This project took some time, not because it is an extremely labor intensive project but rather because I included my daughter. Although it is a lot of fun to team up with her and a great joy that she is interested in working on Moby, she inevitably prolongs the time frame required. I actually replaced the regulator weeks ago and have waited for her to help put the door back together and take the final photos ever since. Who would have thought scheduling time with a 6-year old would be so difficult! I finally got tired of waiting and, with cold weather settling in, needed to get the vapor barrier glued back to the door under favorable temperatures.
Typically window regulators (also referred to as the lifting mechanism in the Official Service Manual by Robert Bentley (OSM) fail due to a stripped gear or broken weld where the window attaches. In the case of the latter, they can usually be welded back together. In the case of the former, you cannot fix them, at least easily, because they are pressed together, not bolted or screwed. My experience with these parts involves two regulators failing with the window still open at the worst possible time; one (on the Big Red One) at the start of a 4-hour winter ride in 20 degree weather and the other (on Moby) just before our trip to Assateague last summer. The quick fix requires taking the door apart, unbolting the window from the regulator, pushing the window up, and then inserting a thin wood block of the appropriate length to hold the window closed (not bad actually as long as you have the block). Regulators are a bit difficult to replace, well maybe I should say tricky as I am sure if you did couple every so often the procedure is less of an issue. But, if you are like me, you replace them once in a great while and cannot remember how you did it the first time. It is this project that actually convinced me to write this blog; not only to record the adventures but to record procedures for these infrequent projects. Next time, I can just look up here!! (Of course this guarantees that my regulators will never fail again)
I picked up a replacement regulator at the local bone yard (you can also by them new) which was fairly stiff to operate sans window and sounded like someone threw a bunch of sand in the winding. I worried that once installed, with the added resistant from the window, it would quickly fail. Getting all the grit and old congealed grease out took a bit of time, a small brush, and a fair amount of mineral spirits. Once clean, I packed the winding with some multipurpose grease. It now works so well that I am tempted to clean and grease the passenger side.
The first step in replacing the window regulator is taking the panel off the door. You may already have this accomplished if you “fixed” the window to keep it shut. But if not, you will need a philips head screw driver to remove the plastic frame around the door release lever (see OSM 5.3, p. 11), door handle, and window crank. Once these items are removed, use a soft, wide, thin item to gently pull the trim panel off the door. If the item is too hard it can scratch the paint or if too narrow it can deform the panel; l found a plastic putty knife works great. Remember, the panel is only pressed cardboard so be gentle!! It is very easy to rip the retainer clips out of the panel!
Once the panel is removed, you can access the plastic door liner (vapor barrier). The first time I did this, the liner was in tatters so I just ripped it off and replaced it with plastic sheeting from the local hardware store. On Moby, the liner was in great shape so I gently pulled the edges off the door; the adhesive used allowed the plastic to come off and not tear if pulled very gently. Here is a good run down on replacing your liner if needed.
With the plastic out of the way you can get at the six bolts holding the regulator in place. Their locations are shown nicely in the OSM 5.8, p. 14 (note: the two bolts which hold the regulator around the window crank are seen in Figure 5-19). You also need to remove the two bolts holding the window to the regulator. To do this, roll the window (you will probably need to push on the window) 1/2 to 3/4 of the way down. Go too far and you will not have great access to the bolts. With the window detached and resting in the bottom of the door you will need to be careful not to scratch the glass during the swap. Unfortunately, I did not pay close enough attention and put a tiny scratch in the glass during re-installation of the regulator. With all those bolts removed you should have a loose regulator but it will not come out quite yet.
If you look up in the door you will see that the front window guide channel, the lower extension of the vent window frame, is attached to the door frame. The regulator must pass between the window guide channel and door frame to come in or out. If you are replacing the window/vent seals like I did with my red 71, then this should not be an issue because you will remove the vent window, channel and all. However, if you are not then you need to create some space.
The OSM is a little confusing on the next step, stating simply to “press the window front guide channel forward off its bracket” and then slip the regulator through the resulting gap. Forward normally refers to the front of the bus but the channel cannot be pushed in that direction without tilting the entire vent window and frame, i.e. removing a good portion of the window seal. The consensus I found on sites like The Samba is that the OSM assumes the door is open and that a “forward” motion now results in prying the channel off its frame mount towards the outer side of the door, which, when the door is open, faces the front of the vehicle. Taking clear pictures in the small confines of the door with all the tools and the regulator to illustrate this process step-by-step proved impractical but I included modified photos to try and clarify the following procedure.
For the prying phase of this project, I grabbed a plastic wedge intended to help free chain saws bound in trees and a scrap piece of maple leftover from when I put new floors in the house. Before starting, you must remove the bolt holding the window guide channel in place (see Figure 5.19 mentioned above). Using the plastic wedge first, I placed it at the bottom of the door frame underneath where it meets the guide channel and pushed up with my hands. The wedge worked great in terms of separating the channel from the door frame, but the angle of the wedge shape was too shallow. This resulted in too much of the wedge occupying space in the gap between the channel and door frame and thus prevented the regulator from moving through the gap. The plastic wedge, however, did allow me to understand what I needed to do and how forgiving the door/channel was when pried.
I had more success with the scrap wood on which I cut an angle (close to 45 degrees) on one end. With the sharper angle, I could no longer force the guide channel and door frame apart by hand and needed a hammer. Once the gap formed, the wood stayed out of the way and allowed the regulator to enter the gap. With the regulator in position between the channel and door frame, I slid it out together with the wood (the wood must come out as it blocks the path for removing the regulator (see photo with yellow arrow above)).
To install your new regulator, simply drive the wood block back between the guide channel and door frame. In doing so, the gap is blocked by the wood and you cannot get the new regulator into position. To solve this, I found a bolt slightly wider in diameter than the regulator and fed it through the door and into the top of the gap above the wood. Holding the bolt in place, I removed the wood which caused the guide channel and door frame to close around the bolt. I then took the new regulator and moved into the bottom portion of the gap. Once started, I pushed the regulator as high up into the gap as possible and then pressing the regulator against the bolt, put the plastic wedge under the regulator and hit it with a hammer. I repeated this process until the bolt and regulator popped out the top of the gap and then removed the plastic wedge allowing the channel and door frame to come back together. Now it was simply a matter of positioning the regulator, installing the retaining and channel bolts, window, testing the regulator to make sure it all worked smoothly, fixing/replacing the vapor barrier, and, finally, installing the trim panel, window crank, door handle, and door release lever.