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Discussion Starter #1 (Edited)
Unfortunately the latches that secure the soft top to the windshield eventually fail. This DIY will cover:
- Why the latches fail
- How to determine if the latches are failing
- How to remove the latches
- How to strengthen/repair the latches

Background

There are actually 2 sets of latches that secure the soft top to the windshield:
  • There are the 2 obvious latches that clamp to the windshield; and
  • There are 2 "elbow" latches that pull the soft top tight to the windshield.
This is the elusive "elbow latch":


Both these latches are controlled by 2 latching mechanisms hidden under the metal cover at the front of the softtop. The latches are mirror images of each other so lets look at how one works and why it fails.



A motor turns the threaded rod which moves a composite part (orange) back/forth. As it moves it pushes a metal bar in/out (red) that controls the "elbow latch", and a metal bar up/down (green) that controls the windshield latch. The up/down motion must exert too much pressure on the composite part as it eventually cracks around the metal bar. This is my latch starting to crack:



If left the metal bar would eventually break free of the composite part, rendering the windshield latch inoperable.
  • If the part breaks while the roof is opening you better hope for good weather, as the soft top will be unable to latch to the windshield.
  • If the part breaks while the roof is closing you have 2 options:
    1. Cut the cover with a reciprocating saw to gain access to the latches. The cover hiding the latches isMETAL.
    2. Remove all the interior trim around the windshield near the latches, then the bolts can be accessed to remove the cover. There is no DIY for this at this time. A single member has mentioned they were able to do this successfully.
Options to repair the latches:
1. Reinforce to prevent failures. See the DIY below.
2. Repair kits are available. Unfortunately the repair kits have been found to have incorrect threading or be of low quality. Incorrect threading can cause strain on the system causing other parts to fail.

How to determine if the latches are failing

There is a way to check if the composite part is beginning to fail. Manipulate the top (electronically or manually) into this position.

]

NOTE: Do NOT rest the storage compartment lid on the soft top. Get a friend to help.

Compress a windshield latch by hand (they are spring loaded).



Then look in the triangular opening to find the composite part. A flash light or good lighting is a must. In this photo you can see a crack in the bottom corner. Both my latches had cracks in the same place.



NOTE: The photo was taken post strengthening. Your part will not have the bolt and washer installed... yet!
 

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Discussion Starter #2 (Edited)
How to remove latches

Required:
T10, T20, and T30 torx bits or screw drivers (or get a whole set of torx bits! you own a German car, you're going to need them!)
Phillips screw driver
Flat screw driver
Pliers
Bright flash light
7mm socket

Step 1: Manipulate the top (electronically or manually) into this position.



NOTE: Do NOT rest the storage compartment lid on the soft top. Get a friend to help.

Step 2: Remove the 9 T10 torx screws along the leading edge of the top.

Step 3: Pull out the weather stripping. Mine was attached with silicone (another DIY recommends this to fix leaky tops) so be careful, this part is not cheap.



Step 4: Remove the plastic caps that cover nuts at the corners of the leading edge of the top.



Step 5: Remove the 7mm nuts, and the hidden T20 screws.



Step 6a: Remove the 2 Phillips screws holding the corners of the headliner.



Step 6b: Pull the cover off. If it won't pull off easily, move onto the next step. My cover was glued on (my car has had 3 soft top repairs due to vandalism).

Step 7: Detach the headliner from the cover. There are 6 T20 screws. Try loosening all 6 screws first and pull the cover. If that doesn't work then loosen the outside screws, remove the inner 4, then lift the metal bar out. The outside screws attach to plastic guides that help install the metal bar that holds up the headliner. Pull the cover off.



Step 8: Disconnect the latch electrical connector (black, not blue).

RL]

Step 9: Disconnect the motorized rod. Use a flat screw driver to pry it off.



Step 10: Disconnect the elbow latch. Turn the threaded rod until the elbow latch moves into this position. Remove the c-clip and pull the metal rod off.



Step 11: Remove the 4 T30 torx screws that secure the latch.

The latch is free!

Note: To reinstall just reverse the steps.
Note: Ensure the threaded rod is turned such that both sides have the latches in the exact same position. This ensures they clamp at the same time with the same force. The position doesn't matter since the CVM can figure out what position the latches are in an compensate.
 

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Discussion Starter #3 (Edited)
How to strengthen the latches

Required:
- 4x M5 25mm bolts
- 8x 5mm washers
- 4x M5 lock nuts (or regular nuts with a lot of loctite!)
- Loctite
- Plastic Weld putty http://www.jbweld.com/product/j-b-plasticweld-putty/
- Super glue (if there are any cracks)
- Sand paper (150 grit or rougher)
- 8mm socket
- needle nose pliers (or vise grips)
- drill and bits

Optional
- Lithium grease (general purpose and/or spray)

Step 1: Turn the threaded rod by hand to move the latch as far out as possible. It should turn easily.



Step 2: Super glue any cracks.

Step 3: Drill 2 holes for the M55 bolts. Drill a pilot hole with a small drill bit, then drill bigger holes until the M5 bolt fits. Use the following as a guide where to drill.



You'll notice the holes are drilled towards the bottom of the metal bar, and close to the centre of the composite part. The reason is we're aiming for these holes in the metal bar.



Step 4: Secure the M5 bolts with M5 lock nuts. Use the pliers to position and hold the lock nut as you won't be able to get a wrench into the space. Use Loctite too if you're paranoid like me.

Note: A 25 mm is slightly too long, so use 2 (TWO) washers on the head to prevent damaging the composite part as it is tightened. A 20mm bolt is too short.



Step 5: Prep the composite part for the plastic putty by lightly sanding the surface. Don't forget to do this! (I did and had to redo the next step).

Step 6: Kneed the putty as per the directions, then squish around the lock nuts and finally build up the top of the composite part. The goal is to make the part as strong as possible.

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The result should look like this:



Step 7: Turn the threaded rod by hand to move the latch back to where it started. It should turn easily.

Note: It is not important to get the position exact.
Note: It is important to set both latches to the same position.

Optional

Step 8: Lube all moving parts with lithium grease. I used general purpose grease on the threaded rod and metal slot, and sprayed lithium grease on all the pivot points.
 

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Thanks very much for this write up.
I strongly believe I need to do mine as plastic parts are falling out whenever I open the top.
Question, did you have to disconnect the battery before your "Step 8 of removing the latches: disconnect the black electrical connector"?
 

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Discussion Starter #9
Thanks very much for this write up.
I strongly believe I need to do mine as plastic parts are falling out whenever I open the top.
Question, did you have to disconnect the battery before your "Step 8 of removing the latches: disconnect the black electrical connector"?
No need to disconnect the battery... unless you're the type to push buttons, i.e. don't operate the top!
 

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Good write up taylor. I have yet tried to see about getting that part manufactured. I have my old two still sitting in a box. If you catch the damage as you have then this fifx should work. One of mine was broken worse. I think the pictures are up on some thread. I remember we talked about running the bolts through and re-inforcing the plastic part with metal. Looks like you got to yours in time. I'm still going to "one day" get that part machined in aluminum or something.
 

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My left front latch broke and I did this exact fix yesterday. So far; works very well. Here are some additional tips to the already awesome write-up.

1. You don't need to take screws off that connect the headliner to the latch/motor cover but it will take a lot of prying to pull the cover out and it will be hard to impossible to put the cover back without effort. So, loosen those screws but not take out fully as if you do so then it is also hard to align the headliner cloth and screw back in its proper place. These screws are accessible from both sides of the car and they are between the soft top and the interior headliner.


2. A screwdriver is a little hard to use in there, so use a power one that is small and can bend at an angle or even better if you have access to a rachet like this http://www.globalindustrial.com/p/tools/Ratchets-Sockets/Ratchets1/milwaukee-m12-14-ratchet-kit?infoParam.campaignId=T9F&gclid=COiL1u7_tsICFRFhfgodVBIAVA&gclsrc=aw.ds

and Thank you Taylor !

--h.
 

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great writeup.

i'm having issues with reverse step 10. what is the best way to get the rod back down from the top into position. is it really to force it down through the opening?
 

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Discussion Starter #13 (Edited)
great writeup.

i'm having issues with reverse step 10. what is the best way to get the rod back down from the top into position. is it really to force it down through the opening?
Thanks!

You're having trouble getting the rod back to the elbow latch? You shouldn't have to force anything. Twist/turn till the rod slides through the opening into position. I do remember it wasn't a straight forward fit due to the bends.

Netflix has all the MacGyver episodes, watch some for inspiration. :excited:
 

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Just did this repair yesterday and these instructions were very helpful. To anyone else about to do this I would add that you should pay attention to how the weather stripping tucks into the cover at the corners of the roof. There is a section of the cover that comes to a point on two ends. The weather strip has a cutout that fits over this. Make sure you tuck this back into place or I could see how water could leak in at the corners.
 

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That rubber seal is now about a $400/500 price tag So be extremely careful when taking this off. The corners tear very easy when trying to put the cover back on the rubber. The first time I tried this, mine tore a little and I was able to put a little super glue on the rip and it worked good but would leak some during heavy rain.

When I re-did my wire harness I figured I would replace it and good thing I budgeted for it because it totally ripped when I took it apart a second time.

Fortunately for me, I found a parts supplier that was asleep at the wheel and never adjusted their price so I got it for $270. Still a lot of money. After I bought it they later changed the price to match what every one on the Internet was selling it for $380 +-.

The easiest way is to remove the rubber with the cover. To do that you have to remove two screws (each side) to the trim over the front windows. Fold the trim back at the split and you will find two screws in there. The rubber trim runs along the front windshield and then over the front windows. It is all one piece.

Once you get those four screws out you can pull down the cover with the rubber still attached to it.

This will work best if you had a person on each side of the car holding up the part and you remove it so it is not dangling bit if done slowly one guy can do it.

That is my word of advise. Save yourself the $400 by adding about an extra five minutes to the job.
 

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Hello Mates,
I am new to this forum, this thread is what brought me here. My windshield latches cracked when I let my brother borrow my 330CI and he tried opening the top while the car was in motion :evil::evil: so I googled and googled until I found this thread, I just completed the repair that was shown here with the screws, bolts, and jb weld clay to try to get it to work again. The plastics on the latches were cracked in half :(:( But I hope this DIY repair works, I will wait until the end of the day tomorrow to try it out.


But my main concern is that I messed around with the shocks that are connected to the latch, before I know the plastic on the latch was cracked i thought maybe the shocks went out so I unscrewed them and try to make them more up, ok my question is how far apart from the nut is the shock supposed to be ?

Pictures would help a lot please !! I would hate to try to put my top up and then since the shocks are tied close the plastic latch will crack again.
 

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Discussion Starter #20
There is a large 50A fuse in the glove box that cuts all power to the top.

You'll have to post a photo of the "shocks", I don't understand what you are talking about.

ECS tuning sells the latches, and the listing has lots of photos that may help.
 
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