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MG MGA - Inner Sill Panel

Just to follow on from my previous thread.
Did the original factory inner sill panel always have the two holes in?
Therefore if the car under inspection has no holes, the panel has been replaced?
This seems to offer some conclusive evidence if the wings etc cannot be removed.
Many Thanks
Henry

Yes, and yes.
Barney Gaylord

You've heard it from the man himself, Barney has forgotten more about MGAs than someone like me will ever know. The inner sill panels are basically flat metal except for the two holes punched in. If not interested in a coucours restoration some builders just cut the panel out of sheet metal instead of paying for the replacement piece. I personally like the idea of the closed panel, one less place for water to get into the sills, did the same on my car. You might be able to see the ends of the sill just behind the splash panels to the rear of the front wheel and the front of the rear wheel. Pry back the rubber seal and see if with a small torch you can get a view of the ends of the outer sill. You're looking for signs of rust in the lower edge area, this is where it usually starts appearing.
Bill Young

Henry,

Frank Graham's site (http://safetyfast.homestead.com/home.html) has some great photos demonstrating the replacement of both the inner and outer sills and will give you a good look at the area you are interested in.

Good luck with your purchase,

Randy Myers
'59 roadster, coupe
Randy

The two large holes are not just punched, they also have extruded edges for stiffening. They are there to encourage ventilation so the inner sill can dry out after it gets wet, therefore reducing likelihood of rusting. There should also be drian slots at the bottom of the sill assembly, which are often left out of a sill reuild.
Barney Gaylord

Hi folks. Regarding the vent and drain holes: My personal belief is that the vent holes perhaps allowed more moisture in than out, and that the drain holes soon got clogged with rust particles, rendering them pretty much useless. When my outeer rocker panels were removed, most of the bottom parts of the inner sill and sill closing plate were nothing more than air. What was left was a large heap of granular rust. When I replaced my inners sills, a friend fabricated new ones out of much heavier guage, galvanized sheet steel. After they were finally welded in place, they were drilled with several holes, and sprayed internally with dripless oil. I am fairly confident that the replacement sills will last a very long time. Well, hoping anyway. Cheers, Glenn
Glenn

It's hard to disagree with Barney, he's had his car forever and dives it in all types of weather so he should know what works to save sills and what doesn't. I don't remember right now if he ever had to rebuild the sills on his car or if it's stood the test of time. I'm still glad I sealed up the back side of mine. I punched 7/8" holes in the end caps and the A an B post internal supports before I welded them in so that I can spray waxoyl or similar inside the sills from time to time, using simple snap in plugs to seal these. It's a job I don't want to do again, but certainly won't wait as long and let the corrosion up into the posts before I do it if needed.
Bill Young

The 2 holes in the inner sill plate certainly seem like something a manufacturer would do, but then I dont expect the sills were designed to last 50 years or more. It seems more or equally important to check that the drain holes are clear.
I certainly agree with the idea of pumping them full with something like waxoyl on a regular basis. Any thoughts on what is the best substance to use?
Henry

It only seems like I have had my MGA forever, It had 150,000 miles on it when I bought it in 1977. I restored the car but didn't need to do much to the sills at the time, just one small patch on the inside panel and new outer panels. The entire body was chemically stripped and electro etched by RediStrip, down to bare steel before repainting.

While the outer panels were off the entire underbody was painted with a thin caustic etching primer and two coats of 50/50 epoxy enamel applied by brush. covering everything including the weld flanges and the inside of the outer panel. Outer panel was installed with pop rivets, not to disturb any of the paint. Holes were made in the ends of the inner sill box and top of all the pillars. Something like Waxoil was sprayed inside, and the holes were capped.

I made one little mistake at the time. When I started the project the car was barely 20 and I was 28, apparently still young and innocent and slightly short sited. I was bound and determined to put it together well enough to last another 20 to 30 years, and I did. So now it has been nearly 30 years since I started the restoration, and more than 20 years since it has been back on the road.

How time flies, 206,000 miles later, the inner sills are finally evaporating 50 years and 350,000+ miles after leaving the factory. Apparently Waxoil is not forever, and periodic reapplication may be in order. If I could turn the clocks back 30 years to do it over I would have aimed for 50 to 60 year life of the restoration. Live and learn. One thing I have learned is that it is nearly impossible to make any car survive year round driving in the rust belt for 20 years with no rust. There is still no outer body rust, just the inner sills going away.

So it appears that I will now finally have it to do over. I am going to Holland Michigan tonight to spend two days at Eclectic Motorworks in the MGA Sheet Metal seminar. I intend to learn everything possible about rebuilding MGA body sills (among other things). Plans are to tear the sills apart for rebuild next fall (starting end of November), have the body off (again) for repaint, and get it back on the road in time for next year's Spring Tune-Up Party (about April 15). Yes I know that's only 4-1/2 months, but I may be bull-headed enough to pull it off.

By this time next year my problem may be to whom to leave the car when I am gone so it may continue to be driven another 50 years through 2058 (it's 100th birthday), and who might be around then to see how well my plans for body sill preservation work out. I will at least keep you all invormed of the progress and results for the next year.
Barney Gaylord

Hi Barney. I'm sorry to hear your inner sills, like mine, finally gave up the ghost. During your rebuild years ago, it sounds like you did everything conceivable to preserve the inner sills, short of cutting them out and replacing them. It is unforgiveable that the factory did not engineer MGA sills to last longer than a palty 50 year period! What were those guys thinking anyway? I have visited the eclectic website several times and am impressed with the high quality work they do, including sill replacement, and imagine that you will thoroughly enjoy the seminar. Good luck with your inner sill replacement Barney! I bet we will see a whole new section appear on your site after your sills and paint job are done! Cheers, GLenn
Glenn

This thread was discussed between 10/04/2007 and 12/04/2007

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