getting full voltage on the illumination circuit? Forgive me for asking the obvious, but is the rheostat in the headlight switch turned all the way to the fully bright position? Is the rheostat even making contact correctly (the wiring on the variable resistor does get corroded over time)? Did you check voltage at the 4A INST LPS fuse to verify it's 12.5V? How about at the grey illumination circuit wire at the instrument pod connector. And let's not overlook the other side of the circuit - are the ground straps correctly installed and making contact to clean metal? Have you pulled the pods out of the car and tested brightness on the bench in the dark?
Hi Joe,
Yes- I am getting full voltage from the headlight switch. Ground strap is good and grounded. Speedometer and tach are VERY BRIGHT. The bulbs are BRIGHT in the housing.. Just not reflecting enough light onto the face.. I can see both bulbs illuminating brightly, just not enough light reflected onto the gauge face... I am going to bench test it this weekend. I am also going to check if that ring is painted. Maybe I should go with a bright silver if it isn't painted white or light blue.
This morning, I used aluminum tape- used for HVAC, and lined the inside of the gauge pod, the backside of the ring, and a few other areas... WOW! Gauge is absolutely 100% BRIGHTER! Clear as day now.
This morning, I used aluminum tape- used for HVAC, and lined the inside of the gauge pod, the backside of the ring, and a few other areas... WOW! Gauge is absolutely 100% BRIGHTER! Clear as day now.
