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MG MGB Technical - fuel pump problems

I have a '79 B that is giving me problems relating to the fuel pump. Looking at the schematics, the white wire passes through an inertia switch. Where is the inertia switch? Thanks for any help.. dave
DAVID

I have '67 BGT so I have no first hand experience with this item, but I do know that this switch is designed to cut off the fuel supply to the motor in case of a roll over or maybe a hard collision. you didn't mention what kind of problem you are having with the fuel pump, points can be prone to fail, this I know because it's happened to me. A badly clogged fuel filter can also give you problems that seem like they are coming from the fuel pump.
Jared Snider

David. The inertia switch on my car is under the dash on the driver's side, mounted on the bulkhead behind the dash. If you are not getting power to the fuel pump, this is a place to begin. A simple check is to use a volt meter to see if you are getting full power to the fuel pump with the ignition switch in the run position. If not, trace the wires back until you find the problem. Bad connections are common with older cars. Clean and try again. Pumps wear out due to burned points and the diaphram getting old. As also noted, a clogged fuel line can be a problem also. Also check that the vent line going from the tank forward to the charcoal cannister is clear. I have seen them plugged and the system would not operate correctly. Les
Les Bengtson

David
I had the same problem with my '76 B, I ran a new wire from the fuse block back to the fuel pump (by-passing the switch). This took care of the problem. May not be the safest thing to do, but it kept me on the road. Alan
Alan McDonald

Dave,
The inertia switch is located on the cockpit side of the bulkhead behind the dash, typically above your left knee when sitting in the seat. It it cylindrical, mounted with the flats on top and bottom. It should have two connectors coming out of the bottom, one with one white wire, and the other with two. The reset button is on the top of the switch.
Good luck,
Mark
Mark Rotsky

This thread was discussed between 02/12/2001 and 03/12/2001

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