Fuel Gauge Sender Unit
Posted: Thu Feb 26, 2009 7:03 pm
I read with interest the previous posts on this subject by 'bollicky' to rectify problems with the fuel tank sender..it was very detailed however in the underlined extract from his description
right then first i tried running an additional earth from the terminal block to the engine so the best there is. Result fuel gauge reading empty indicating an open circuit as if you short the 2 wires going back to the instrument panel you will get a reading of full. stay with me.
I went on after testing the loom wiring yet again as above,to removing the sender unit and took it to the shed for some intimidation.
I cleaned the terminal block spades until they shined and also carefully dissassembled the variable resistor housing and cleaned the contacts with a cotton bud.
After putting it back together I found i got a good reading on my multimeter varying with the movement of the float as you would expect.
Put it all back in the van same reading as before EMPTY!
Took it out again and removed the terminal block by drilling its mounting rivet out .Attatched a wire for ground to the sender/float housing mounting screw and resoldered a new longer wire from the resistor housing.
I then passed the two wires through the small hole left by the origional terminal block and crimped some spade connectors on, then covered the opening with araldite to make a good seal.
I had already cut off the origional female connector on the loom so made neat with insulation tape and a cable tie.
Result perfect reading
Looking at the terminal block from the top of the sender assembley that I removed I see that the earthing is made by the plastic sandwiching a metal plate to the metal surface via a rivet,dirt/corrosion and sealiing gunk was evident under this so no way was a descent connection to the other end of the resistor ever going to be made for the blocks spade.
Running out of puff now how many chapters is that. hope it makes sense.
Took some pics too.
Does this mean he/you connected the two 'new' wires from the sender to the two old wires coming from the wiring loom..the new live to live and the new earth to the other??? I know this is a stupid question, but I wasnt sure if the new earth should be be fixed to the sender plate or similar earthing point
right then first i tried running an additional earth from the terminal block to the engine so the best there is. Result fuel gauge reading empty indicating an open circuit as if you short the 2 wires going back to the instrument panel you will get a reading of full. stay with me.
I went on after testing the loom wiring yet again as above,to removing the sender unit and took it to the shed for some intimidation.
I cleaned the terminal block spades until they shined and also carefully dissassembled the variable resistor housing and cleaned the contacts with a cotton bud.
After putting it back together I found i got a good reading on my multimeter varying with the movement of the float as you would expect.
Put it all back in the van same reading as before EMPTY!
Took it out again and removed the terminal block by drilling its mounting rivet out .Attatched a wire for ground to the sender/float housing mounting screw and resoldered a new longer wire from the resistor housing.
I then passed the two wires through the small hole left by the origional terminal block and crimped some spade connectors on, then covered the opening with araldite to make a good seal.
I had already cut off the origional female connector on the loom so made neat with insulation tape and a cable tie.
Result perfect reading
Looking at the terminal block from the top of the sender assembley that I removed I see that the earthing is made by the plastic sandwiching a metal plate to the metal surface via a rivet,dirt/corrosion and sealiing gunk was evident under this so no way was a descent connection to the other end of the resistor ever going to be made for the blocks spade.
Running out of puff now how many chapters is that. hope it makes sense.
Took some pics too.
Does this mean he/you connected the two 'new' wires from the sender to the two old wires coming from the wiring loom..the new live to live and the new earth to the other??? I know this is a stupid question, but I wasnt sure if the new earth should be be fixed to the sender plate or similar earthing point
