Experience Dealership line mechanic on MG, Triumph, Jaguar for 15 years, Instructor in commercial mechanics school 2 yr. Product information manager for piston and valve manufacture, Instructor & hotline answer man for import car parts importer 15 yrs.
Organizations Associate member SAE
EAA member
Publications Import Car magazine
Education/Credentials ASE Master Auto with L-1 certification up to 2000
Question QUESTION: My 78 MGB was running fine until the other day. Now when I put the key into the on position, I can hear the fuel pump running or pumping continuously and the car will not run. Until the other day it would run and pump for a few seconds, then it would be silent but the car would start right up. Is the fuel pump in need of replacement and if so what kind should I use and how is it replaced.
ANSWER: Hi Larry,
When an electric fuel pump on an MG runs a little and then is silent except for an occasional click it has built up the operating pressure and stopped as it should.
When a pump runs on all the time, it is normally drawing air or the line from the pump to the tank is stopped up for some reason. Not normally a bad pump.
Howard
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QUESTION: What is the best way to resolve the issue? Do I need to drop the tank and remove the fuel pump?
Answer Larry, you need to find what is wrong before you need to do much. First confirm that you have fuel in the tank. (same noise when you run out of gas) Then remove the line from the pump to the tank and put the line into a can of fuel and activate the pump to see if it is the pump or the pick-up in the tank causing the problem.
Then you will know which way to go. The pump can be disassembled if it is the pump. Sometimes one of the oneway valves can get trash stuck in it causing it to run all the time.
Howard
