An interesting theory regarding the cause of the crack of doom.
Pete Hall ……”the crack on MG roadster door,
is caused by the windscreen frame being
too close to the 1/4 glass, this puts
pressure on the door skin causing the
crack, to fix this permanently, you need
to completely assemble the doors and
adjust the fit, then undo all the
windscreen bolts, and adjust the frame
to the doors, problem solved. I have
been rebuilding MGs for over 45yrs
professionally, and I know this will cure it
the crack is NOT caused by people
pulling on the 1/4 glass frame, as
some people may tell you”
MGB tips mods and maintenance 
Agreed! …plus when you fix the crack in the door skin re-inforce it by adding a piece of metal to the inside of the skin. J.
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Sorry, didn’t mean to be anonymous, John Leeman, East Yorkshire,UK.
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Is that also characteristic for a 1980 model?
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had both doors with crack of doom. Repaired with steel backing plate, car was re painted /restored no more issues. Important to spot weld the reinforcement plate however
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It would be nice if the photo showed one more where the crack is. Keyhole images are somewhat short on visual information.
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