[Bodywork] issue with mounting the hood / bonnet

[thomas_m535i]

Ok, so I'm trying to install two new torsion springs (see link 1, items #6 and #7) which go inside the tube (item #4) at the front of the hood.

This goes without any serious hassle. However, when I pull the release cable and the hood is released, I find that the force by which it opens ('pops') is not strong at all. It only opens for a small bit.
This is nowhere as it should be and used to be before the restoration.

I figured the torsion springs might benefit from another turn to increase the tension which could make the hood open further probably. But to do this would really take serious/extreme force (even needed to make a special tool for my attempt).

I'm wondering if I'm installing the torsion springs the wrong way or that it's indeed normal to make another turn. I don't have the old hood or torsion springs anymore.

If you have any ideas about this, please let me know .


1) http://bmwfans.info/parts-catalog/E12/E ... ing_parts/

[Lenny D.]

Over the life of my E12, including replacing the hood I have found that periodic lubrication of everything that moves is essential to that original 'pop'.
Just follow the movement as you press the hood as if to close and observe the movement of everything. A few drops of motor oil in a controlled oiler is fine, particularly No. 4 in the diagram. It slides in and out for the operation of the opening and closing of the hood.

[thomas_m535i]

Thanks Lenny. I agree that lubrication of the hood related parts is certainly important. However, all those parts are new and move without too much effort if you move them by hand.

In this case it's rather that these two springs don't seem to 'push up' the hood (on release) with enough force... so the hood therefore only pops up quite slowly and not the whole way that it should.

Any ideas?

[Mike W.]

I would guess you need more preload. And be careful with your fingers, they are fairly strong springs with no leverage on them, which is why they work, they're strong.

[thomas_m535i]

Thanks Mike.

It was a lot of fiddling with removing and remounting the hood/bonnet, but the solution was to turn the plates (item 2 and 1 in my example) at the tube (item 4) and also the torsion springs.

After a couple of tries, it now looks like it has enough preload (to keep the hood in the air at the front). The hood lock is not yet fitted, but it will probably pop nicely now .