Advice needed on front bumper to bonnet gaps and adjustments

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ms.smally
Joined: Sat 20 Mar, 2010 19:38
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Advice needed on front bumper to bonnet gaps and adjustments

Post by ms.smally »

Hi

I am a new Z3 owner and have spent the best part of 2 days (one in pouring rain!) trying to close up the gaps between my bonnet and front bumper.

This is the best I can do:

Image

I have had the bumper off completely by removing the two hex bolts from underneath and sliding it forward off the clips under the arches. My first job was to adjust the arch clips to make sure they were as high as possible in order to draw the bumper closer to the bonnet.

When that didnt work, I removed the shock asorbers and made sure they were also adjusted to their maximum height.

It then crossed my mind that the corners of the bumper could go no higher, so perhaps it was the bonnet that wasnt sitting low enough. I wound the rubber stoppers all the way down to make sure they were not interferring with the bonnet height but still no improvement!!!ARGGGGG!!!!!

I know that there is an adjustment that can be made to the mountings using a 14mm allen key but I didnt have one handy to try. Also, it is sitting fine in the middle and it is only the corners that are problematic so I dont know how much difference that adjustment would actually make.

I really am stumped because at the edges, the clips are already at their maximum possible height and yet there is still a gap of around 1cm below the bonnet.

I would really appreciate any help or advice on this one I cant help but feel that I am missing something simple that someone else who has done the job before will think of straight away.

Thanks in advance

Helen
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Emek
Joined: Sun 31 Dec, 2006 18:45
Posts: 389

  M roadster S50
Location: Wroclaw

Post by Emek »

You must remove wheel arches more you will read here:
http://www.zroadster.net/forum/viewtopic.php?t=10847
Maybe also this will help:
http://www.rfdm.com/tis/51_11_000.pdf
ms.smally
Joined: Sat 20 Mar, 2010 19:38
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Post by ms.smally »

thank you for the pointer. I was aware of the hex bolt adjustment, but cant really see how that will help me as it only alters that height of the middle of the bumper and my problem is at the ends.

As it happens, there is virtyally no gap between the bumper and the bonnet in the mid section, it closes flush....
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TitanTim
Joined: Mon 23 Jun, 2008 18:56
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  Z3 roadster 1.9i
Location: Stafford

Post by TitanTim »

Hi Helen,

This is the gap on mine, its slightly narrower on the Drivers side than the passenger but not much,

Image

Looking at yours I don't think the gap looks abnormally wide, so long as they are even both sides and beneath the grills then will look OK. Need to be carefull you don't narrow the gap too much otherwise the bonnet might rub the paintwork on the bumper.


Tim.
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2001 Z3 1.9 Roadster Sport - 2012 Z4 sDrive 2.0 M Sport
ms.smally
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Post by ms.smally »

thanks Tim

I do think yours is quite a bit smaller than mine :shock: (oohh err)

According to the link posted earlier the gaps should be around 5mm and I think mine is nearly double that.

My husband is a perfectionist and this is almost enough to make him sell the car :bawl:

I have noticed that the bonet still has a certain amount of travel left in it and if you lean on it the gap closes beautifully but when you let go,it pops back up again.
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Canman
Joined: Tue 21 Jul, 2009 15:34
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  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

Hi ms.smally and welcome to the forum.
i recently removed my bumper for repainting due to a scuff and stone chips. when refitting the bumper it took a while to realign.
first thing i checked was the gap between the bonnet and side grill on either side. once satisfied this was equal without adjustment the bonnet must be sat straight then it was all down to bumper alignment.
if you remove the front arch liner bolts near the bumper and pull the liner back you will see there is a black plastic block which holds/secures the bumper in place at the arch. this block has slotted holes where the retaining bolts go through. so the height can be adjusted therefore closing up the gap.
sorry if you already tried this.
anyhow my gap can just be seen in this pic.
Image
Image


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ms.smally
Joined: Sat 20 Mar, 2010 19:38
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Post by ms.smally »

nice gap canman!

unfortunately those blocks were my first thought and are already all the way up. The problem now seems to be that the bonnet is not far enough down, but I am reluctant to start messing with the bonnet allignment. :(
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TitanTim
Joined: Mon 23 Jun, 2008 18:56
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  Z3 roadster 1.9i
Location: Stafford

Post by TitanTim »

ms.smally wrote:nice gap canman!

unfortunately those blocks were my first thought and are already all the way up. The problem now seems to be that the bonnet is not far enough down, but I am reluctant to start messing with the bonnet allignment. :(
Just a thought, but is the bonnet latch working correctly? or is it a bumper alignment problem?

Tim.
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2001 Z3 1.9 Roadster Sport - 2012 Z4 sDrive 2.0 M Sport
ms.smally
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Post by ms.smally »

TitanTim wrote:
ms.smally wrote:nice gap canman!

unfortunately those blocks were my first thought and are already all the way up. The problem now seems to be that the bonnet is not far enough down, but I am reluctant to start messing with the bonnet allignment. :(
Just a thought, but is the bonnet latch working correctly? or is it a bumper alignment problem?

Tim.[/quote

Actually I have just popped outside to check exactly that and I have a feeling that one side is not 'locking' in place as it should do. We might just have a breakthrough :D
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Canman
Joined: Tue 21 Jul, 2009 15:34
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  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

just a thought :idea: has the Zed got a strutt brace fitted, and if so is it catching the bonnet when shut ? As i have one not fitted at the moment as when is was on the bonnet would shut but pushed hard onto the brace and in the middle of the bonnet but due to the size/length of the zed bonnet you could still close it and it kind of flared out the bonnet near the arches leaving large gaps :head:
like i said just a thought . :shrug
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TitanTim
Joined: Mon 23 Jun, 2008 18:56
Posts: 5488

  Z3 roadster 1.9i
Location: Stafford

Post by TitanTim »

ms.smally wrote:
TitanTim wrote:
ms.smally wrote:nice gap canman!

unfortunately those blocks were my first thought and are already all the way up. The problem now seems to be that the bonnet is not far enough down, but I am reluctant to start messing with the bonnet allignment. :(
Just a thought, but is the bonnet latch working correctly? or is it a bumper alignment problem?

Tim.[/quote

Actually I have just popped outside to check exactly that and I have a feeling that one side is not 'locking' in place as it should do. We might just have a breakthrough :D
Thats great Helen, keep us posted :lol:

Tim.
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2001 Z3 1.9 Roadster Sport - 2012 Z4 sDrive 2.0 M Sport
ms.smally
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Post by ms.smally »

no strut brace but good thinking, I have had that problem with other cars in the past, the clearance can be minute.

I am hoping the main problem can be rectified with a new 'springy bit' for the bonnet catch. I will be checking it first thing and will let you know how I get on.

Thanks for your help and for making me welcome.

Helen
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Canman
Joined: Tue 21 Jul, 2009 15:34
Posts: 1199

  Z3 roadster 1.9
Location: Rotherham

Post by Canman »

ms.smally wrote:
Thanks for your help and for making me welcome.

Helen
your welcome :wink:
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Please help. The money will go to a good cause. email me for the link to my fundraising page.
Malcolm E Zed
Joined: Mon 15 Feb, 2010 19:57
Posts: 490

  Z3 roadster 1.9i
Location: Manchester

Post by Malcolm E Zed »

Not been crashed has it?
paulb1976

  

Post by paulb1976 »

Just tweaked my bonnet shutlines the other day - Silly question but have you adjusted all four bump stops and not just the two on the slam panel ?
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Deano1712
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Joined: Sat 05 Aug, 2006 12:56
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  M roadster S50
Location: Leeds

Post by Deano1712 »

The way I did the adjustment is as follows:

1. Remove the two catches that hold the bonnet down (you may be able to just de-activate them by wedging open the bonnet release lever.

2. Put a blob of vaseline onto the heads of each of the 4 rubber stoppers. Lower the bonnet gently and see whether all are touching the bonnet. You will see this from the vaseline. If a blob is not squashed the stopper is low.

3. Adjust the stoppers until all are touching the bonnet equally.

4. Push down on the bonnet and measure the gaps to the bumper.

5. Adjust the stoppers until you get the gap you need. Make sure you press down on the bonnet firmly, since the catches do this when they are set right. If the gaps are large all the way along you need to turn 4x the stoppers equally. If the gap is high on one side you adjust the stoppers in proportion.

6. When the gap is set you need to set the catches so they are BOTH pulling the bonnet down. Screw both catches up into the bonnet so they are not engaging.

7. Keep lowering one catch a half turn at a time until it just catches when you drop the bonnet. Screw that catch one turn back into the bonnet so that it no longer catches.

8. Adjust the other catch half turn at time (as above) until is just catches. When this is done lower the other catch one full turn.

9. You should then have both catches engaging correctly and the gaps set right. :)

I dont know why you tried to adjust the bumper. Its the bonnet that has the adjustment.
Last edited by Deano1712 on Wed 14 Sep, 2011 13:53, edited 1 time in total.
Z3M with a few mods...and a little bit more power
ms.smally
Joined: Sat 20 Mar, 2010 19:38
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Post by ms.smally »

Hi all

Day three of messing around and I think some progress has been made. One of the bonnet catches was missing a bit and so not engaging which didnt help but we have been round the houses doing all the relevant tweaks and have gotten things tidyed up considerably.

Here is how we ended up
Image
still around a 6mm gap which is bigger than ideal but not too bad.
Thanks for the tips
Frank.A
Joined: Mon 20 Jul, 2009 21:15
Posts: 875

  Z3 roadster 2.8
Location: Twixt York and Hull

Post by Frank.A »

According to the information on shut lines in TIS,the bonnet/front bumper trim gaps are 5mm +1/-0.5mm.

So what you have achieved is within tolerance.Well Done. :)
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ms.smally
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Post by ms.smally »

Deano1712 wrote:The way I did the adjustment is as follows:

1. Remove the two catches that hold the bonnet down (you may be able to just de-activate them by wedging open the bonnet release lever.

2. Put a blob of vaseline onto the heads of each of the 4 rubber stoppers. Lower the bonnet gently and see whether all are touching the bonnet. you will see this from the vaseline. If a blob is not squashed the stopper is low.

3. Adjust the stoppers until all are touching the bonnet equally.

4. Push down on the bonnet and measure the gaps to the bumper.

5. Adjust the stoppers until you get the gap you need. Make sure you press down on the bonnet firmly, since the catches do this when they are set right. If the gaps is large all the way along you need to turn 4x the stoppers equally. If the gap is high on one side you adjust the stoppers in proportion.

6. When the gap is set you need to set the catches so they are BOTH pulling the bonnet down. Screw both catches up into the bonnet so they are not engaging.

7. Keep lowering one catch a half turn at a time until is just catches when you drop the bonnet. Screw that catch one turn back into the bonnet so that it no longer catches.

8. Adjust the other catch half turn at time (as above) until is just catches. When this is done lower the other catch one full turn.

9. You should then have both catches engaging correctly and the gaps set right. :)

I dont know why you tried to adjust the bumper. Its the bonnet that has the adjustment.
I already have the 4 rubber stops turned as far down as they are possible to go so I dont see how the bonnet could get any lower.
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zedder3
Joined: Thu 15 Oct, 2009 09:03
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Post by zedder3 »

This is really interesting as I've nearly posted a few times about this. The driver's side of mine has a larger gap than the passenger's side. I wasn't sure how to fix it but will try some of the things mentioned here. Hope fully I will be able to sort it!
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c_w
Joined: Thu 19 Aug, 2004 16:50
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  M roadster S50

Post by c_w »

ms.smally wrote:
Deano1712 wrote:The way I did the adjustment is as follows:

1. Remove the two catches that hold the bonnet down (you may be able to just de-activate them by wedging open the bonnet release lever.

2. Put a blob of vaseline onto the heads of each of the 4 rubber stoppers. Lower the bonnet gently and see whether all are touching the bonnet. you will see this from the vaseline. If a blob is not squashed the stopper is low.

3. Adjust the stoppers until all are touching the bonnet equally.

4. Push down on the bonnet and measure the gaps to the bumper.

5. Adjust the stoppers until you get the gap you need. Make sure you press down on the bonnet firmly, since the catches do this when they are set right. If the gaps is large all the way along you need to turn 4x the stoppers equally. If the gap is high on one side you adjust the stoppers in proportion.

6. When the gap is set you need to set the catches so they are BOTH pulling the bonnet down. Screw both catches up into the bonnet so they are not engaging.

7. Keep lowering one catch a half turn at a time until is just catches when you drop the bonnet. Screw that catch one turn back into the bonnet so that it no longer catches.

8. Adjust the other catch half turn at time (as above) until is just catches. When this is done lower the other catch one full turn.

9. You should then have both catches engaging correctly and the gaps set right. :)

I dont know why you tried to adjust the bumper. Its the bonnet that has the adjustment.
I already have the 4 rubber stops turned as far down as they are possible to go so I dont see how the bonnet could get any lower.
Because to a degree I'm sure the 2 catches can also affect the bonnet height, so it may not even be on the buffers if the catch isn't adjusted down a bit.

However, due to the design, it is not BMW's best in terms of ideal shut lines. I've seen very few Z3s that look "perfect".
paulb1976

  

Post by paulb1976 »

After all this I've decided to have another go at tweaking my bonnet and managed to split the rubber adjuster at the front :head: that'll teach me to leave well alone - Anybody know the partcode for the front adjusters as the ones shown on realoem look like they have the little plungy bits ?
ms.smally
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Post by ms.smally »

paulb1976 wrote:After all this I've decided to have another go at tweaking my bonnet and managed to split the rubber adjuster at the front :head: that'll teach me to leave well alone - Anybody know the partcode for the front adjusters as the ones shown on realoem look like they have the little plungy bits ?
lol I'm causing trouble already, always knew I was a bad influence :devil:
paulb1976

  

Post by paulb1976 »

I've just a touch of OCD i think :)
billy56
Joined: Fri 29 Jun, 2007 20:14
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  Z3 roadster 1.9
Location: larne

Post by billy56 »

Our,s are very good! but doe,s it really matter?
The Z3 is a toy along with thing,s like motorbike,s and old landrover,s :wave
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Robert T
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Location: Cheshire

Post by Robert T »

paulb1976 wrote:Anybody know the partcode for the front adjusters as the ones shown on realoem look like they have the little plungy bits ?
I think you mean part #24 on the diagram below:

Image
Engine hood/mounting parts - BMW parts catalog

However, AFAIAA the adjustment is on the catch (part #11) and not on the rubber stop. The pin part has a thread on it and a can be screwed in or out - there may also be a locking nut on it which has to be undone first - I'd have to look to check, but it is pretty obvious how they work.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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Mike Fishwick
Joined: Fri 19 Jun, 2009 10:27
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  Z3 roadster 2.8
Location: Daglan, France

Gaps

Post by Mike Fishwick »

What size gaps are you aiming for? BMW specify 5 mm.

And yes - the bumper height can be adjusted, by a T50 torx key applied on a long extension from the bottom of the front apron, after removal of the bumper securing bolts with a 17 mm socket.
paulb1976

  

Post by paulb1976 »

Thanks Robert T , parts now ordered although the old ones seem to be welded in place nothing a screwdriver can't sort :)
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