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Boot Trunk Mechanism

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JohnRogers
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Boot Trunk Mechanism

Post by JohnRogers » Mon Dec 14, 2015 2:12 pm

Boot Trunk Mechanism
Unfortunately while I was prepping the car to go to Goodwood this weekend the wind caught the Boot / Trunk lid and moved it open – at which point there was a fairly loud crack.
Of course I knew what was likely to have happened. I have read through the main postings on this at

viewtopic.php?t=3367&highlight=
These are main details from Chris which he posted in 2006.

The posting about Brucey’s special tool posted in 2013 are at
viewtopic.php?t=19379&postdays=0&postorder=asc&start=15

Below is an image of the current situation in my car showing “pointâ€
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Pod
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Post by Pod » Mon Dec 14, 2015 2:42 pm

John, Have you tried doing it yourself with a pair of strong mole grips and a large screwdriver?

JohnRogers
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Post by JohnRogers » Mon Dec 14, 2015 3:12 pm

Sorry to say that I wilted while attempting this. I guess you are advising that all it takes is brute force.

Pod
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Post by Pod » Mon Dec 14, 2015 3:48 pm

JohnRogers wrote:Sorry to say that I wilted while attempting this. I guess you are advising that all it takes is brute force.
Well, yes - and more than a little care as I'm sure it would be easy to break a finger!

Still, I'm sure your local garage could do it, rather than having to do a 100 mile round trip.

Alternatively, leave it until you next meet up with E24 owners, where I'm sure someone will be very happy to help you out, as you don't really need it connected to use the car, which is most likely parked up for the winter now :wink:

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wattsmonkey
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Post by wattsmonkey » Mon Dec 14, 2015 4:57 pm

John,

If the garage disconnect the driver's side, or "other end" of the bar which has come adrift (very easy as it's not under tension at the moment) it's then easy to push the loop as pictured back into its locating slot on the passenger side. Brute force is then applied to re-connect the "other end" back into its place on the driver's side.

Trying to force the loop back into place under tension can lead to injury, lack of success and lengthy bad moods!

Your hinge mechanism doesn't look bent out of shape, but a cable tie as per the posts you've mentioned will prevent future "over-centre" fun.

Rob
"Most of it necessary; all of it enjoyable[!]" LJKS
'86 M635CSi #367 Bring the Noise.
'84 635CSi, dogleg fun

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Brucey
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Post by Brucey » Mon Dec 14, 2015 5:10 pm

hi John,
putting the spring back is only half the battle; I'm not sure I'd bother to re-engage the spring without taking some other form of remedial action as well.

I can see from your picture that the mechanism is worn (mainly because it has been entirely grease-free for some time from the look of it), and if you fit the spring back as it was, the first time the boot opens fully, the mechanism is going to go overcentre again and the spring will pop out.

So.... I think you need to either fit something to limit the travel of the boot hinge or you need to fit something to limit the travel of the spring loop itself.

sorry I couldn't come yesterday, it would have been good to catch up

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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sansouci
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Post by sansouci » Mon Dec 14, 2015 6:43 pm

Would it take less brute force to work inside a closed truck with a hook tool or vicegrips and a flashlight?
Bring a hammer to tap it into position. Grease is always good!
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Da_Hose
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Post by Da_Hose » Mon Dec 14, 2015 7:23 pm

Closed, the boot lid puts the spring under maximum compression. Work with it open. A trick I have learned is to tie a piece of wire or super strong zip tie around the end of things I need to pull and then use a wrench as my handle. Once it is all locked in, I can cut off the loop and remove the wire/zip tie.

Jose
1987 M6 - My dream car

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sansouci
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Post by sansouci » Mon Dec 14, 2015 8:51 pm

My brain was working backwards on this one.
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84 E24 633Csi Auto, Bronzit/PearlBeige 6997510
93 E32 740il M60 Auto, Alpenweis/Ultramarine
60 528i M30 5-speed Green/Beige (crushed)
71 240Z 4-speed White/Blue (rusty & sold)
65 396 Chevelle 4-speed, Marina Blue/Black (stolen)

JohnRogers
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Post by JohnRogers » Mon Dec 14, 2015 10:46 pm

Brucey, I now understand better the comment Chris has in his 2006 posting. He talks about fixing a golf tee. Presumably this was his solution to reducing the travel of the boot hinge - which you suggest. Clearly this is quite an easy modification - once the loop has been correctly positioned.

Many thanks everybody for great advice.

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Post by brtele » Thu Dec 17, 2015 4:33 pm

I did the golf tee fix a few weeks ago and it seems to have worked great. The best was my Wife held the trunk open while I installed the tee and asked alarmingly if I fixed everything like this.

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Post by bpoliakoff » Thu Dec 17, 2015 11:43 pm

I bought one of Brucey’s wonder tools for setting the torsion springs in the trunk(boot) Although a simple device it was well worth the $50 I paid him shipped to the US
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.

JohnRogers
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Post by JohnRogers » Fri Dec 18, 2015 10:21 am

So Brucey, do you still have a tool available for purchase?
Regards, John Rogers

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Brucey
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Post by Brucey » Fri Dec 18, 2015 8:11 pm

yes John,
if you want one just let me know.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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wattsmonkey
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Post by wattsmonkey » Sat Dec 19, 2015 9:33 am

Hey Brucey,

I'm intrigued! The pictures aren't working in the link for me, any chance you could stick one on here?

What about a sticky on the For Sale forum for stuff like this? Maybe including your AFM fixing / strut rebuilding service? I dare say there are quite a few people who might browse the "for sale" section (like I do with Retro Rides and Forum5) who might miss this

Cheers,

Rob
"Most of it necessary; all of it enjoyable[!]" LJKS
'86 M635CSi #367 Bring the Noise.
'84 635CSi, dogleg fun

JohnRogers
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Re: Boot Trunk Mechanism

Post by JohnRogers » Thu Jan 07, 2016 5:24 pm

Brucey, a chaser to remind that I would love to buy one of your boot tools. Please let me know. Regards, John Rogers

JohnRogers
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Re: Boot Trunk Mechanism

Post by JohnRogers » Sun Jan 31, 2016 3:37 pm

Greast news. Got my boot / trunk fixed.

Took my M6 to my local walking distance garage - Leinster Motors http://www.leinstermotors.co.uk/. Charming owner, quite an ordinary sub-urban location but they do much work for local dealers "Classic Chrome" http://www.classic-chrome.net/ I gather they have seen a variety of BMW cars with similar boot / trunk mechanism problems. Probably most of their customers do not regard these as Modern Classic Cars. They took 0.6 hours. Their hourly rate is £81.60 vat inc.

As advised by Chris Wright in his 2006 posting at viewtopic.php?t=3367&highlight=
I have now added some padding. My golf tees would not fit so I have used some thin wooden rod. Note the heavy scratches on the linkages. Looks like they had an excellent battle.

And I have added some grease to the vital parts.

Many thanks to every body for advice. Regards, John Rogers
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Brucey
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Re: Boot Trunk Mechanism

Post by Brucey » Tue Feb 02, 2016 10:00 am

JohnRogers wrote:Brucey, a chaser to remind that I would love to buy one of your boot tools. Please let me know. Regards, John Rogers
Hi John,
for some reason I missed this; whilst I haven't been up to much anyway, having seen what they have done to your boot hinges I feel somewhat guilty. If I had been able to supply you the correct tool your paintwork would have survived unscathed.

BTW the spacer-fix is OK but it leaves the full load of the springs passing through the pivots at all times. The peak load on the pivots occurs when the boot is fully open and this is when most of the wear occurs; if the boot is left open and flaps about in the breeze then the pivots can be wearing quite quickly. When the pivots wear a bit more the mechanism can go overcentre again.

The alternative approach is to fit a stopper on the mechanism, so that the springs are stopped directly just before the boot is fully open. This means that the boot lid is free-er to move about in the breeze when it is open, but the pivots no longer see the full spring load, and wear is reduced. Crucially, the stopper also means that it doesn't matter how worn the linkage pivots get, the mechanism can never be forced overcentre.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

JohnRogers
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Re: Boot Trunk Mechanism

Post by JohnRogers » Wed Mar 23, 2016 6:14 pm

I was able to look closely at Brucey’s Boot / Trunk spring set up while at Mercedes Benz World on 20th March 2016. Brucey then looked at my set up and provided clear further guidance.
Below are images of Brucey’s set up. His red interior makes for better images than my black paint. Overall it shows correct settings for right side and left side. The detail (slightly out of focus) shows detail of Brucey’s Right Side add on to provide a secure stop.
Here is a repeat of Brucey’s text…………fit a stopper on the mechanism so that the springs are stopped directly just before the boot is fully open. This means that the boot lid is free-er to move about in the breeze when it is open, but the pivots no longer see the full spring load, and wear is reduced. Crucially, the stopper also means that it doesn't matter how worn the linkage pivots get, the mechanism can never be forced overcentre.
Brucey commented that my right side springs have not been engaged by my garage. I await Brucey’s tool to remedy this. Brucey also explained that there are two slots for the springs to engage. The rearmost of these is the stronger position. He confirmed that my spacer fix (as advised on Big Coupe) is a less secure solution.
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Right Side 25.jpg
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Detail RS Stopper 33.jpg
Detail RS Stopper 33.jpg (79.34 KiB) Viewed 2453 times

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