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TTodd
06-19-2005, 07:04 AM
I'm haveing problems with the gauges on my 61 Lark. The gen and oil light both work but neither the heat or gas gauge work. Should there be voltage to the wires going to the sending units. Thanks Tony

61 Lark
61 Lark Cruser VIII

gordr
06-19-2005, 03:04 PM
Tony,

Provided the ignition switch is on, there should be a voltage measurable on the wires connected to the fuel level and temp sensors. The voltage might be fairly low with the sensor connected, but could be close to 12 volts with the wire disconnected from the sensor.

If you read ZERO volts on both wires, I'd suspect that the 12 volt source to the back of the two dash gauges is missing.

A pretty effective test for dash gauges is to switch on the ignition, and temporarily ground the sensor wire. If the dash unit is getting power, and is functional, you should see the needle peg out to the max position realy quick. This test is best done with a helper to watch the gauge, with instructions to call out to you once the needle approaches the "max" end of the scale. When the helper calls out, disconnect the wire from ground, as it may damage the gauge to leave it pegged for any length of time.

Incidentally, you can use your multimeter on the "ohms" or resistance function to check out the sending units. A good sending unit should show a resistance somewhere in or near the 50 to 150 ohm range, depending on fuel level or temperature of the block, in each case. If the resistance of either sender is near-zero or over 1000 ohms, I'd be inclined to regard it as faulty.

Be advised that fuel gauge problems are often due to corrosion making for a bad ground at the tank. Try running a ground wire from one of the sending unit mounting screws to a good chassis ground.

Hope this helps.

Gord Richmond, within Weasel range of the Alberta Badlands

TTodd
06-20-2005, 06:03 PM
Thanks for the advice on the gauges. I'll dig out hte ohm meter and go after it.

Tony

61 Lark
61 Lark Cruser VIII