Rebody Anyone looked at bonnet gas struts?

Duncodin

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My bonnet is too heavy.

When I pull the lever to pop the bonnet it doesn't pop up an inch. It basically stays where it is. I can usually get round to the front and lift the bonnet but if a butteryfly farts in india (or whatever that saying is) the bonnet catch locks itself again.

I've fitted a small gas strut to the cross member in front of the radiator to lift the bonnet an inch when I pull the lever.

But my main question is about those standard struts on the bonnet hinges. They're nowhere near strong enough to hold the bonnet. I'm currently using a wooden pole but while working on the wing side mods my bonnet is up and down like a yoyo.

Anyone know of uprated bonnet hinge struts.
 

t-tony

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If the bonnet doesn’t lift at all then the bump stops aren’t adjusted correctly. Never heard of this before where the struts won’t keep the bonnet up though.

Tony.
 

Duncodin

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If the bonnet doesn’t lift at all then the bump stops aren’t adjusted correctly. Never heard of this before where the struts won’t keep the bonnet up though.

Tony.
This is the rebody forum. Always expect the unexpected.

Was fine till I put the tribute GRP bonnet on. It's MUCH heavier than the old z3 bonnet.

@Dxbolton said his struts held tribute bonnet up till he fitted the bonnet insert. Then he had to start using a broom handle. So it's not just me. Other kit builders talk about it too so there has to be a better solition.
 

t-tony

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Must be heavy, the standard Z3 lid is no light weight.

Tony.
 

Duncodin

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Must be heavy, the standard Z3 lid is no light weight.

Tony.
Actually, I don't think it's heavier. But there's a lot of material way out front. Lights, bigger grill. All that is a long way away from the struts.
 

t-tony

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That’s true. Not something you would consider unless you’re building one I guess. I suppose you need to weigh the bonnet and length from the “hinge” point to know how strong a replacement needs to be? Certainly an interesting dilemma.

Tony.
 

DaveP

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As Kaspar has said contact SGS as they can provide higher spec gas struts that will hold up the bonnet.
 

Duncodin

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That’s true. Not something you would consider unless you’re building one I guess. I suppose you need to weigh the bonnet and length from the “hinge” point to know how strong a replacement needs to be? Certainly an interesting dilemma.

Tony.
Yeah. There's a formula for working it out. Class#3 Lever IIR. Or get adjustable ones. See what SGS suggest.

I was just wondering if somebody else has done it already. I'll soldier on and take one for the team and report back.
 

Pond

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Yeah. There's a formula for working it out. Class#3 Lever IIR. Or get adjustable ones. See what SGS suggest.

I was just wondering if somebody else has done it already. I'll soldier on and take one for the team and report back.
You need to do some 'fulcrum point' maths. :)
Maybe try and find the spec of the BMW struts and go 50%, or so, stronger?

I know of someone who added SGS struts to their 250 California. He bolted them to one of the front suspension top mounts. I am going to do the same.
Not really relevant, as the cali hinges at the front on new hinges and is half the size of yours. And weighs nothing!

Or keep the lump of wood and nail a dirty great big spring on it? ;)
 

Pond

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Does the 507 use the existing two bonnet release catches?
 

Duncodin

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Yes uses same hinges, same struts and same catches.
The bonnet has nuts bonded into the grp to attach the old z bonnet pins.
Screenshot_20240614-163741_Gallery.jpg


The spring on the pins isn't really strong enough to lift the bonnet when the release cable is pulled. I hear some people swap the springs with ones from range rover or landrover or something. I just added a small strut to push it up when the release cable is pulled.

Screenshot_20240614-163620_Gallery.jpg
 

Pond

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As the 250 only uses one catch, DNA recommended pushing the 'spare' spring into the other one, which gives it more 'spring'. If a breaker on here has a couple of spare springs, you could try that?
 
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