Fuel level sender

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superduty7.3

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Kubota l4400
Aug 13, 2023
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I’m new to this orange forum so I may be posting in the wrong section so hopefully someone can help. I have an
L4400h and recently the fuel gauge is stuck on full only when powered on , I want to replace the sending unit but I am told I have to buy the entire gas tank Assembly they no longer sell just a sending unit, does anybody have any information on this issue or any advice where to get this unit any help is greatly appreciated
 
TheOldHokie

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superduty7.3 said:
I’m new to this orange forum so I may be posting in the wrong section so hopefully someone can help. I have an
L4400h and recently the fuel gauge is stuck on full only when powered on , I want to replace the sending unit but I am told I have to buy the entire gas tank Assembly they no longer sell just a sending unit, does anybody have any information on this issue or any advice where to get this unit any help is greatly appreciated
Click to expand...
I can't find the sending unit in any of the parts diagrams. They only show the tank and the harness. Bizarre.

At $750 for the tank I would be seriously thinking about used or universal sending units. Or the old standby - wooden stick....

Dan
 
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GeoHorn

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Home Despot and Lowly Hardware will GIVE you a Paint-Stir-Stick that will work most excellently.

OR….. one of these…(stick it down in the tank, place your finger over the open-end, and pull it out to gauge the amount of fuel in the tank.…works like a soda-straw…. which would work just fine also.)


HOWEVER…let me add this: Most fuel sending units have a wire which goes to them which is “hot”. The circuit first passes to the sender-unit from the gauge. So, “hot” power to the gauge,…which is looking for “ground” via the sending unit.
The sending unit is driven by a float which operates a rheostat that varies the resistance to “ground”. The gauge is merely a sensitive milliamp-meter that reads the current value.
A full tank places minimum resistance and therefore the gauge reads “full”. (i.e. it’s a low-resistance circuit in that condition.) A near-empty tank places the rheostat in maximum resistance…so the gauge does not get full current….therefore reads empty.

Here’s a distinct possibility: An electrical “short” in the wire between the gauge and the sending unit is allowing the gauge to pass-thru max current…thereby reading ”Full”.

Another possibility is the float of the sending unit is “stuck” at/near the top of the tank. Disconnect the lead at the sending unit and see if the gauge suddenly reads “empty”. If so, that indicates a problem with the sending unit or float….OR…you have disturbed that electrical “short” when you moved the wire. ;)

Hope this helps.
 
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GreensvilleJay

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crazy !! I looked at all 3 versions....NO sender. Odd they don't show it attached to the tank too....
sigh...

I'd pull the sender out and bench test it.
but if the gauge says 'full'...disconnect wire and confirm gauge goes to zero. it may be a shorted wire and not a bad $1000 sender ( comes with free tank....)
 
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GreensvilleJay

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dang buried in the key/sensor drawing !
NORMAL people would think the fuel sensor would be in the FUEL TANK diagram......
yeeesh, $150 Canucks !!!

be sure to test your old unit before buying a new one though ...
 
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superduty7.3

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Equipment
Kubota l4400
Aug 13, 2023
6
0
1
Wv
GeoHorn said:
Home Despot and Lowly Hardware will GIVE you a Paint-Stir-Stick that will work most excellently.

OR….. one of these…(stick it down in the tank, place your finger over the open-end, and pull it out to gauge the amount of fuel in the tank.…works like a soda-straw…. which would work just fine also.)


HOWEVER…let me add this: Most fuel sending units have a wire which goes to them which is “hot”. The circuit first passes to the sender-unit from the gauge. So, “hot” power to the gauge,…which is looking for “ground” via the sending unit.
The sending unit is driven by a float which operates a rheostat that varies the resistance to “ground”. The gauge is merely a sensitive milliamp-meter that reads the current value.
A full tank places minimum resistance and therefore the gauge reads “full”. (i.e. it’s a low-resistance circuit in that condition.) A near-empty tank places the rheostat in maximum resistance…so the gauge does not get full current….therefore reads empty.

Here’s a distinct possibility: An electrical “short” in the wire between the gauge and the sending unit is allowing the gauge to pass-thru max current…thereby reading ”Full”.

Another possibility is the float of the sending unit is “stuck” at/near the top of the tank. Disconnect the lead at the sending unit and see if the gauge suddenly reads “empty”. If so, that indicates a problem with the sending unit or float….OR…you have disturbed that electrical “short” when you moved the wire. ;)

Hope this helps.
Click to expand...
I’m ready to purchase an aftermarket center unit although I’m told I have to get the right homes and I’m not sure how to find the correct homes that I need for my gauge on the tractor but thank you so much for your help
 
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superduty7.3

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Kubota l4400
Aug 13, 2023
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0
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Wv
superduty7.3 said:
I’m ready to purchase an aftermarket center unit although I’m told I have to get the right homes and I’m not sure how to find the correct homes that I need for my gauge on the tractor but thank you so much for your help
Click to expand...
I guess spellcheck got me on this one I meant to say sender unit and ohms
 
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superduty7.3

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Kubota l4400
Aug 13, 2023
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GreensvilleJay said:
dang buried in the key/sensor drawing !
NORMAL people would think the fuel sensor would be in the FUEL TANK diagram......
yeeesh, $150 Canucks !!!

be sure to test your old unit before buying a new one though ...
Click to expand...
Thank you for your help, please let me know what site it’s on (Coleman?)
 
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GreensvilleJay

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Greensville,Ontario,Canada
If you Google ' TC230-31202 ' you'll get lots of 'hits'. First few are vendors that sell it. Check their websites for price and shipping details. Maybe (?) local Kubota dealer as well. Mine's within walking distance so shipping isn't an issue.
 
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TheOldHokie

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