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Proper Wiring of Fuel Sending Unit

S

scubaman

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"My son looked in my tank but

"My son looked in my tank but put sender on properly but wiring is wrong? It is circular and has 2 green wires, 1 red and 1 black ewire. The 2 green wires are mounted in the outer circle, red is attached in the middle, and the black wire is not currently attached. LM-1 is written on the unit or LW-1. Any ideas. Thanks Tank reads empty and doesn't move"
 
"green wires are bonds. (g

"green wires are bonds. (grounds) red wire (should be pink) is sender to guage. black is ground to guage. ground the black and it should work. if not, connect the red to the black. guage should peg. if not, trouble with wiring, or guage. if so, problem with sender."
 
I connected the the black wire

I connected the the black wire (which was unattached) to the same post as the pink wire and the tank reads full which it is. Is there a problem or is the sender reading accurate? The only lettering on the sender is KM-1
 
"your guage, and wiring are ok

"your guage, and wiring are ok. however, it will always read full wired as it is. connect the black to ground. (with green ones) leave red where it is."
 
"Thanks Scott,
I connected th

"Thanks Scott,
I connected the black wire to a screw on the outer ring. Still no reading. I finally pulled really hard on the pink wire and pulled it into the post and got a reading. The bad news. The tank is definitely full but reads only 1/3 full. Now what? I wish the nearest boat dealer wasn't 100 miles from me."
 
"sender reads resistance. any

"sender reads resistance. any corrosion will have an effect. you can try cleaning it, or order sender from this site for $20-25. measure depth of tank to get best fit."
 
"be careful grounding the send

"be careful grounding the sender to earth. if you have an aluminium tank it may cause electrolysis. better to earth the black wire back to the instrument panel, then you can be sure of a good earth."
 
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