Fastback Quarter Windows

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Mister 4x4

Too Big to Sneak
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1971 Mustang Mach 1
OK - I've seen lots of 71-73 fastbacks with 5-position power window switches on the driver door, which I'm thinking are: 1 door lock switch (driver side), 2 door window switches (L & R), and 2 'other' window switches (quarter windows, L & R?). The passenger door has a 2-position switch: 1 door lock and 1 window for the passenger door only.

This leads me to believe that the quarter windows in fastbacks were made to roll up and down, and can have power units as well. Is this true?

If so, I'm thinking I would want to convert my fixed quarter windows to powered units (since I'm going to convert my hand-crank door windows to powered units anyway).

If not - then I guess I'm SOL and no worries.

Anybody?

 
Eric,

You bring up a couple of very interesting questions that caused me to think back to several years ago when I remember having seen a 1971 429SCJ Mach I that had power quarter windows.

In checking some of my research material, I determined that the quarter power windows were in fact available on '71 - '73 Mustangs and that the power window motor used was shared with the '70 - '73 Cougars.

I also determined that several of the "mustang houses" (possibly OMS as well) are carrying the regulators for the quarter windows in '71 - '73 Mustangs.

Based on the above, I would say that the quarter windows are designed to be rolled up and down and that they also were available as power units.

I would think that someone else will chime in with more "hands on" experience.

Hope this helps.

BT

 
YES the fastback and the coupe and the convertible had quarter windows that rolled up and down.

Here is the deal, the coupe and convertible had the option of either manual or power windows as an option.

the Fastback/sportback, only got quarter windows that moved if you got the power windows option there was no manual option on this body style.

to convert quarter windows to roll down is a huge deal, you must find a donor system from a coupe to start finding a fastback with the option is almost impossible.

there used to be a website of a guy that did the conversion from a coupe to a fastback, he never really finished the car though, he couldn't figure out how to make the rear handles function properly, and so he left off the interior quarter panels thinking he would make some custom panels that would finish it off correctly. The site disappeared like 5 years ago

Powered versions of the rear windows will be Very rare, the pancake motors inside are unique and very rare.

the easiest is to take a manual system from a coupe. you may find a system being sold on e-bay it can be over 500$

there are up and down stoppers and a special version of the quarter window seals as well as channel parts and the mechanics that go into the frame. you will not be able to find any reproduction parts, though i have seen some re-manufactured pancake motors around.

the only thing you must change is replacing the coupe quarter window with your fastback quarter window, and reglueing the seals to it. you may have to hack together some proper window Whiskers also since the correct ones are not reproduced.

all the bolt holes and holes and mounts for the window stoppers are already in the frame behind the B pillar so its pretty much a bolt on modification, but you will need to drill out your quarterpanel trim and cobble together a handle to make it look factory, the fastback panels come out further then the coupe and from the factory no fastback mustang had manual rear windows so you will need some talent.

a few years ago i was interested in converting my car to manual crank rear windows, it was more trouble then it was worth to me, so i gave up. Also i didn't want to cut any holes in the ultra rare interior quarter panels.

converting to power windows from a coupe or fastback can be a problem depending on the year of the car and the harness the car came with, otherwise you have to hack things together.


you know i forgot this fact.

on the fastback when you got powered windows the rear windows were unique because they had a half moon cut out of them for the pancake motor clearance.

that was another reason it was cheaper to adapt a coupe manual system and then re-use your fastback windows, but you could only do that with the manual since the glass for power was different.


oh and you would use the coupe system because the upper stoppers on the vert were non-existent due to the roof so it was more complete to get it from a coupe when using it on a fastback.

 
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Interesting topic! I could never figure out why the coupe has roll down quarter windows but the Mach 1 is stationary!

Good info, guys!

 
Wow - talk about quick responses. Thank Guys!

And... aw bummer. I was hoping that it wouldn't be too tough of a deal to make it happen. As it stands, I'm in the perfect position to bolt-on parts and get it done... but if it's going to be that much of a PITA just finding the right parts, then it's just not worth it - I have plenty of other things to do that need more immediate attention.

I was just thinking of how cool it would be to have all of the windows retracted during a nice day like I could do in my old '73 Satellite Sebring way back when.

 
From my experience the half moon cut is in the door glass to clear the power motors.

Never saw a cut quarter window.

There are 3 different quarter window glasses, fastback, coupe and convertible.

Rear glass is the same for fixed or power in the fastbacks and roll up or power in the other models.

Have never seen any different weather-strip or w-strip channels between the power, manual or fixed quarter glass.

Have sold guys several sets to convert fastbacks to roll up rear windows.

Only thing needed to be made is crank handle extensions.

At this time I have 3 -4 set ups for the manual and several complete power set ups.

Don

Ohio Mustang Supply

VISIT US ON THE WEB AT

www.ohiomustang.com

 
Wow! Thanks Don. I'll be talking with you some more after I get my front end and floors squared away (just feelin' the ground on this idea for now).

My interior panels already have some holes cut out of them for 5.5" speakers (which I'll probably just re-use for the same). So a powered set-up would be more along the lines of what I'd be hoping for. And again, I'm not fanatical about complete down-to-the-proper-colored-fasteners for Concours restoration, so coming up with whatever kind of system to make the windows go up and down by pushing a button (and not leak when closed) will work fine for me.

I am SO glad I asked this question. Thanks again, guys!

 
go for the power setup if you do it.. its worth it. they will still leak though :p

 
I've done this modification to my Mach. Installed all the mechanicals from a coupe with the original fastback quarter glass. Bolts right in. Drilled one hole in the interior panel for the crank handle. Looks factory. Very easy to do.

 
I've done this modification to my Mach. Installed all the mechanicals from a coupe with the original fastback quarter glass. Bolts right in. Drilled one hole in the interior panel for the crank handle. Looks factory. Very easy to do.
can you post us a picture of it?

 
Pics? No problem.. Easy bolt in mod. No changes to crank shaft needed.

windowmotor005.jpg


windowmotor004.jpg


windowmotor003.jpg


 
Wow! Thanks Don. I'll be talking with you some more after I get my front end and floors squared away (just feelin' the ground on this idea for now).

My interior panels already have some holes cut out of them for 5.5" speakers (which I'll probably just re-use for the same). So a powered set-up would be more along the lines of what I'd be hoping for. And again, I'm not fanatical about complete down-to-the-proper-colored-fasteners for Concours restoration, so coming up with whatever kind of system to make the windows go up and down by pushing a button (and not leak when closed) will work fine for me.

I am SO glad I asked this question. Thanks again, guys!
Go power windows!!! Really worth it in my opinion. Kinda tricky getting the mechanisms in there but after you do it you have power windows.... yea...:cool:

 
Me? Honestly, I don't care. I'll work on finding an original power kit if possible (Don mentioned having some on-hand). But if I wind up using a manual system with some kind of powered adapter to spin the crank, I'll be happy enough.

I've seen a bunch of "hot rod" kits with compact, high-torque motors that might work. We'll see what happens - but I'm a long way away from worrying about power windows... let alone making the fixed quarter windows go up and down with a button. :D

 
Although I plan to keep mine just the way it is, I thought I should post the two differences that I've found in the control buttons. In my searches, I've found that, once again, the 71-72 are different from the 73s.

Here's a brochure shot of the inside of a 71 with power windows.

Power windows -71brochureinteriorshot.jpg

And here's one that I've found for the 73s.

Power Window - switch driver side.jpg

Hope this helps...

 
1971 to 1973 fastbacks didn't come out with wind down quarter windows - the only way you could go pillarless was to order the electric window option. However all the holes and mounting points are pressed into the inner rear quarter side wall to allow the winding mechanism from a '71-'73 coupe to be transferred directly into a fastback. Why Ford didn't sell the fastbacks with manual wind down quarters when they were clearly designed to have them fitted is a mystery, but I'm assuming some stingy beancounter worked out he could save $20 per car if they were deleted.

The first step is to buy all the bits needed for the conversion, and eBay is the best place to look. I was lucky enough to find a seller who was selling the complete kit of coupe window parts in one shipment, but the parts can be bought separately, and the following pictures show exactly the parts that are needed (one set only shown - you'll need to buy two of everything of course). The coupe window is not the same shape as the fastback window so cannot be used. For this conversion you will be using your original fastback window.

Shown here are four screws for mounting the winder mechanism, the two upper stops that allow the window to positioned correctly when wound up, and a coupe rear quarter window crank handle. Not shown is the screw that holds the window crank on. Using a front window crank handle on the rears would probably work ok, but these rear crank handles are shorter and won't stick out into the door entry area where the could get snagged by a person getting in or out. If the bolts can't be sourced on eBay then a local fastener shop would probably have them:

window1a.jpg


This is a coupe window winder mechanism; mine is second hand, but these can be sourced as new reproduction items:

window2.jpg


This is the coupe rail sliding plate:

window3.jpg


And this is the coupe window clamp plate with rollers attached (the coupe clamp plate is designed to be compatible with the fastback window):

window4.jpg


An exploded view of the clamp showing all of the parts, in case they can't be sourced in a single assembly this pic shows every part needed:

window5.jpg


and another view detailing the assembly:

window6.jpg


First step is to remove the seat, the side panel, and the rubber quarter post seal from the door jamb. Undo the three window plate bolts (circled):

window7.jpg


The window can then be removed. It is likely that after 38 years the rubber window seal will be stuck to the window so a screwdriver might be needed to pry the rubber away from the glass:

window8.jpg


Then remove the three bolts on the large mounting plate and remove it through the window gap:

window9-1.jpg


Remove the clamp plate from the window by undoing these three bolts:

window10.jpg


Once again 38 years will have glued the rubber clamp pad to the window around the mounting holes, so very gently and slowly prise the window away from the rubber with a screw driver. When the window is free give it a good clean. None of the parts removed from the window will be re-used during the conversion: (EDIT: The rubber clamp pad could be reused if unable to obtain one from a coupe)

window11.jpg


Spray the insides of the rails on the sliding plate liberally with lithium grease:

window12.jpg


Insert the sliding plate though the window slot and bolt it into position loosely to the same studs and hole the original mounting plate was attached to:

window13.jpg


On the new clamp plate remove the lower window clamp bolt and washer, loosen the top two roller nuts slightly (leave the bottom roller bolt tight), spray the rollers with some grease and then slide the rollers on the plate into the rails on the slide plate:

window14.jpg


When the clamp plate has been slid down about 3/4 of the way, undo the top two roller nuts and pull the top of the clamp plate away from the roller screws (letting the clamp plate pivot on the bottom roller to which it is still attached). This is when you attach the window to the clamp and it can get a little tricky. Drop the window in from the top and position the roller bolts into the top two mounting holes in the window. Place the two small nylon spacer bushes into the clamp plate, then place the rubber clamp pad into position on the clamp plate using the two nylon spacer bushes to hang it on:

window29.jpg


Move the metal clamp plate (and rubber pad) into position over the roller screws by pushing the nylons spacer bushes through the holes in the window and put the nuts on the screws. Important: before doing the nuts up tight, be aware that the large metal washers on the rollers (now hidden from sight behind the clamp plate) have flats in their holes that correspond to the flats on the base of the roller screws. Put you fingers around the back of the clamp plate and turn the washers until you are sure the roller screw has located properly inside the washer hole - tightening the screw if it's not located properly in the washer may break the window! If everything looks alright then tighten the nuts firmly, but not tight enough to damage the glass (this particular little assembly job does get pretty fiddly and hard to line everything up easily, but don't be suckered into thinking you can attach the window to the clamp plate and insert the whole lot into the car in one go - I spent about an hour on the first window I did trying to do it this way before I concluded it just couldn't be done....):

window16.jpg


Next is the last window bolt, flat washer and plastic spacer is put in from behind and the nut tightened from the front:

window18.jpg


The two upper window stops are then inserted inside the wall with the bolts done up loosely. The following pictures show where they go, with the slots allowing for window stop adjustment:

window20.jpg


window19.jpg


Now bolt in the winder mechanism; note that only four bolts are used, with the other two mounting holes in the mechanism not needed:

window22.jpg


Connect the winder mechanism arm to the pin on the window plate clamp using a circlip over the pin:

window23.jpg


Temporarily put the crank handle onto the winder spline, wind the window up to full extension. Move the window into the correct position by moving the sliding rail plate slots around on its studs and then tighten the sliding plate nuts and bolt. Then adjust and tighten the upper stops as required (Positioning the window in the right spot can take a few tries).

Now to drill the hole in the interior panel so the crank spline can stick through. Place the panel into its correct position, then looking in through the top you will be able to see where the spline is touching the inside of the plastic panel. Use a scriber or something long and sharp to scratch the panel around the top of the spline so there will be a visible mark on the panel when you take it back off:

window24.jpg


Just to be sure you've marked the right spot, drill a small pilot hole first, then put the panel back on and see if you got it in the right place:

window25.jpg


Choose a hole saw big enough for the centre of the crank handle to slide through with a bit of margin for error, but not too big that the edge of the hole will show if you didn't quite manage to drill in the right spot:

window26.jpg


Now put the car back together, place a plastic crank disc over the hole to protect against winding wear, then screw on the crank handle. I had to replace the rubber quarter post seal on the door jamb too (I bought these before I started the job), as mine was as hard as a rock and wouldn't let the window slide through it:

window27.jpg


Jobs done....now to grow an extra long mullet that I can hang out the new window while cruising on the open road!

window28.jpg


 
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