Mystery breakdown

[morrisminor]

Just been for a 25 mile run, ran perfectly,  1 mile from home,  cough, splutter, it cut out refused to start,  checked gap on points,  swapped rotor and condenser separately, checked there was fuel coming through,  jets clear, it started,  half a mile later the same thing ! Primed fuel pump again off we went , anybody had anything similar ?

[Howard Wright]

Hi Morrisminor

Yes!  In my case I found it was a bit of dirt in the fuel pipe, too big to go into the carb but big enough to stop the flow.  The annoying thing was that when you stop, the offending bit floats back down the pipe a fuel “seems” to flow normally.  A few miles on it gets sucked up and blocks the pipe again.

Hope you find the fault?

Cheers

Howard

[morrisminor]

Annoying isn't it Howard,  was your fault the pipe from pump to carb or tank to pump ? 
How did you clear it ?

[bob46320]

Do you have substantial play in the top bush of the distributer. I did, and it caused a similar problem. Once the engine was nice and warm, the points gap reduced to a stage that they didn't open. Also check your points are clean, I once had a problem where the engine would start, run but after several miles would all but stop. Had to get towed home, and after cleaning everything fuel wise found pitted points - How embarrassing !

[Howard Wright]

Hi Morrisminor

From the pump to carb. It got so bad that eventually the offending bit got lodged in the entrance to the float jet (SU. Carb) Eventually simply blowing the float jet backwards cleared the problem.

Good luck

Howard

[Ian Williams]

I have had a porous chamber on an AC fuel pump cause similar problems.