Cab top almost closes, but not quite

[tadink]

Hi all -

The car is a 76 911s coupe converted to a cabriolet, with the 2-part top, rear window zips open, I'm suspecting that was from the '83+ vintage?

The issue is that the top *almost* reaches the front window frame, and when 2 big guys 'urge' it closed, the closing mechanism works and it locks down fine. Without 2 big guys helping, and helping pretty hard, the locking mechanism misses the locking channels in the window frame, and the top does not lock down.

Question - are there adjustment screws or mechanisms that might make this process a bit easier? The top is manual-only for raising and lowering (ie the motors have not been installed) but the locking mechanism is intact and operational, the micro-switches are present and the motors work fine.....

Do we think the top has shrunk? Would a new / old replacement top be any better than what I've got?? My rear window is a bit crusty, not too bad and the top is in otherwise great condition!!

I hate being the guy with the top down in the rain as we were last week in Beverly Hills - looks pretty silly sitting in traffic with a towel over my wife! I thought it never rains in SoCal!?!?

Back in Napa now - raining like crazy (yay!) and would like to venture out at some point with the top in the UP position!!

all help appreciated -

td

[cabmandone]

Toward the front of the top there should be tension springs. You can access them by removing the seal that screws to the top. You might have to make some adjustment at the back to allow the top to come forward more also. I think there are adjusting bolts in the back seat area. Have you tried unzipping the back window and latching? There is some adjustment in the rear bow that would allow it to come forward slightly if the top will latch with the back window unzipped.

The more I think about it, it's probably your tension cables that run from the front to the back of the top. There is the spring I mentioned that can be adjusted to add or relieve tension on the wire. Again, just access it by taking the horizontal seal that the door glass seals to on the top (hope that makes sense) and you'll see a pocket at the front of the top frame where the spring is located.

[tadink]

Oh man -

would'nt it be great if it were that easy?!?! I'll go have a look and report back -

thanks Cabmando for the response!!
td

[Dr J]

Before you adjust anything try this:

1. Unzip the rear window
2. Close and lock the top- should be easy now
3. Re zip the window

[tadink]

Dr J -

still does not reach with the rear window zipped out - short by about an inch....

I've got the tension cables exposed, but don't really see that adjusting them will give me the room I need - about an inch. I would think if it was just the spring on the cables I could pull the thing forward under tension? it is really an effort to get it closed, feels like more than just a spring cable adjustment but I'll give it a try -

I'm looking at the cable connections.....their adjustment does not seem obvious....

thanks guys

[cabmandone]

Originally Posted by tadink

Dr J -

still does not reach with the rear window zipped out - short by about an inch....

I've got the tension cables exposed, but don't really see that adjusting them will give me the room I need - about an inch. I would think if it was just the spring on the cables I could pull the thing forward under tension? it is really an effort to get it closed, feels like more than just a spring cable adjustment but I'll give it a try -

I'm looking at the cable connections.....their adjustment does not seem obvious....

thanks guys

The adjustment wasn't obvious to me at first but if you look, there are "dimples" on the piece that bolts to the frame, when the bolt is tightened the spring can't slip past that dimple which is what keeps tension. You can also check your arms in the back seat. There will be a retaining nut under the rubber piece on the arm. I think if you make the arm longer it throws the top forward, shorter brings it back. I'm not 100% sure on that part but I believe that's how they work.

Are you saying your alignment pins are 1" away from the windshield? That's one hell of a lot!

[tadink]

--sob--I'm a failure!

I took the adjustment clips completely OFF the springs, still would not close!!

yah, I can barely get the pins into the holes on the windscreen, and then when pushing down HARD I'm still about 1/4" shy of the cams engaging into the channels for the top close mechanism.....

ugh - well at least I did no harm and got it all back to where it was....man, I don't see ANY other place to adjust this thing!

what's next????

td

[Dr J]

TD did it ever close before? Does the skin of the roof look very tight? The only other suggestion I can come up with is to wet the top well, unzip the window and try it. If that doesn't work what I would do is start disassembling the canvas at the front of the roof. Hopefully someone else has a better solution.

[cabmandone]

You could go to Harbor Freight and buy a portable steamer and steam the top to stretch it. IF the top was down for a long period of time you might need to stretch it back to get it to close. I've heard they will shrink up if the are left down for extended periods of time. I know when my new top was installed they had to steam it to get it to close. Might be worth a try.

[tadink]

Originally Posted by cabmando

You could go to Harbor Freight and buy a portable steamer and steam the top to stretch it. IF the top was down for a long period of time you might need to stretch it back to get it to close. I've heard they will shrink up if the are left down for extended periods of time. I know when my new top was installed they had to steam it to get it to close. Might be worth a try.

The top has been down a long time before I bought the car - and I've had it closed twice since I've owned it.....so it does close, but it is hard to get into the right geometry to get the cams to engage....

The steam trick sounds interesting - and it is going to be warm here this week so maybe soaking up the sunshine for awhile will help as well....particularly if I soak the roof pretty well prior to the sun-bath.....

I'll update along the way -

thanks for the ideas! TD

[Dan J]

lengthen the strut arm on each side It's the funky looking one

[tadink]

Originally Posted by Dan J

lengthen the strut arm on each side It's the funky looking one

uh, how does one go about doing that? I don't see an adjustment mechanism - are you saying have one fabricated?

[Dan J]

Should be an adjustment where it attaches to the body

[Dan J]

Should be an adjustment where it attaches to the body

[cabmandone]

See the black arm that extends out of the cover where the speaker mounts? There's a nut to lengthen that arm. If I take the cover off there's an adjusting bolt there too I think. Maybe take a picture of your mechanism in the back seat and post and I'll post a pic of the one in my 85 and we can compare and go from there.

[tadink]

My top mechanism terminates at this bracket on the car, where the shiny nylock nuts are located. I'm hesitant to remove those nuts since I don't know what's back there and they will be impossible to get back on if the bolts need to be accessed to stop them turning as well, the seat belt retraction mech is completely in the way!!

The support bar for the top slides up and down in a slot, and even when I lever the mechanism all the way to the up position of its current setting on both sides, I'm not getting close enough to close the top. Does the bracket that is held in place by the nylock nuts have vertical adjustment? ie, if I loosen the nylock nuts, will I be able to move the bracket UP?

[cabmandone]

It's dinnertime! I'll go out after I eat and take a pic of my car. But from memory, that looks nothing like what I have.
Before I eat, no matter how well it's adjusted, the latch mechanism are hard to close. So if you're having a hard time latching, that's not uncommon.

[tadink]

Originally Posted by cabmando

It's dinnertime! I'll go out after I eat and take a pic of my car. But from memory, that looks nothing like what I have.
Before I eat, no matter how well it's adjusted, the latch mechanism are hard to close. So if you're having a hard time latching, that's not uncommon.

uh oh - I was worried about that! I hope that whomever did my cab conversion did not just get creative with the mechanism....

'hard to close' I can deal with - virtually 'impossible to close' is where I'm at now.

working on an idea with a block and tackle to pull the thing forward enough to get the cams into the channels - I'm struggling with leverage!! but don't want to break anything in the process!!!

[cabmandone]

On the bottom of the arm with the nylon nut there is a jamb nut that you can adjust. There are also threads on the top that can adjust the throw of that arm. In order to adjust, you have to remove the bolt with the allen head from the top and then turn the arm to lengthen it. You'll want to make sure you have both the passenger and driver side measuring the same so you don't put the top in a bind. I think that should help move the top forward. Someone else might chime in if I'm wrong. Look at the pics I attached an see if it makes any sense to you.

[cabmandone]

BTW, I wouldn't get too aggressive with pulling. If anything you could try removing the allen head bolt that attaches the arm to the bolt with the nylon lock nut and then try pulling the top forward to latch and then adjusting the length of the arm once to top is closed.

If you adjust by lengthening the arm, I'd count the number of turns you make just in case this adjustment doesn't work. That way you can reverse whatever you do.