MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - fuel problems

I am in the process of restoring a 70 MGB. the fuel pump is not working so for a while I have fitted an after market fuel pump. My problem is that when the fuel pump is turned on fuel pours out the front carby. Is the fuel pump too strong because the float level appears to be correct and new needle and seats have been installed?
C.W. Guymer

Common problem with aftermarket fuel pumps. You will need to put a regu;ator in the line and limit the pressure to about 2psi.

The noise the aftermarket pump makes 'may' annoy you in the long run!

SUs do a good job overall and are quiet.

cheers
Ian Buckley

CW - The pump should supply between 2.7 and 3.7 psi for the MGB. Ian is corrrect about the noise if you got on of the little, square, run all the time, make a lot of noise, Facet pumps, but this can be minimized by mounting it on some isolator pads. I use one for a backup pump that is permenently installed and I used a set of sound mounts that I had salvaged off of something else and I can parely hear the pump when it is running.
Good luck - Dave
David DuBois

In addition to the fuel pump, you might just want to check the front carb for proper float level and that the needle valve is correctly seating.
R. L Carleen

If the needle housing wasn't snugged down properly it can work loose and then the float can't get the needle to seal. If taping the float chamber (sharp rap with screwdriver handle) doesn't get it to stop, then pull the cover off and check for a loose needle housing or sunken float.

Even though the fuel pressure is supposed to be fairly low, The needle should still seat (for a little while) at quite high pressures. Just not reliably ;)

Mike!
mike!

Most vacuum guages also check pressure. It's pretty easy to plumb your vacuum/pressure guage into the fuel line and find out conclusively if it's putting out too much pressure. At the worst, you'd have to buy a plastic tee fitting at the auto parts store. Just know that you have 1/4" fuel line, and bring your vacuum/pressure guage along so they know what size tee to sell you.

While you're at the auto parts store, buy the fuel pressure regulator. If you find you don't need it, you can always return it later (as long as you don't open the package). If you find you do need it, it's nice to have it without having to make a second trip.
Matt Kulka

Thanks that will give me something to do this weekend
C.W. Guymer

This thread was discussed between 18/07/2004 and 23/07/2004

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.