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MG MGB Technical - Top Frame Installation

It has been a long time since I removed the top in my restoration efforts of my 77 mgb. Looking at it now I am having some difficulty understanding how it is secured to the body. I note the three holes on each side near the door opening where I believe it attaches. My questions is how does it attach? If anyone can provide a site for directions or some hints as to how to attach the frame I would be appreciative.
J Fleshman

Just three screws each side through the holes in the triangular frame plate and spacers into welded nuts on the back of the body panel. To be brutally honest I can't see where the doubt lies. There is an optional socket on a triangular plate that goes between the hood frame and the body, originally this was to install the demountable frame on early roadster as well as the tonneau bars, was retained for the tonneau bars with the later folding frames, I use them for a wind-stop behind the seats.

See http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=59204 and screw 33a pointing at the holes in the frame, and tonneau socket 47 with the same hole pattern.
Paul Hunt 2010

THANKS PAUL. WHAT CONFUSED ME IS THAT THERE ARE NO NUTS ATTACHED TO THE CAR TO WHICH I WOULD BOLT THE TOP FRAME.
J Fleshman

There should be either captive nuts or a tapped plate behind the three holes in the body. They are 1/4 UNF threads.

It is not unusual for the threads in these to be stripped and can be repaired by using helicoil inserts.
Chris at Octarine Services

Four of the six nuts had ripped away from the body on mine, the others were stripped or partially so. I found the long nuts used under the 1/4-lights are the same thread and welded three of these to a thick plate that I fitted behind the panel, one each side, with a small screw in the centre to position it while installing the frame screws. Unlike the original welded nuts this does allow the frame to tilt back and fore a bit while the main screws are being tightened, but once tightened there are several square inches of clamping pressure holding the frame still instead of a few tack-welds on the nuts, and the deep nuts resist stripping far better.
Paul Hunt 2010

I just did a mod like Paul mentions on mine where the captive nuts were missing. I put some details up here: http://www.asciimation.co.nz/pics/page21.html

Simon Jansen

And the nuts strip because the screws work loose and nobody ever tightens them. Sometimes the screws back out until the top frame shears the screws when being put down. Just like the door latch screws.

FRM
Fletcher R Millmore

This thread was discussed between 28/05/2010 and 01/06/2010

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