Window Stop
 

Ok,

I'm over the edge now - I decided to remove the regulator so I could see the entire assembly.

Here's what I'm getting at - in the following photo, you can see that the type of regulator that's installed in my car has a lower stop bracket that isn't present on most (?) 911 regulators.

http://forums.pelicanparts.com/uploa...1517772906.jpg


The stop that's attached to the lower bracket is not adjustable (has small nubs that fit into 2 holes in the lower bracket):

http://forums.pelicanparts.com/uploa...1517772943.jpg

Bottom line -vehicles that have this type of regulator (with lower stop bracket), will have windows that don't go down as far as those that have the non-stop bracket type regulator...

OBTW - yes, my spring retainer came loose... Looks like I will be fixing as per this idea: http://forums.pelicanparts.com/porsche-911-technical-forum/664473-slow-window-fix.html
Gordo

Window Regulator Spring Retainer Repair
 

My version of the window regulator spring retainer repair - using stuff I found around the house...

- Small section of metal tube cut to ~ 3/4"
- Small carriage bolt & nut (the square head of the carriage bolt was a close fit - needed to be hammered into the rectangular cut-out where the original retainer was mounted)

http://forums.pelicanparts.com/uploa...1517786594.jpg


http://forums.pelicanparts.com/uploa...1517786611.jpg

With the spring retained in the original position and properly tensioned - the window goes up a little faster / easier.

Gordo

My targa doesn’t have that regulator, with the lower stop. The replacement part I put in also does not have it. What’s the part number on that regulator? It appears to me you may have the wrong one.

When the top rail really gives up the ghost, the window doesn't go down freely and hangs up on the channel causing it to crash down unless properly guided. Also on the way up it digs into the weather stripping in the channel and causes grief. This happened to me and my wife while on a trip. New top rails are not cheap but seem to be the one area in the system where water accumulates and has no means of drainage. Perhaps the rust holes are a good thing....LOL

As mentioned - it appears that this style regulator was used in some (possibly few) SC Targa's and Cabriolets (based on info in the Bentley manual). The lower stop type regulator also appears here: https://www.porscherepair.us/porsche-911-guide/adjusting-door-window-targa.html

Image from linked website:
http://forums.pelicanparts.com/uploa...1517887749.jpg

The part # is 91179954202.

I'm guessing the type of window regulator used depends on what the factory had in stock at the time of the vehicle's production. Apparently they had the lower stop bracket style in stock when they built mine (1983).

Been there... Your comment did make me consider another theory on why Porsche installed the lower stop bracket style regulator:


---------------------------------------------

Another theory on why Porsche may have tried the window regulator with a lower stop bracket:

- With the lower stop style reg, the windows never fully retract into the door. As such, the top of the window can't recess lower than the door's weather stripping / "scraper" (the part that is inserted into the top of the door frame).

- The lower stop design reg reduces wear on the weather stripping / scraper. The top of window can't get below the bottom edge of the scraper (covered with a felt like material), and push it upward, causing it to deform or move out of position and result in damage and wear.

Gordo

Interesting. Given the two choices, I'd go with a regulator without the lower stop and deal with the damage to the scraper (which is relatively minor anyway). Not being able to go all the way down with the window is annoying to your left arm.

Just to follow-up and add 83 Cab-specific info to this great thread...

I've just completed rebuilding my driver's side window / regulator due to the window coming out of the channel and dropping into the door. I have a separate thread on all of that and the process of re-assembly so I'll focus on the regulator stop here.

The lower stop on my regulator was completely broken apart and laying in the bottom of the door. The top stop was in place and I properly adjusted it a few years ago. I ordered a new lower stop and the plastic insert from our host.

I discovered exactly the same thing as the OP - with the lower stop installed, no amount of adjusting the mechanism would allow the window to lower all the way. In my case, the front part of the window is about 3/4" extended and the back is hidden. The window rolls up and mates with the top and the quarter window perfectly.

I also prefer the clean look and ability to comfortably place my left arm on the door top! So I removed the lower stop - this allows the window to lower more than enough to hide. I think I might attach a small stop inside the door at the rear window track to act as a positive stop at the correct height just to reduce the need to think about not lowering too much.