Fuel pump saga, or what am I doing wrong?
My BJ7 square body pump has been dismantles and soaked in carburetor cleaner.
Reassembled with new diaphragm, points, condenser and new gaskets everywhere.
The diaphragm has been adjusted to obtain correct point throw-over plus 2/3
turn. The respective tabs on the point set have been adjusted per the BMC
workshop manual. The check valve seats have been lapped to remove pitting at
the interface. I can see no pitting or deformities of the valve discs under
10X magnification and they appear to be flat. The pump provides no suction at
the inlet, with or without the banjo fittings. I have checked the three
chambers of the square body for integrity by isolating them and pulling a
vacuum to determine if there could be cracks in the casting itself. I have
also pulled a vacuum on the assembled pump from both in and out ports, with
the pump in any attitude to both encourage and to negate gravity with respect
to the discs in the two check valves. I can find no problem, but it still
refuses to move any fluid. I have attempted to follow all instructions
including stretching the diaphragm before setting the screws on the magnetic
housing. It cycles great, sounds like an SU pump, but still provides no
suction at the intake. What am I doing wrong?
Ken Mason
BJ7 in work
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