Dropping off the pace car for a new convertible top tomorrow. Anything in advance I should keep an eye out for or mention? Shop is quite reputable and does very nice work.

I have new rubber seals all around, black vinyl for the header area, and I know they're going to need to reconfigure the side glass as the two chrome strips on each side need to be installed, etc. Any lessons learned from those out there that have had top work completed?

The frame has been "restored" but a previous owner left the top down for 5+ years and the material didn't hold up. I installed new cylinders and pump a few years back.

 

What brand top are they installing? Electron was the best for a long time but they sold out to another company and word is quality is no longer there.

1) Make sure all of your top frame adjustments/alignment is done BEFORE the top goes on.
2) Check the cables being installed. For sure, they'll install new cables but these sometimes have a tendency to break. Even if they're newer. Give them the once over to make sure quality is good.
3) Highly recommended to align all four windows prior to installation. This is related to #1.
4) I was told long ago the original factory design of the '68-'72 A-body tops had a design flaw where the material is tacked to the large hoop bow at the rear (above the rear seat). Original tops had the 'cover piece' (not sure what it's technically called) drape over that hoop too far and, over time, it caused the material to tear. This is the point where the small, stainless end pieces are screwed in. Most installers now recommend keeping the length of that cover piece 'shorter'. This means it doesn't drape over the curved contour of the hoop as far as the original installation. It supposedly reduces the stress on the material at that point and minimizes future tears. I did mine that way and most of the cars I've seen since I've noticed are done that way.

Good luck!

 

Good pointers, thanks. The top is from Robbins, I believe. The side glass is the biggest concern as it's a mess in terms of alignment. Hoping they're able to get it dialed in.

The installer suggested new cables so we're doing that as well.

Hoping the new chrome side glass trim with the rubber from Fusick fits well. I believe in the package it also came with the tape for the edge of the glass as the trim appears to be compression fit.

 

Somewhere around here I have a thread on adjusting tops before going after roofrail rubber.

The upshot is you want to get the top frame aligned pretty tightly to the tops of the 4 windows and their upper inside edges to make for a quiet top. If it were me, I’d get the top frame right on top with as little gap between the windows and frame as possible - even before the roof rail. I’d aim at having the roof rail press down on the glass by just a little to form a tight seal.

I didn’t remove my fabric, but have adjusted the rear hinges to get closer to this goal.

As you chase this stuff realize you might wind up fiddling with door hinges being worn and door alignment too in pursuit of getting it right.

The sealing system is a combination of top frame, roofrails, door alignment and sound hinges.

Convertibles are harder than hardtops because they bend which creates a kind of moving target for sealing surfaces.

Hope that helps. Wishing you every kind of good luck with this project.

Chris

 

You're 100% spot on. I hadn't thought about the door hinges being a part of it but that sounds right. Let's see how good the shop can get it...

 

My main advice would be: if you're not satisfied with the fit when you go to pick it up, get them to do refit or adjustment before you pay. Often these places will tell you things like, "Oh, those wrinkles will come out if you just leave it in the sun for a few hours" just to get you to give them your money and go away. Trust me, if it's wrinkly after installation, it's going to stay wrinkly until properly fitted.

 

For the hinges, if they’re are sound and not sagging, your door will have consistent gaps along the rear vertical edges of the doors and the lower gaps between the bottom of the doors and the frame. If the gaps narrow at the lower rear corner, you have to decide how far you want to go correcting it, or deciding you’ll move the top & windows to make up for any sagging.

Another way to tell if the doors are right is to simply open them. If you see the door drop within an inch or 3 of coming off the latch bolt, you have some choices to make.

As designed, your convertible frame bends just a little, when you go over bumps. Luckily the window regulators and top frame have enough looseness so that if you get it right on flat ground, you’ll be fine. Remember the slip joint on your driveshaft? Yup that’s why it’s allowed to slip…

I have a couple of gap measuring tools which are no more than a couple of 3-4’ strips of 3/16” thick plastic and 1/4” thick plastic . They look kind of like sticks, but the thickness and bendy-ness of the plastic is what tells you if your gaps are correct and consistent over the lengths & height of the doors. Plastic doesn’t mar paint finishes, but you could also use something like 3/16” and 1/4” aluminum strips to read the gaps. You just slip the stick in the gaps and see what you learn. Not hard, but hope it’s worth mentioning.

In 3rd place, don’t worry so much about the front fender gaps since the fenders are highly align-able (aka, they can be moved after the doors are correct).

Mainly I’d say don’t start chasing the top until you know the doors are right. Or your shop will fit the top to your, possibly incorrect, doors.

The window part of this is important too. If they’re not right, and since their position is based on the doors, they will have to adjusted to fit the top. Then you’ll find yourself in compromise land trying to get them best (quietest, water-tightest) fit you can knowing some parts of the system are off. I hate leaky whistling windows. Hate. Like days worth of work trying to fix hate.

I’ve come to the conclusion that windows take so much time to align that it may not be profitable for a shop to even begin those projects unless they know the make/model/year very well. The customer charges would be very high, so they may take the route of just fitting the top to the existing windows to stay out of the window-alignment time suck mess. But if you get a whistling, not water sealed car back, you might not be real happy about that.

Sorry if I’ve gone on too long. If you’re interested look around under my user name for my adventures (and continuing adventures) in the space of making these old cars quiet. It’s harder than you’d think…

Cheers
Chris

 

Shop called me today and asked me to stop by. When the top is operating, there appears to be a "popping" sound with the frame and then it starts to move. He showed me the hardware on the frame is Home Depot junk. I went ahead and ordered a bolt / pivot kit from the Parts Place. Not sure how correct TPP hardware will be but it'll certainly be better than what is in there now and it's close enough to pick up. Anyone use their kit?

https://www.thepartsplaceinc.com/pro...bushings/51696

 

 

I found similar hardware store hardware on mine back in 1990 when I replaced the top. It’s amazing to me that someone could “lose” those unique fasteners, but then I am the guy that keeps every original part that was replaced in a box that will live with the car on its journey through time. Back then my only choice was to make my own fasteners on a lathe (those 4 bolts in the center of your linked image; but I recall making only 2?), so it’s good to see they are available these days. I also bought the nylon bushing/washers that go on the ends of the hydraulic cylinders from an industrial hardware outlet and had to cut the bushing section down to the correct length.

 

In case it helps, you can get good hardware which is not exactly factory standard.

The outer diameter of those bolts and related nut thread aren’t exotic. It’s mostly a matter of finding hardware that will be easy on whatever fabric or parts rub against it. More or less this means hemispherical (rounded off) bolt heads and nuts.

On my ‘66 98 convertible, it always had acorn nuts on the inside of the cabin (i.e. the factory bolts were fed in from the exterior facing direction - inward). But perhaps they were wrongly reinstalled in reverse & the hemispherical acorn nuts should have been on the outside so that the rounded hemispheres didn’t tear the top fabric.

Anyway I always thought acorn nuts were a good solution to secure the lifting mechanism and have a safe surface for the top fabric to ride against here & there. Their rounded nature seemed to be a good way to _not_ wear through convertible top fabric.

As I recall my original factory bolts were chrome plated bolts with rounded edges that also had a hemispherical shape. You can guess I liked these too on the idea that rounded bolt heads would hurt fabric less than standard hex bolt heads. But if you can’t find those these days, I’d put the acorn nuts on the exterior side of the top-raising bolts and go with hex-head or (like I did) use Allen wrench nuts to screw into the acorn nuts on the outside.

I’ve never needed to shim the outer diameter of my bolts with teflon or any kind of gasket since the hydraulic systems are so strong. Just acorn nuts, bolts and maybe if you’re into it, a teflon washer or 2 on each end, just to encourage smooth top movement.

The washers I’m referring to here would go on the inside and/or outside of the black top hinges to create a flat consistent surface (that resists wobbling) to ride up and down against. More or less you’re putting in some smooth riding surfaces which should encourage smooth (up/down) top operation and limit/resist side to side loose hardware slop.

I’m not an A-body guy, but these tips & tricks worked for my ‘66 98 top which is mechanically pretty close to your Cutlass/442. I hate mechanical slop from 50+ years of wear and love tops that go up and down smoothly. Since we big car guys have to get creative, maybe this helps you.

Cheers
Chris

 

The load bearing stresses on the top frame are miniscule so the cheapest hardware that'll fit would almost certainly get the job done. That is, unless (God forbid) you were in an accident or rollover. I don't think the factory hardware would do much to save your a$$ but it was/is much better than today's imported hardware store junk.
Luckily, my top has its original hardware and if it did need anything, I would have sourced used originals.
Looks like whoever put the last top on that pace car really took some 'creative liberties'.