MG Car Repair: mgb fuel pump problem continues, weber carb, systematic procedure

Question
Hi Howard, I had asked you a question regarding my 1976 mgb fuel pump not working. I replaced it the other day and it started right up. I let it idle for about 15 minutes. I shut it off and it started right up. However as I started to pull out of the driveway it died. It would not start again. It cranked but would not catch. I checked and there is fuel to the Weber carb. Any ideas?
Thanks,
T. Dunn

Answer
Hi Terance,

If you had fuel up to the carburetor and it will not start, you need to not try to think what it may be that is preventing it from starting. It only requires three items to start and run. Compression, Fire and Fuel. So one or more of those three is missing. A quick test that confirms if it is Fire or Fuel is to spray starting fluid into the intake when trying to start.
Since it ran recently it is unlikely compression so you can put that aside for now. (not that it can not fail in any minute but it is least likely)

If the starting fluid makes it try to start but it will not keep running unless you keep spraying, then you have a fuel problem for sure. If you tested fuel pressure at the carburetor and it was from 1.5 PSI to 3 PSI then it is inside the carburetor what is wrong. Either water or a stuck float or a stopped up jet or something inside.

If, however, it will not try to start on starting fluid then you have lost ignition and you need to start testing there. If that is the case, let me know and I will give you a series of tests for ignition failure.

Never try to guess what is wrong. Always use a systematic procedure of testing and you can not fail to find the problem BEFORE you buy any parts.

Howard