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MG MGB Technical - MOT failure ?!

Yesterday my 1979 BGT failed the MOT test. Reason given is "deliberate modifications to outer sills, not seam welded".

The modification that the tester has referred to is at the bottom of the rear wing, in front of the rear wheel (the area that would usually be repaired by fitting a quarter wing repair panel). I discovered some minor rust spots in this area when the car was about five years old, and in a couple of places it had pin-holed through. I cut through the outer wing with a 1" hole saw and then opened this up to a 2" x 4" hole which allowed me easy access to clear this area of rust and debris. After applying Waxoyl I made a steel cover plate and fixed this will self-tapping screws and painted over the area with underseal. Since then I have removed the cover plate every 2 or 3 years to check for rust and re-apply Waxoyl where necessary. This area of the car remains rust-free and the cover plate, although not hidden by the underseal, is not noticeable as it is within the 4" wide strip of undersealing which I have applied along the sill area.

The MOT tester has declared that this part of the rear wing (which he calls "outer sill") is load bearing (ie, within 30cm of (a) seat belt lower mounting, and (b) rear spring hanger) and because of this the cover plate should be continuously seam welded, not screwed. I argued that this area is not load bearing and that structural integrity is provided by the sill which is behind this part of the rear wing.

Since I did this modification in 1985 the car has passed 16 MOTs (with six different testers) without any criticism or comment regarding the mod.

Before I put my money where my mouth is and lodge an appeal, can anyone out there confirm whether or not this part of the car (lower rear wing) is classed as load bearing (for the purposes of MOT)?
Brian Shaw

Brian. This problem really needs to be addressed to either the MOT itself or to a competent automotive engineer with chassis design experience and familiar with MGBs. Certainly, no one would be willing to cite an internet bulletin board, populated by a number of people of unknown qualifications, as a primary reference source in any legal matter. Might it not be easier to simply find another inspector to perform the inspection? Les
Les Bengtson

The tester is wrong. The rear wing is the same as the front wing (which was attached with bolts from the factory, point out to the tester) from the factory. You may have to get a statement from an 'expert witness' like the MGOC or MGCC before he believes it. Both my V8 and roadster passed at least one MOT with corrosion in the rear wing panel before I replaced them.
Paul Hunt

Strange one this, He may be right but his wording might be wrong. My MGA failed on the inner sill of the body being slightly rusty. The car has a frame so the body is not a load bearing item, it also has no seat belts, but as the rust was within a certain distance of the frame failed its mot. If the hole you have in the wing was round and had a grommit/bung fitted, like the midget, then it would probably pass, crazy.
Tatty

Likewise my V8 *did* fail on a hole in the inner wing, precisely where the holes for the RV8 manifolds are cut.
Paul Hunt

Thanks for all the comments and opinions.
I have submitted an appeal form and the car will be re-tested by an inspector from Vehicle Inspectorate on Friday this week.
Brian Shaw

The car was re-tested yesterday and was failed again on the same point. The re-test was carried out by two inspectors from the Vehicle Inspectorate, accompanied by the tester who failed the car originally. The lead VI inspector conceded that my modification did nothing to weaken the car's structure but it still constituted a fail because the hole in the wing is within 30cm of the rear spring mounting point and also the seat belt anchor point.

I was told I needed to patch over the hole with a sheet steel patch continuously welded around the edge.
The original tester said that if I fitted oversills (stainless steel type, or even plastic) the car would pass because he wouldn't be able to see behind the oversill.

I asked the VI man to comment on the fact that the modification was done 16 years ago and had passed every MOT since. All he could say was that "the other testers must have overlooked it".

The nearside rear wing has three 1" holes cut, with rubber plugs fitted. I was told that this was also a reason for failure and that they would have to be welded up.
Brian Shaw

This thread was discussed between 27/07/2002 and 03/08/2002

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