Basszilla4
Seaman Apprentice
- Joined
- Jun 5, 2008
- Messages
- 44
Hello,
Just bought a Faria fuel gauge and Moeller three wire fuel sending unit. Having troubles getting them to work. Installed sending unit into tank. I installed fuel gauge couple weeks before along with new Faria speedometer and tachometer. Speedometer worked great. Tachometer didn't work but now does being I had to buy new rectifier. Motor is a 1973 Johnson 65hp 3 cylinder. Took boat out couple times and speedometer and tachometer work flawlessly. Just received my sending unit today and can't get fuel gauge to work.
After installing sending unit, I connected red wire to positive battery terminal. Connected black wire to negative battery terminal. White signal wire went to the fuel gauge. All instrument nighttime navigation lights are hooked in a sequence through a fused toggle switch. Tachometer and fuel gauge receive 12v power from the purple wire in control box from key switch. Tachometer and fuel gauge get their ground from same ground as lights.
First thing I noticed is my tachometer. Needle would normally rest just below the "0" reading (roughly the 7 o'clock, 7:30 position/direction) with key off. Once I turn key to the "on" position, the tachometer would "zero" out. Once I connected fuel sending units "signal" wire, my tachometer goes straight down (way below the "0") with key off. Still zero's out when key is turned on. Disconnect fuel sending units signal wire, tachometer returns to normal. Fuel gauge won't work.
So, I try to determine the problem (gauge or sending unit). Knowing the sending unit throws an ohm reading from 30 something to 200 something, I grab my digital volt/ohm meter. This is where I get completely confused. Being I am not an electrician, my volt/ohm meter has multiple settings for measuring ohms (2000k, 200k, 20k, 2000 and 200).When I turn meter on and select any ohm position, meter reads "1" in far left display. When two probes touch, the meter reads:
2000k - 000
200k - 00.0
20k - 0.00
2000 - 001
200 - 00.5
I used the 2000k position. Using any other position during testing would make meter read "1".
So, as I tested, I connect red probe to white signal wire, black probe on black "Negative" wire off of sending unit. Red wire is connected to battery's positive terminal. Kept getting different readings. Tank is roughly 1/2 to 3/4 full of gas. The readings are:
1 - Touch red probe to signal wire and black probe to sending units black wire not connected to negative battery terminal or ground., I get a reading of 092 ohms.
2 - Same as above but touch black wire and probe to ground or battery negative terminal. Get reading of 011 ohms.
3 - Disconnect red 12v wire and touch red probe to signal wire, black to negative wire and get reading of 092 ohms. Touching ground with black probe with wire does nothing to meter.
4 - Now the weird part. Red wire connected to battery +, Red probe on white signal wire, Black probe on black wire. When I touch the boat with my skin (forearm as I lean on aluminum boat) I get a reading of 194 to 210. But real jumpy. Up and down. Touch ground or negative battery terminal, then meter goes to 092 ohms.
Don't mean to be so confusing or don't even know if I am doing this test right. Being I am getting some sort of ohm reading from sending unit tells me it may be working and not sending unit at fault. Don't know how to test gauge to see if it may be at fault. I made completely sure not to touch 12v power wire to signal terminal on back of fuel gauge. Big red tag hangs off signal terminal stating not have this occur or will damage. Also, don't mean to sit here an write a novel, but just trying to give as much information as possible.
Any help would be greatly appreciated. Thank you.
Sincerely,
Errol (Basszilla4)
Just bought a Faria fuel gauge and Moeller three wire fuel sending unit. Having troubles getting them to work. Installed sending unit into tank. I installed fuel gauge couple weeks before along with new Faria speedometer and tachometer. Speedometer worked great. Tachometer didn't work but now does being I had to buy new rectifier. Motor is a 1973 Johnson 65hp 3 cylinder. Took boat out couple times and speedometer and tachometer work flawlessly. Just received my sending unit today and can't get fuel gauge to work.
After installing sending unit, I connected red wire to positive battery terminal. Connected black wire to negative battery terminal. White signal wire went to the fuel gauge. All instrument nighttime navigation lights are hooked in a sequence through a fused toggle switch. Tachometer and fuel gauge receive 12v power from the purple wire in control box from key switch. Tachometer and fuel gauge get their ground from same ground as lights.
First thing I noticed is my tachometer. Needle would normally rest just below the "0" reading (roughly the 7 o'clock, 7:30 position/direction) with key off. Once I turn key to the "on" position, the tachometer would "zero" out. Once I connected fuel sending units "signal" wire, my tachometer goes straight down (way below the "0") with key off. Still zero's out when key is turned on. Disconnect fuel sending units signal wire, tachometer returns to normal. Fuel gauge won't work.
So, I try to determine the problem (gauge or sending unit). Knowing the sending unit throws an ohm reading from 30 something to 200 something, I grab my digital volt/ohm meter. This is where I get completely confused. Being I am not an electrician, my volt/ohm meter has multiple settings for measuring ohms (2000k, 200k, 20k, 2000 and 200).When I turn meter on and select any ohm position, meter reads "1" in far left display. When two probes touch, the meter reads:
2000k - 000
200k - 00.0
20k - 0.00
2000 - 001
200 - 00.5
I used the 2000k position. Using any other position during testing would make meter read "1".
So, as I tested, I connect red probe to white signal wire, black probe on black "Negative" wire off of sending unit. Red wire is connected to battery's positive terminal. Kept getting different readings. Tank is roughly 1/2 to 3/4 full of gas. The readings are:
1 - Touch red probe to signal wire and black probe to sending units black wire not connected to negative battery terminal or ground., I get a reading of 092 ohms.
2 - Same as above but touch black wire and probe to ground or battery negative terminal. Get reading of 011 ohms.
3 - Disconnect red 12v wire and touch red probe to signal wire, black to negative wire and get reading of 092 ohms. Touching ground with black probe with wire does nothing to meter.
4 - Now the weird part. Red wire connected to battery +, Red probe on white signal wire, Black probe on black wire. When I touch the boat with my skin (forearm as I lean on aluminum boat) I get a reading of 194 to 210. But real jumpy. Up and down. Touch ground or negative battery terminal, then meter goes to 092 ohms.
Don't mean to be so confusing or don't even know if I am doing this test right. Being I am getting some sort of ohm reading from sending unit tells me it may be working and not sending unit at fault. Don't know how to test gauge to see if it may be at fault. I made completely sure not to touch 12v power wire to signal terminal on back of fuel gauge. Big red tag hangs off signal terminal stating not have this occur or will damage. Also, don't mean to sit here an write a novel, but just trying to give as much information as possible.
Any help would be greatly appreciated. Thank you.
Sincerely,
Errol (Basszilla4)
