merc 3.0 fuel guage not workin....im stuck

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mischief2145

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Sep 21, 2009
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replaced fuel guage last year.....new one not working.....im stuck need a wiring diagram...1992 sea pro centra............or any sugustions
 
mkast

mkast

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Re: merc 3.0 fuel guage not workin....im stuck

Have you looked at the sending unit in the fuel tank?
 
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mischief2145

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Re: merc 3.0 fuel guage not workin....im stuck

yes replaced sending unit that sits on top of tank....two wires....nadda????
 
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mischief2145

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Re: merc 3.0 fuel guage not workin....im stuck

mkast said:
Have you looked at the sending unit in the fuel tank?
Click to expand...

guage is new also....think its somewhere between tank and guage....have to test tank sending unit first to be sure its good with ohm meter
 
mkast

mkast

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Re: merc 3.0 fuel guage not workin....im stuck

Grounded?
 
Bondo

Bondo

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Re: merc 3.0 fuel guage not workin....im stuck

mischief2145 said:
replaced fuel guage last year.....new one not working.....im stuck need a wiring diagram...1992 sea pro centra............or any sugustions
Click to expand...

Ayuh,... Power goes from the keyswitch to the gauge...
The pink wire from the gauge goes to the sending unit...
The sending unit is grounded...
As the ground increases, the gauge goes higher...
Disconnect the gauge wire from the sender, 'n ground it out, the gauge should Peg, Full...
Disconnected, it should read Empty..
 
Silvertip

Silvertip

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Re: merc 3.0 fuel guage not workin....im stuck

Here is the diagram -- again! Sender resistance is 33 ohms (full), 109 ohms (1/2 full - roughly) and 240 ohms (empty). Short the "S" terminal to ground. If the gauge pegs full, it has power and ground and is ok. If not, you lost power or ground.

Gauge-SenderWiring.jpg
 
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