Pop Top Arm Repair
If you choose to use this information, or information linked to this page, please understand that you do so at your own risk. Consult your Vanagon Bentley. Information here is based mostly on a 1981 Westfalia, but the wear points and lift assist construction are very likely the same for later model years.
The ends of the pop top push bar are prone to excessive wear. Each push bar end pivots at ends of upper and lower arms. Over time, under normal use, a narrow portion on each upper arm (narrow portion in pic repaired) eventually cuts into the push bar posing the risk of it cutting through completely. General opinion seems to be that these parts should be inspected and repaired sooner than later.
- 1 - Lift Assist Parts Description And Function.
- 2 - Strut Assembly Removal: method 1.
- 3 - Strut assembly removal: method 2.
- 4 - To remove as one piece.
- 5 - To take apart in situ, then remove.
- 6 - Installation of assembly: method 1.
- 7 -Installation of assembly: method 2.
- 8 - Possible issues and tips.
- Lift Assist Parts Description And Function.
Each pop top lower arm contains a cable and spring to provide lift assistance. A recent viewing of ETKA by the author, showed only one set of assist parts but assist parts were likely installed in each lower arm at time of manufacture. Each cable has a bolt shaped part on one end and "Z" termination on the other. The "bolt" seats at bottom of spring, cable passes through spring, exits lower arm, follows the curve with the "Z" securing to a hole. As top is lowered, the "bolt" end of cables pull on the springs. As the springs compress the tops' weight is effectively reduced. As top is raised, the springs expand pull on the cables, thus helping the user raise the top. A existing failed cable may not be detected by the owner. They may not know of these parts and/or have grown accustomed to the weight. The pop top is typically closed most of the time leaving the cables and springs under tension. These cables don't last forever. In time, they will fail. If a cable fails while top is being lowered, the weight of the top suddenly increases.
- Strut Assembly Removal: method 1.
With the top down, bind the upper and lower arms together by passing a suitably sized wire or rope through upper hinge then around lower and upper arms. This wire or rope needs to securely bind the arms together. Failure to do so could result in arms suddenly flinging apart with considerable force. Particularly when assembly is out of vehicle. If more work room is needed, the top can be resting but not latched. Consult Bentley for fastener removal. Remove fasteners at upper and lower bracket hinges, raise and safely support top high enough to provide L/R movement for strut arm assembly removal, remove assembly.
- Strut assembly removal: method 2.
Untested by author. May require clarification. Method offered as alternative to keeping arms folded under tension and may provide insight if one is only replacing a broken cable.
Determine if strut assembly can be safely removed as one piece. (i.e. temporary support not in the way) If strut assembly can't be removed as one piece, it's possible to disassemble in situ as required.
- To remove as one piece.
Raise top completely. The top is heavy. Support securely with temporary support. The springs are now almost totally UN-compressed, so tension is almost gone. Stop pins at top of lower arms prohibit further movement. Remove fasteners and/or hinges. ** If possible, remove lower pins first, then upper pins. Removing arms with upper hinges attached might require the use of a ladder to get at carriage bolt heads. Be aware that installation of upper pins may be difficult due to limited room for push nut installation. It may be possible to install push nut on inward facing side of upper arm.** Remove strut assembly.
- To take apart in situ, then remove.
Before removing fasteners. On one side, remove push nut on stop pin at top of lower arm. Allow arms to fold slightly toward rear. (this tensions spring slightly). Hold push bar steady, remove stop pin at top of lower arm. Release tension allowing push bar to move forward. Caution: with stop pin removed, elbow of arms can now travel further forward. Remove lower pivot pin, rotate arm slightly to rear and up, place tape at end of arm (to keep spring in) rotate lower arm up, remove "Z" end of cable from hole. (Taking things apart this far can allow installation of new cable) Remove cross bolt on push bar, tap arms off end of push bar.
If assembly removed as unit, when on bench, disassemble and check cable(s) for excessive wear. Inspect ends of push bar and hole in big end of upper arm for wear. Repair methods will vary, in part, depending on amount of wear at push bar ends. Regardless of method, installation of a bushing on upper arm is needed to provide a larger bearing surface. Align bushing properly.
Authors pics/text of repair: picasaweb.google.com/musomuso/PopTopStrutCableAndSpringEtc#5501604219504466738
David Beierl's pics/text of repair: picasaweb.google.com/dbeierl/VanagonPopTopHingeTroubles#
- Installation of assembly: method 1.
Pop top safely raised and supported high enough to provide L/R movement of strut assembly, position strut assembly, install lower fasteners, compress upper arm down, remove wire or rope, align upper hinge (lowering top further may help). Install Phillips screws most of the way in, caulk the carriage bolt heads and top where they mate, install bolts mostly tight, final tighten screws, then bolts.
-Installation of assembly: method 2.
Untested by author. May require clarification.
Arms could be left unfolded and installed with top still fully raised. If not.... Fold arms and bind together as per removal method 1. Lower pop top leaving enough room so assembly can be put into position. Support top properly. Follow remaining steps in installation method 1.
- Possible issues and tips.
Preplan for a safe way to slowly release the arms once strut assembly is removed. They are under a fair amount of tension. Needle nose vice grips carefully applied to carriage bolt heads can assist removal. Clean top and bolt heads where they meet, caulk bolts, install. Open driver side slider window to ease removal of carriage bolts. Pivot pin push nuts may get deformed during removal. If worn or damaged, SAE push nuts can be purchased from a good generic auto parts store. Use locking type nuts on push bar bolts. If using method 2, lowering the top down may make strut assembly installation easier. (reverse of method 1) If so, pre plan for some way to safely lower the top. Be aware that you have to bring the arms back together and tie up if installing as per first removal method. If a cable is broken, a possible solution.