This is for anyone interested. I'm in process of getting both doors working ship-shape, and I learned yesterday that putting washers between the door and the lower bolt of the front window guide rail (the metal piece that the big plastic slider on the window glass holder rides in) does wonders to realign the window. I was having just about every problem possible; window was cocking forward as it rolled up, window would stick on a roller and jolt as it moved up or down, window would just flat out jam in mid-travel, window would be angled way out and miss the chrome door sash completely, the works.

By experimenting with different groups of washers placed between that front guide rail and the door sheet metal and then threading in the lower rail bolt, I was able to fix every one of the problems. Tightened up the regulator slop, put the window at the proper angle so it slides cleanly into the chrome sash, and somehow it even leveled out the window almost perfectly so it guides itself perfectly against the seal and seats firmly without the slightest fight.

I ended up with three washers total, I'd guess about 3/16" worth of material. Pain in the arse to slide them in place, but it really did the trick. I don't know if this means the old regulator assembly is just old and loose, or if the plastic sliders are worn, or whatever else. Just know it worked, so if you're having problems with the window motion give it a shot.

any chance you had some pictures of this? I have having these exact issues with the passenger window right now

Now ya tell me! :stupid: I fought that problem for about 25 years and I would guess at least 6 or 7 window regulators, I could get the alignment close, but eventually over time the regulators would bend and that would be that... (I still have 2 spare NOS regulators sitting up in the garage).

Finally about 2 years ago, I came up with the same solution that you came up with. It's been working perfectly ever since.

BTF/PTM: Thanks for the tip. I needed to adjust both window regulators and reglue loose felt channels in both window sashes over the last three days on my 1971 240Z and the passenger side window had all of the mis-alignment, jolting and jam issues that you described even after readjusting the front and bottom guide rails. I inserted a 3/16" thick nut (much easer than using three 1/16" washers) at the lower bolt of the front guide rail between the guide rail and the door and, presto, everything was realigned perfectly. I added a 1/16" thick washer on the inside face of the door on the upper bolt for the front guide rail to eliminate the jolting. The window nows goes up and down very smoothly. What you did not mention is that you need to substitute 1/4" longer bolts to accomodate the spacers. To everyone else who is having similar problems I highly recommend BTF/PTM's solution!

I did that same exact thing to my regulators about 10 years ago... Still working great.

think that will fix my problem here?

 

gave it a try, I put two washer, maybe 1/8" total between the front guide rail top bolt and door skin, effectively angling the window more outward as it traversed the guide.

I tested this out by 1st just loosening the lower bolt a little and the upper bolt a lot, then I could push on the head of the top bolt and observe how it effected the window, making it angle outward. Glued to washers together and carefully pushed them inside the door and guide. once they were started I was able to use a pick to grab them from the opening in the skin and pull the hole of the washers into place. No washers were used on the bottom bolt.

results are promising, I will post up another video tomorrow. Beats the he!! out of completed pulling all the parts out for a maybe fix. Considering how little use the windows get, I will be happy if this does it. I will still replace the channel felt in the sash both upper and lower. I did my best to get lithium spray grease on all the moving parts including guides and wheels.

Great tip!

There are subtle differences between the 240 and 74-76 280 regulators, guide channels and window guide frame that might explain that Nissan was also trying to improve the geometry. The regulator frame is about a 1/4 thicker and moves it away from the door frame by that amount.

The final solution is the vastly different and much better window guide rails in the 77-78 doors that finally fixed the problem. Many modern doors still use this basic  system of two vertical guide rails. The regulator is basically unchanged except in how it affixes to the glass. 

As usual, getting the basics right first, means fewer degrees of freedom for the other components. Good tight fitting felts in all the channels, and proper lube and free movement of the window in its guides. Once the window CAN move freely up and down without slop, THEN the guides can be tweeked to make it move in the geometry that makes it fit the frame when its up.

 

 

I have the new lower felt on the way, I hope I can pull the door sash (think that is what they call the frame that has the felts inside it) with out having to remove the window or regulator. The lower felt was shot on the back of the sash that extends down deep into the rear of the door was shot.

58 minutes ago, Dave WM said:

I have the new lower felt on the way, I hope I can pull the door sash (think that is what they call the frame that has the felts inside it) with out having to remove the window or regulator. The lower felt was shot on the back of the sash that extends down deep into the rear of the door was shot.

Unlike the skilled Nissan techs, I was never able to master removing the window without first removing the frame.  So... removing the frame for your replacement felt should be easy peasy.  No need to touch the window or regulator.

after the trick..