Brace across rear turrets +2S

I have another minor irritant on my hands, and need some guidance please:

In front of the fuel tank, behind the rear seats, is a wide brace across the body, bolted to the turrets (Spyder chassis) with large ½" bolts. Are the nuts in the turrets captive or loose?

One bolt wound out without any trouble, but the other is not doing anything and I fear, but hope not, a cross thread.

Thanks
Hal

Do they bolt to the chassis or bobbins in the body?

I have a sypder frame waiting to be fitted and I don’t see any fittings for the cross brace. They normally don’t use captive nuts for the body fitting but as steel plates that you drill and thread due to body variation.

My standard they are captive / part of the chassis.
I remember that chassis twist affects the alignment of these bolts and can cause one to be cross threaded.
I can’t remember, but the car either needs to be on its wheels or jacked under the diff. One of these positions will make the brace fit perfectly, one will be a fraction out.
Maybe you could use this to your advantage to get the bolt out and then helicoil.

Is the bolt turning and not coming out or cant be turned ?

As other have said the bolt goes through a bobbin in the body and into the threaded reinforcing plate on the chassis which is drilled and tapped to fit the body bobbin location.

If the bolt turns but does not come out the threads of the bolt or the threads in the chassis plate may be stripped. Try a little gentle leverage under the head of the both with a small screw drive as it is turned to help it get a grip on any remaining threads and start to come out.

cheers
Rohan

Thanks Rohan

The bolt is turning but not coming out. I think it must have been cross threaded way back, as there was no resistance when I first attempted removal.

Could this bolt be left in its present state for light road use - noting that the other bolt is good - without upsetting any geometry any more than it might already have been? I think I’d prefer to tackle this in the winter during the planned chassis/engine removal.

My question would be why do you need to take this brace panel out?
I see in another thread you have one of Andy at Axminsters nice new tanks so the thought has occured to me, and I am probably teaching you to suck eggs here, if you are aware that tank removal is usually done through the boot and then there is no need to touch the front brace at all.

Alan.

Hi Andy - a valid question! I understand, and have installed, the tank from the rear. However, I had to make a small adjustment underneath and needed the tank to tilt forward ever such a small amount, saw the brace was only fixed on with two bolts and thought for the two minutes required to undo it ’ how easy can this be’… :unamused:

I’d say if you can get the bolt out using Rohan’s suggestions, give it a try. You may get lucky and find that a new bolt and chasing the threads with a tap will fix it.

I had similar a similar when I did my tank, but removing that brace makes things a whole lot easier. I’d do it the same way again.

I would, however, put both bolts back in as soon as I got the brace off.

Tom

The bolt acts in shear to prevent the strut top support leg moving by linking the two suspension legs together. There should be no problem with the bolt in place for normal road driving and it not properly clamping the body to the chassis . You may get some squeaks as the leg and body move relative to each other over bumps if the body is not clamped to the leg as intended

cheers
Rohan

I would drill it out starting with small dia.
Good luck
Alan

Hi Hal

If it turns easily you could grip the head with mole grips and twist and pull to get it out enough to continue with
to Rohans method

Good luck

For me the bolts were longer than needed leaving exposed threads to rust inside the box section of the Chassis.
When you tried to unscrew the Bolts the threads got stripped. Now you have the end of the Bolt with rusted thread inside box section stopping removal.
10 minutes with some decent Twist Drills and Mole Grips on Bolt Head.
Job done.
Alan

Thanks everyone, again!

I did manage to get the bolt to bite by applying some serious pressure behind the brace with a pry bar, as Rohan suggested, so at least it shows the hole is not elongated which was my main fear.

I take it that the plate you refer to is in behind the spring at the top of the turret? - another question: Is there anywhere an exploded view of the Spyder chassis?

We are now in serious lockdown in France, so the likliehood of driving around the B roads this spring and summer is fading fast, so I am wondering if I do not incorporate plan B, the winter project, and lift out the engine and chassis and give it a good workover.

The tapped plate is welded to the front of the chassis suspension support leg directly behind when the bolt goes through the cross brace and the body bobbin into the the plate. It sounds like the bolt is stripped where it engaged the plate but the plate tapped hole probably OK.

cheers
Rohan

Ugh - that I did not want to hear! - ‘plate welded to chassis’ - so it is not straight forward to replace (Even if there is some bite in the threads, the likliehood is not much). I do not like helicoils in ‘thin’ plate.

How thick is said plate anyway?

From memory its about 5 mm thick plus a couple of mm of the suspension leg material for the thread length of about 7 mm. If the threads are substantially damaged then helicoil or solid thread insert or drill and tap it out to the next largest size. The bolt works mainly in shear so the clamping load does not need to be high so the thread length is OK even if a bit shorter than desirable

cheers
Rohan

Here is a picture of my Spyder chassis looking towards the rear cross member. You can see the two holes for the cross brace at the top of the turrets above the springs. You can just about see the plate which the hole is drilled in; it is (IIRC) about 4mm thick on top of the turret. Hopefully the thread is OK and just needs a clean up by running a tap down it. If you don’t have a tap then file a flat or two and a point on a bolt an use it with lots of lube. If the thread is gone then I’d see nothing wrong in drilling it and the bobbin hole bigger, then running a tap down the next size up so the bobbin and chassis are both tapped. For a helicoil you’d probably need to move the body out of the way but you may be able to pop one in the chassis - use some locktite to fix it in place mind. You could run a long helicoil through the bobbin as well but I suspect it would snap if the body shifts slightly, so probably best just to helicoil the chassis.

Sorry Matt but
Never ever use Loctite on Helicoils that’s a no no. Also clearance hole in Bobbin, only Tap Chassis.
Alan

Interesting, my Spyder chassis doesn’t seem to have any thing for that bolt…

Maybe there enough thickness there or something in the tube to drill/thread. There is a lone spot weld on the tube.

Mine’s an early chassis (#250 IIRC) and I’m pretty sure it had a plate but I may be mistaken - the body’s sitting on the chassis ATM so its hard to check…