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MG Car Repair/80 mgb fuel tank sending unit wiring


QUESTION: I'm rebuilding an 80 B that someones else disassembled and in the process cut some of the wiring.  I installed a new fuel tank and sending unit.   The sending unit has one connection which appears to be for the green/black wire.  I also see a cut off black wire (ground?) coming out of the loom.  Where is supposed to be connected?

ANSWER: This is a ground wire. Originally was grounded to the frame/ body. You can find the original end of the wire you cut OR simply connect it to a CLEAN spot anywhere on the body...clean of paint and rust...undercoating etc with a sheet metal screw. That ought to work.
Good luck!


---------- FOLLOW-UP ----------

QUESTION: Brian,   Thanks, I'll make the connection as you suggest.  Also, I installed a new fuel pump.  I assume the hot wire gets connected to the white lead coming out of the loom near the pump and the black (ground?) lead from the pump can be similarly connected to a "clean spot" on the body as a ground.   Am I correct?  Thanks for your help.  Rick

Rick.  Yes you are correct. The black wire goes to ground. Originally a wire ran to a rubber sleeve -multiple bullet wire end connector some where near the pump, or in or near the trunk - where the original ground connection was made. You don't have to use this if you can't find it or even want to look. You should be fine grounding the wire to the body with a screw and loop connector end. If it were me, I'd also solder the loop connector to the wire you use. Make sure the connection to the body is clean and bright and coat with silicone grease (dielectric connector grease) after you make the connection.
Good luck!

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Brian Warmuth


General questions regarding most MG autos from 1950 through 1980 - primary are the TD, MGB, Midget and MGA.


Over 30 years of working on and restoration of MGs

Ohio Chapter New England MGT Register, AACA

BA, and MS, from WVU

Awards and Honors
several local regional awards for restorations

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