1999 SEI186 Fuel Tank and Fuel Sender

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iantuffs

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Hello, I hope that someone can help me with what I hope is an easy fix. My 1999 Larson SEI186's Fuel Gauge reads FULL all the time when the ignition is on (drops below E when ignition is off). I have tested the gauge itself and it is functioning. So that leaves me with testing the Fuel Sending Unit. The issues is that I do not know how to access the Sending Unit itself.. There is no access that I can see. I can see in the engine compartment where both the lines and the electrics run to the tank. But they disappear into the bulk head.

Does anyone know the model number of the tank or the approximate position of the sending unit? I suppose I could drill a circle through the carpet and floor boards and then replace it with a hatch of some sort. But I need to know where the unit is located first.

thoughts?
 
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dedlund

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Hello, I hope that someone can help me with what I hope is an easy fix. My 1999 Larson SEI186's Fuel Gauge reads FULL all the time when the ignition is on (drops below E when ignition is off). I have tested the gauge itself and it is functioning. So that leaves me with testing the Fuel Sending Unit. The issues is that I do not know how to access the Sending Unit itself.. There is no access that I can see. I can see in the engine compartment where both the lines and the electrics run to the tank. But they disappear into the bulk head.

Does anyone know the model number of the tank or the approximate position of the sending unit? I suppose I could drill a circle through the carpet and floor boards and then replace it with a hatch of some sort. But I need to know where the unit is located first.

thoughts?
Did you ever find out how to access the fuel sending unit. I have the same boat and problem ?
 

iantuffs

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Did you ever find out how to access the fuel sending unit. I have the same boat and problem ?
Yes. I actually found a great pic of what is underneath the carpet. The person who originally posted this pic indicated that there are TONS of screws holding the cover on but that it was not glued down in any way. I wish I could remember where I found this pic. But I hope it helps.
 

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iantuffs

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Is the sending unit in the rear black sectjon or the front white section ?
The White Section is where the engine should be. The engine was removed. I have marked the location of the sending unit in both of these pics.
 

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JASinIL2006

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Don’t know if it will help, but here is a pic of it from my ‘97 186 SEI.
6893B270-FEE7-4BCD-A918-13C6318C5E64.jpeg
 

vorsprung

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Does anyone have a map of where the cover screws are? I believe I have found all the outside ones but I cannot lift the cover off, seems like there are some in the middle. I have a 2000 186 SEi
 

brodmann

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Sending units can be tested with an ohm meter. Once removed, hook the leads from a multimeter (set to ohms) to the two terminals on the sending unit. Some only have one terminal, if that's the case touch the other lead to the housing. Then simply move the float up and down. You should see a smooth steady change from low resistance to high resistance. Basically, the sending unit is a variable resistor. Sometimes they just need to be cleaned up. Also, the ohm range should be marked on the sending unit. Be sure you get one with the same ohms range, or you'll not have an accurate reading.
 

Scott Danforth

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Guys, this is an old thread, read the rules on posting in any thread older than 90 days unless it's your own thread
 
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