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MG Midget and Sprite Technical - Hood frame Bolts Wont Tighten

I notice that where the hinge plate for the folding hood frame is attached to the bodywork behind the door opening, several of the bolts are loose and won't tighten. I can't find how to get to the inside as it appears to be within a closed cavity, as I was thinking there were loose nuts on the back.

Can someone enlighten me to how this is fitted (or how it should be as goodness knows what po-1 did!)

Graeme
Graeme Williams

Hi Graeme,
I think the bolts tighten into a captive floating plate. Same method as used for the door hinge plates. There will be a rectangle of 3/8" thick steel plate, drilled and tapped for the fixing bolts. It is held in position against the back of the panel in a pocket made of a second piece of steel. This allows the steel plate to move a little for aligning the hinge, but remains captive in position. Chances are that the thread has stripped in the steel plate.

Tricky to get at but you might gain sufficient access through one of the cut-outs in the side of the cockpit, behind the trim panel.
Guy W

I see in the Moss catalogue there is a plate but no nuts, so I assume too that it's threaded. Is this plate free to fall inside the bodywork if I undo the bolts? It seems to be inside a totally enclosed cavitity.
Graeme Williams

Just stuck my hand up the slot on my '72 (ooh-err missus). There is a floating plate but it appears to have hank nuts welded to it which prevent it sliding out of the cage. Try new bolts, if still NBG then would a Helicoil fix it?
Bill
W Dunsmore

No, the plate wont fall down inside the body cavity if you remove all 3 bolts. It is held captive in the "cage" that Bill refers to. Usually the cage is quite thin. It may be possible to bend one edge of it back if you can get a flat bladed screwdriver to it, up inside the bodywork. Then the plate should slide out sideways.
Guy W

Or you could go to usa evil bay and get a set of scissor hinges

Prop
Prop and the Blackhole Midget

The other sort of hood, Prop.
Guy W

Looking at the Heritage site there is a panel called "reinforcing B post to wheel arch" part R10 on their listing. Moss call it a "quarter panel". There is a rough detail on that that could represent the cage everyone refers to. Is the cage on the external face or the cockpit side face? At the moment there is trim in the way and I can only remove the trim if I remove the bolts holding this plate!

I'm not that concerned about the two loose bolts - the hood stays in place on thevery few times I use it. But I wanted to remove the trim to run a wire behind it, so started tentatively to remove a bolt when I discovered two were floating.
Graeme Williams

.... also amazing what you can see in Youtube restoration videos. THe quarter panels seem to have large cut-outs just below where the plate fits so I guess you can get behind it anyway!
Graeme Williams

Graeme, that is what I mentioned to you in my first response:
"access through one of the cut-outs in the side of the cockpit, behind the trim panel."
;-)
Guy W

Yes Graeme, the bolts you are having trouble with screw into a plate held against the rear face of that quarter panel by a metal strip welded top and bottom. You may be able to get a screwdriver in to bend the retainer and remove the plate but access is tight to say the least. First problem might be getting the old fasteners out if the threads are stripped.
Bill
W Dunsmore

Oh man ....I dont envy you if those nuts are stripped greame! Goodluck!
Steven Devine

Sorry Guy! What is interesting about working on classic cars is when you come across something new it's a complete learning process so sometimes comments read at the beginning only come into context as you find out more. Not having worked on body panels the whole understanding of how it all goes together is a bit of a mystery, so as you see it was someway through before I realised about the rear quarter B post panel and the fact it is cut out in places.

AS I'm sure everyone discovers, when you need to work on a part or an area of the car you move from "ignorance" to (hopefully) expertise as a result of researching, asking questions and then doing the work. But areas you haven't touched remain a complete mystery! For me, that's about 80%!

Today I shall mainly be trying to undo the bolts, remove the trim and installing the antitheft tracker. The bolts being loose doesn't actually effect the way the hood operates as they are in shear and not tension. But I ought to get it sorted.

Steve: thanks for that! (lol!). Hope you are being over pessimistic!
Graeme Williams

LOL Graeme! I wasn't being grumpy about it! I quite agree, it often takes me several times of telling, or even looking for myself, before the penny finally drops!

Thinking about it, if your bolts are turning, but neither loosening nor tightening, then the thread probably isn't stripped after all. But if the bolts go through a plate and tighten into nuts spot welded to the back of the plate (which is how Bill describes it), then if the welds have broken the nut will just turn with the bolt without loosening.

But I suspect that the next problem is that you won't be able to remove the trim panel to reach the access hole behind it . . . . because to do so you first need to remove the bolts that hold the hinge plate!!

Oh dear, its always the "this will only take 10 minute jobs" that cause the problems!
Guy W

Guy - meet Steve, he is also a Jove's comforter! LOL

(and I know you weren't being grumpy)

I should be a font of knowledge in about 1/2 hr as I'm about to get out the spanners. The plate is available in Moss. No separate nuts are shown and the indication from the tiny sketch is that it's a threaded plate. Wouldn't that have been a cheaper manufacturing method?
Graeme Williams

You can pull the trim panel away at the bottom corner after removing a small screw and reach up through the hole in the panel.


Don't worry about the plate - just reach up and pop a 1/4 inch UNF nut on the screw thread which extends though the plate and tighten the screw while holding the nut with a 7/16 AF spanner.
Chris at Octarine Services

Sorry Graeme, should have realised you might not be familiar with the layout behind the trim panel - I've probably been looking at a bare shell for far too long. By the time I realised, you had found a photo online.

Couldn't see the part in Moss - all that is shown is the packer plate which goes between the hood frame/tonneau bracket and the trim panel. On mine the plate it all bolts to certainly feels like it has nuts welded to the back of it and Guy may well be right that these have broken away. Good suggestion from Chris to tighten it all up, surprised it hasn't been rattling and driving you mad. Hope you have small hands as access is tight. Good luck
Bill
W Dunsmore

Two bolts have come out ok. The third hasn't. Just been trying to saw the head off the last one as I can get it pulled out by about 4mm. Very cramped and small movements of the junior hacksaw being careful to whatch out I don't saw anything else in the process. Come in for a break and seen Chris's suggestion. I had ruled that out as it might damage the panel, but I'll give it a go.

I had considered cutting the trim panel away and then replacing it but it seems you can't just buy a single panel, only sets.

Off we go again!
Graeme Williams

OMG - sawing the head off a screw will bugger you up as you won't then be able to slide the plate out of its cage due to the protruding screw remnants!
Chris at Octarine Services

there's no nuts on the back - the plate is threaded. If you need another plate just ask...
David Smith

Lol - there may well be if someone else has used my trick to tighten loose screws in the past - you just cannot be sure what and what isn't there on an old car!
Chris at Octarine Services

And the prize goes to...........

********* CHRIS ************

Easy peasy when tried. Visiting local hospital later to attend to cuts and scrapes caused by wedging arm and hand where it shouldn't go but...... textbook (well, Chris's textbook) operation.

Cage? What cage? A wonderful example of PO-1 handywork, bearing in mind he was starting with a brand new Heritage shell for goodness sake!

The securing plate is a bit of 12g sheet metal with three nuts brazed on back although one has broken away (that was the cause of the problem resolved with a spanner following Chris's suggestion) and the other is presumably stripped.

Held in position with a cable tie. Brilliant!

So, I can either:
Try to buy the proper plate
Make one and get a man I know to weld on three nuts, or..
Put it back with a couple of loose nuts as suggested.

Mmmmm!

Graeme Williams

Well done that man!
Heritage shells may be different but the plate on mine is retained by a strip of metal which limits movement but holds it in place until tightened. Given that you already have had experience of nuts breaking away< I might be tempted to use a thicker plate drilled and tapped. Just need to work out how to hold it in place while you re-assemble.
Glad it was easier than we prophets of doom suggested.
Bill
W Dunsmore

Bill - you have just beaten me to it. Just had a closer look and I can see now there is a single vertical strap in the inside of the panel which would be sufficient to retain the correct plate. However, that plate would have to be tapped as standard nuts tacked onto even a thin plate would still be too thick to fit inside the strap. The extisting plate had been assembled with the nuts on the cockpit side of the plate so they bridged the strap!
Graeme Williams

My guess is that the two smaller holes are there to take pop rivets to hold the plate in place, are there corresponding holes in the rear panel?

The nuts have a ring on them which fits in the overlarge holes and then they are spot welded in place - not unusual for these to come adrift - hence the brazing repair.

I'd go for the three new nuts properly welded to the plate.

Chris at Octarine Services

Chris: one nut had a ring; one I pulled out from inside the cavity was the same and the two problem ones seemed to be a "near miss" thread.
Do you think the plate I fished out was original or has it been made up?
From what I can see, the replacement body panels come fitted with the plates and they don't seem to be available separately.
Graeme Williams

Graeme, option 4 - as I said a few posts back, I have genuine plates, from a scrap RWA shell if you want.
David Smith

Your pic is exactly as I thought it would look from feeling behind the panel so it is at least the same design as original even if it was made up later. If the shell was assembled without it it would be difficult/impossible to get into place afterwards. This is probably why it was on the wrong way round although by doing that it is not spreading the load.

Chris the two extra holes are also in the body shell but no pop rivets - look a little large for rivets. I suspect they were part of the jig to hold everything in place while the retaining strap was spot welded.

As to how you get it all back together - hmmm, ponder.
Bill
W Dunsmore

fart around with making parts or go for original parts on 'option 4' ummmm, I know what I'd do but then you'd have to ride the scorn of the engineers

if it can't be mended with blue-tac or thread lock then replace !
Nigel Atkins

I doubt if the two small holes were there for pop rivets as the whole point of the plate is that it is free to move around a bit - giving the designed for range of adjustment for the hinge.

Given the absence of a cage and the difficulty of making and fitting one to the inside of the panel, I would use the cable tie approach. Simple and effective. And once the 3 bolts are tightened its not going anywhere is it.
Guy W

Sorry David, missed that lifeline in your earlier post.
Could you drop me an email to graeme(symbol)kingshillcad (add usual uk domain ending).
Many thanks
Graeme Williams

I'd pop rivet it in! Pop rivets go up to that sort of size.

I can see no point for having any adjustment on the hinge - the original detachable hood / frame just slotted into fixed welded tubes and the MGB nuts are actually welded to the inner wing panel - no separate plate.

Chris at Octarine Services

If you rivet it in the wrong position, the header rail might not reach the screen, or may put too much strain on the frame.
Dave O'Neill2

Good for you Greame...I am surpized at how many scratches you receive to do that repair but good for you. I agree with you on the learning process...start with nothing and find your way to the end. Its always nice to have a Chris pop in and help...Its good to have friends like that!:-)
Steven Devine

The most it can be out is the width of the holes in the inner panel minus 1/4 inch for the screws diameter - so probably 1/4 inch or so.

The position of the hinges will make NO difference to the reach of the hood material to the windscreen.

Clearly the holes in the panel line up for a reason with the holes in the plate - sticking a couple of large pop rivets in to hold the plate is more likely to get the plate in the right place than leaving it to float loose.



Chris at Octarine Services

The position of the hinges WILL make a difference to the reach of the frame/header rail.

And it's not just fore and aft, up and down, there is also the rotational position.

The plate should not be riveted to the bodyshell.
Dave O'Neill2

Why rivet it AND provide two check straps?

The clearance within the checkstraps on my car is only a few mm so any plate restrained by the straps would have to be thin - too thin to be tapped. I suspect therefore that the standard item had three nuts swaged or otherwise attached to the plate. THis would mean that the item was totally locked in place by the straps. Some movement for reasons Dave suggests, but no way could it be slid out!
Graeme Williams

well I was wrong about the original plates, it is thin with captive nuts spot welded into place.
It's held in by one strap which encloses the centre nut hence allowing plenty of movement and adjustment but not removal.

David Smith

the range of adjustment is quite large, both fore-and-aft and angular - pic 1

David Smith

pic 2
you're welcome to have it if it makes life easier Graeme...

David Smith

I agree with David. The principle benefit of the adjustment - which is significant - is that it allows the bracket to rotate. And a small change in angle produces quite a lot of movement where it matters at the header rail. If no adjustment was needed, it would have been far easier and cheaper to just spot weld nuts directly to the panel and forget about the floating plate idea.
Guy W

Adjustment must be required otherwise why have a more complicated arrangement than necessary. These are hank nuts which usually have a serrated spigot which is pushed through the sheet metal and pened over to retain.

Graeme if the plate was inserted the wrong way round for the nuts to clear the strap I think it is more likely that the nut might twist out of the sheet material.

Just a suggestion but here is what I would do:

Remove the nuts from the existing plate and slide it in to the slot between the strap and the quarter panel.

Taking one of David's plates strengthen the nut attachment by welding and use this plate wrong way round as before.

Use a couple of lengths of 5/16 unf stud (or a set screw with the head cut off) with a screwdriver slot cut in the end to hold everything in place while you assemble the trim, packer, hood frame etc into position.

Once you have screw started in the third hole replace the studs with screws in turn. et voila.

Sincere apologies if I'm straying into grandmother and eggs territory here BTW.

Good luck
Bill
W Dunsmore

David: just emailed you.

Bill: my grandmother never could manage eggs so often needed teaching. I see exactly what you mean. I guess you see the original plate as a bit of packing. I'm sure the reason for failure was that there was a gap between the nut and the quarterpanel. As the bolt was tightened it tried to pull up the gap and so bent the plate. THat would have the effect of the nut needing to keep "square" as it was con strained by the bolt, and the plate bending around it. Result: nut tears out.
The packing would stop that!

But what an odd design in the first place! Why not a tapped plate and a strap a suitable distance away?
Graeme Williams

Yes, the idea is to spread the load by introducing a plate of thicker material between the nuts and the quarter panel. But actually thinking about it again the holes in the old plate are a little on the large side. It might be better to make up a new plate with clearance holes for your 5/16unf screws.
Bill
W Dunsmore

Agree with that Graeme - especially as threaded plate is used just a few inches away inside the B pillar for the door striker plate to screw into. (I use that as the excuse for me thinking the hoodframe used the same method).
David Smith

Sorted! Put in a replacement plate courtesy of David and needed to fit it the wrong way round as the plate can't be reinserted in the locating strap. And then it dawned! No spacer plate had been fitted which meant that as the bolts are tightened the nuts pull towards the bolts and because the holes in the quarter panel are so large, the nuts come through..... and pull off the mounting bracket. Fitted a spacer on the panel side with close fit holes this time. It still floats, just keeps the nuts from pulling through.

Now trying to adjust the perishing thing to get the hood aligned.
Graeme Williams

This thread was discussed between 28/02/2014 and 05/03/2014

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