Author Topic: Fuel tank sender  (Read 1619 times)

stickandrudderman

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Fuel tank sender
« on: August 30, 2024, 07:14:21 »
I'm not an electronics expert by any stretch of the imagination but I have an idea....
Fuel level indications are rarely accurate; does anyone know how to install a transducer type sensor in the tank and convert the signal to be used by the gauge?

mdsalemi

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Re: Fuel tank sender
« Reply #1 on: August 30, 2024, 12:12:47 »
Pretty much, most fuel tank senders are various kinds of float style, where the position of the float varies resistance.

However, there’s this: Holley 19-250 Easy Level™ Fuel Level sender that uses contactless lidar (laser imaging, detection, and ranging) for detecting fuel level.

Worth a shot to play with something like this in your shop…
Michael Salemi
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rwmastel

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Re: Fuel tank sender
« Reply #2 on: August 31, 2024, 03:17:26 »
Fuel level indications are rarely accurate
Rarely accurate??  I never felt my fuel guage was wrong, and my low fuel light seemed to come on at the appropriate level.

What level of accuracy are you looking for?Do you have a need to know if there is 10.2 liters in the tank vs 10.3 liters?
Rodd

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1966 230SL auto "Italian"

johnk

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Re: Fuel tank sender
« Reply #3 on: August 31, 2024, 03:42:03 »
Mine is very inaccurate alway showing it being close to empty way too soon.
John Krystowski
Avon Ohio
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rwmastel

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Re: Fuel tank sender
« Reply #4 on: August 31, 2024, 04:25:29 »
Maybe I'm lucky.  I would trust MB to provide a reasonably well engineered system, but maybe not durable over 5 decades.  Yours is inaccurate with good parts, good wiring, good grounds, etc?
Rodd

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2006 Wrangler Rubicon
1966 230SL auto "Italian"

WRe

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Re: Fuel tank sender
« Reply #5 on: August 31, 2024, 07:08:13 »
Hi,
The fuel gauge is pretty accurate for me too. What can bother you is a dithering fuel needle, but this problem can be solved with an additional capacitor.
...WRe

AdelaidePagoda

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Re: Fuel tank sender
« Reply #6 on: September 01, 2024, 16:56:02 »
My 230SL fuel tank is reasonable accurate although there are three things that those more knowledgeable on this site may be able to provide their expertise on:

1) The gauge flickers variably, usually when the car is mobile and more vigorously when the tank is above three quarter full. Any way to stop this?
2) The tank tends to drip petrol onto the rear bumper chrome when it is full and the car is in motion. It has an original full cap with the cork O ring. Aside from not filling the tank, any advice on how to stop it leaking?
3) The red light still comes on when the petrol tanks gets to the reserve fuel level. I am amazed this still works after 60 years. Anyone else reserve light still work?

Dave
Dave
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Pawel66

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Re: Fuel tank sender
« Reply #7 on: September 01, 2024, 20:06:28 »
I would have thought:
ad. 1. You have the way to stop needle flickering described in the previous reply from WRe. It is about a capacitor soldered between the pins at the top of the fuel level sender.
ad. 2. I would suggest replacing the cork gasket on the fuel cap - a lot of discussions about it on the forum. The gasket is available from many vendors, including Mercedes.
ad. 3. Yes, it is fairly common that this light works, I think
Pawel

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WRe

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Re: Fuel tank sender
« Reply #8 on: September 02, 2024, 06:21:56 »

AdelaidePagoda

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Re: Fuel tank sender
« Reply #9 on: September 02, 2024, 20:51:27 »
Wonderful suggestions, as always. Noted and thanks.
Dave
January 1964 230SL 4SPD Power Steering
050 050 Black Soft top, Red Leather interior
Italian delivered/ Germany/ Florida/ Boston/ Sydney/ Adelaide (5th owner)

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