Steve:
This is what I am doing, I have 79 shell with a similar problem. 1.
Drill the very bottom of the crack (1/8" bit) to prevent further
propagation. Carefully align the edges of the crack, then butt weld with a
MIG from the bottom to the top. At the very top of the crack, build up a
ridge of weld on the inside of the door skin. Carefully file this ridge so
that there is a smooth transition from the rolled top of the skin to the
quarter light support platform.
If you take a look at the top of the crack, you will normally see
that it starts at the sharp transition at the edge of the rolled top.
Removing this stress riser, and strengthening this area will prevent
reoccurrence.
The cracking is caused by excess stress on the sharp transition
between the flexible rolled top edge and the rigid vent window platform.
The stress is produced by the vent window assembly sealing against the
windshield. The crack can also be caused by sitting on, or leaning against
the top of the door with the window rolled down. Correcting a misaligned
vent window will reduce the stress on the door, but the cracking appears to
be a normal result of a manufacturing defect.
Kelvin.
> -----Original Message-----
> From: Steve Murphy [mailto:k8vo@flyingbeers.org]
> Sent: Friday, December 03, 1999 1:35 PM
> To: MG List
> Subject: MGB Door Crack
>
>
> Hi,
> This has probably been covered before, but being a new
> MGB owner, and
> new to the list, forgive me for asking again.
> My new toy, a '77 MGB, is in decent original condition,
> showing 51K
> miles (with repair receipts going back to '81 to support the
> mileage.) The
> body is sound and rust free, but it has a small crack in the
> left door skin.
> I think this is known as the crack of doom... Anyways, what
> causes this and
> what is the best repair? If I have it welded, will the door
> crack again
> near the weld?
> Thanks for your help, and I'm sure I'll have more questions in the
> future!
> Steve Murphy
> k8vo@flyingbeers.org
>
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