Gauge swap.

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73c20jim

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I was using brass. Using steel is a good idea.
 

mrburitto

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  • Gas gauge accurate when stopped, but bounces while driving. Probably loos connection somewhere. Old one worked fine.
There is a pulsation dampener (a resistor actually) that bridges the two opposing coils. It's function is to control the rate of movement of the ray (needle) when the sender is generating large fluctuations in a short period of time - like going around a corner fast or slamming the brakes on. If the coil is open, or the entire ceramic plate - on which the coil is mounted - is missing, the gauge will bounce around violently.

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If you still have your original gas gauge, you might want to swap out that dampening resistor.


Awesome you just solved my problem too!
 

Matt69olds

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  • Gas gauge accurate when stopped, but bounces while driving. Probably loos connection somewhere. Old one worked fine.
There is a pulsation dampener (a resistor actually) that bridges the two opposing coils. It's function is to control the rate of movement of the ray (needle) when the sender is generating large fluctuations in a short period of time - like going around a corner fast or slamming the brakes on. If the coil is open, or the entire ceramic plate - on which the coil is mounted - is missing, the gauge will bounce around violently.

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If you still have your original gas gauge, you might want to swap out that dampening resistor.


Well crap, now I have another reason to pull the dash and replace a couple burned out bulbs!! Is this resister available from a vendor or do I need to find a good used one?
 

73c20jim

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C20 2WD Custom Deluxe. C10 2WD Base Model
Engine Size
350 CID 195/260 HP Goodwrench crate, 400 CID 2bbl
GAUGE SWAP UPDATE.

VOLTMETER

Reads 13v when ignition is on.
Reads 16v when motor is running.
Shop voltmeter shows about 13v when motor is running.

TEMPERATURE GAUGE.

Need to install correct sending unit.
Currently reads in OVERHEAT range when car is started.

OIL PRESSURE GAUGE.

New oil pressure sending unit for electrical gauge installed.
Reads 0 PSI at all times.

FUEL GAUGE

At first showed correct level and steady but bounced around while driving. Swapped resister thingy from old gauge that worked fine. Reads 0. Swapped in old gauge. Reads 0.

Working on these for three days now. Getting really frustrated. Really really frustrated.

Shouldn't the temp gauge show low even if sender is wrong?

Any help on any of these gauges will be greatly appreciated.
 

73c20jim

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350 CID 195/260 HP Goodwrench crate, 400 CID 2bbl
bump for help
 

Blue Ox

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The only thing I can offer on the fuel gauge is ours had issues with bad contact between the spring clips and the circuit board. I think it was eventually soldered, but by pushing on the dashboard / cluster you could get a reading out of it. Sounds to me like you've got grounding issues or some other contact problem.
 

bucket

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I agree, I think it's a connection problem like dirty spring clips.
 

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