Seeking advice on problem with convertible top.

[tsklan]

Hello. I recently had my top replaced on my 98 M Roadster. It's a Gahh top and the installer has been in the upholstery business for a long time. He told me that he had installed several Z3 tops.

My problem is that the new top does not completely clear the roll-bars. When the top is shut and latched down, the roll-bars push against the back of the top.

The original top had 0.5" or so of clearance. The top never touched the roll-bars at any point. I looked at another Z3 M and that top wasn't touching either.

The installer agreed, rudely, to take another look, but I have a feeling he isn't going to help unless I spend my own time figuring out what is wrong. He seems to think it's impossible to remedy the situation and that I shouldn't worry about it anyway. I disagree. The appeal of the car to me is the way it looks and the resulting bumps on the back of the top look bad to me. Also, I imagine that the top will wear prematurely at these points. I don't have much recourse with the installer since I paid for this work months ago. I was working out of state when he finished.

So, could other M Roadster owners confirm that their tops don't touch the roll bars? Has anyone heard of replacement tops rubbing against the roll-bars?

Thanks

[BUCK57]

I never saw this on my 98 or 01 M. Both tops were/are OE tops. I never had any bump, bulge or sags with factory tops. The new glass looks nice.

As far as the fix, a proper fit/adjusment and I have no expericence other than MG/Trimph tops that were a ............................ The Z3 top is so nice!!

[tsklan]

Thank you. I imagine driving top-down is a lot of fun in Long Beach.

[nahvkolaj]

I did the top myself on my ‘01 3.0...twice, because the first one had a failure. Two things caught my eye.

1. In the second pic the webbing is not taught. That webbing offers support to the canvas and makes sure the support bows line up where they are supposed to. If it’s not taught when the top is closed, something is wrong.

2. (and maybe caused by point #1) It looks like aft-most support bow is not being positioned correctly. That seam should be right on top of the support bow. I believe that is why you are seeing the roll bars hitting the canvas.

[Vinci]

The top itself has no bearing on the issue. The frame controls where the canvas sits.

The installer didn't get bow #4 in the correct position during the install. That should be below the seam. Yours looks like it is in front of the seam, which means the bow isn't all the way back, which will allow the canvas to contact the roll bars.

See the photo in step #22 of my install guide to see where it ought to be. The solution may be as simple as opening the top (to take tension off the canvas) and moving that seam on top of bow #4. When the top is new, the canvas is tight. Moving this may make it tighter. The installer may have left the box out of position to make the top easier to close (bad), instead of doing the right thing and stretching it closed so it can get into shape. Read that section of my guide for move info.

[tsklan]

Thanks, that helps a lot.

[tsklan]

I very much appreciate the information, Vinci. Great guide. I wish I had seen it before.

[JustinHalverson]

The top itself has no bearing on the issue. The frame controls where the canvas sits.

The installer didn't get bow #4 in the correct position during the install. That should be below the seam. Yours looks like it is in front of the seam, which means the bow isn't all the way back, which will allow the canvas to contact the roll bars.

See the photo in step #22 of my install guide to see where it ought to be. The solution may be as simple as opening the top (to take tension off the canvas) and moving that seam on top of bow #4. When the top is new, the canvas is tight. Moving this may make it tighter. The installer may have left the box out of position to make the top easier to close (bad), instead of doing the right thing and stretching it closed so it can get into shape. Read that section of my guide for move info.

I just completed an install of a new top. Bow #4 on my installation is about the same place as that shown by tsklan. However, I have not interference with the roll bars. I didn't think it looked quite right, but wasn't unhappy with it. Looking at it, it appears the position of the bow is established by the four straps attached to bow #4. The straps that go down from the bow to the sealing frame are the ones that pull the bow back. The OP's pictures show that the straps going forward are loose. If anything that should allow the bow to go further back.

Am I missing something?

[Vinci]

I just completed an install of a new top. Bow #4 on my installation is about the same place as that shown by tsklan. However, I have not interference with the roll bars. I didn't think it looked quite right, but wasn't unhappy with it. Looking at it, it appears the position of the bow is established by the four straps attached to bow #4. The straps that go down from the bow to the sealing frame are the ones that pull the bow back. The OP's pictures show that the straps going forward are loose. If anything that should allow the bow to go further back.

Am I missing something?

When the seam is positioned behind bow #4, it is in a lower-tension state. It has not been stretched into its proper position. As a result, it holds bow #4 in front of itself when the top comes up, which results in the straps forward of it being slack, since bow #4 is further forward than it should be, relative to bow #3.

When the canvas is new, it needs to be stretched into its proper position. This is how the top avoids being floppy. There can also be variables in the installation, since this is a non-OE top. Assuming all other installation work was good, the bow being out of position is what is causing the canvas to contact the roll hoops. If there are other errors in the install, then something else can be causing bow #4 to be out of position.

[tsklan]

The installer texted this morning saying that he "moved seam forward rear bow" and my car is ready to pick up. I hope this means he was able to fix it as you described to me, Vinci.

Assuming the installation problem really is solved, if I discover that the fabric appears to be stretched where it came in contact with the roll bars, would you take the car anyway with the hope that the fabric will smooth back into shape over time?

[Vinci]

The installer texted this morning saying that he "moved seam forward rear bow" and my car is ready to pick up. I hope this means he was able to fix it as you described to me, Vinci.

Assuming the installation problem really is solved, if I discover that the fabric appears to be stretched where it came in contact with the roll bars, would you take the car anyway with the hope that the fabric will smooth back into shape over time?

If you're not going to do the job yourself, you're pretty much guaranteed to have to accept work you're not thrilled with at some point. Your shop can adjust it, and hopefully that takes care of it. You can be pretty certain that they aren't going to go further than that, though.

[tsklan]

If you're not going to do the job yourself, you're pretty much guaranteed to have to accept work you're not thrilled with at some point. Your shop can adjust it, and hopefully that takes care of it. You can be pretty certain that they aren't going to go further than that, though.

You're probably right. I am regularly disappointed in other people's work (not referring to cars, specifically), but it's impossible dto do all jobs oneself. I haven't picked up the car yet, but it seems like if their mistake installing resulted in permanently distorting the top, then the responsibility should be on them. It's probably too late for recourse, though, because I did not see the problem until a couple months after the car was finished (having been out of state). Had I found your install guide earlier, I probably would have done it myself.

Thank you for your help on this. Regards.