fuel Gauge split screen

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markattard
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fuel Gauge split screen

Post by markattard »

Hi all would someone confirm please that the fuel gauge should read full when connected to 12v and earth on the respective terminals ?

cheers
markattard
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Re: fuel Gauge split screen

Post by markattard »

quoted from wilson auto

Using GM as an example, and many other classic manufacturers will be similar, lets discuss some of the specifics of the sender. Older GM cars from the 30s through the 60s have senders that work on a 30 ohm scale range. Zero ohms means the tank is empty and 30 ohms mean the tank is full. 30 ohms is reached when the float arm is at its maximum range of travel.

maybe its the case with splitties too?
oliver90owner
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Re: fuel Gauge split screen

Post by oliver90owner »

Look at the wiring diagram for your model. If it includes a voltage regulator it is almost certain the fuel guage will operate at the regulated voltage.
graham1957
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Re: fuel Gauge split screen

Post by graham1957 »

that is right, if you connect the tank sender terminal to ground it then should read empty. it is opposite to later cars, so in other words a wire off the sender or a burnt out sender causes gauge to read full, no stablizer is needed with these, tank sender and gauge are not interchangable with morris 1000 black face gauges, the later sender/ gauge/ stabilizer can be fitted as a job lot but not in individual components, hope this helps,mackie the collie
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pde2000
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Re: fuel Gauge split screen

Post by pde2000 »

It's not really answering the original question; does the fuel gauge read full with 12V across it? The sender is a wire wound potentiometer that has no resistance on empty, with rising resistance as it approaches full. Also there is no voltage stabiliser. But how it is wired to the gauge is another matter. Certainly it reads full when some voltage is put across it, as it is a mAmeter.
Black 4door series2 deluxe 1954, mostly original, a bit tatty but reliable runner. purchased 1996
markattard
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Re: fuel Gauge split screen

Post by markattard »

the full scale deflection on the gauge is achieved with a 400ohm resistance across terminal T and ground which sender unit should i use?
markattard
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Re: fuel Gauge split screen

Post by markattard »

anyone having a sender unit for sale with a 400 ohm full resistance for sale pls pm me thanks!
pde2000
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Re: fuel Gauge split screen

Post by pde2000 »

I just scraped the oxides off the potentiometer and it now reads 86 ohm max. It's the one that came with a second hand series II tank. If you only get full deflection with 400 ohms then it would show a less than half empty tank when full. I've lost one of the slotted screws from the rectangular lid though; vanished into the void. :oops:
Black 4door series2 deluxe 1954, mostly original, a bit tatty but reliable runner. purchased 1996
markattard
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Re: fuel Gauge split screen

Post by markattard »

oh just 85 ohms!! I wonder whats wrong with my gauge if anything is! otherwise someone might know of another type of sender unit maybe?
my tally plate attached
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