Pop Top Arm Repair
Note: this article is still in edit mode. I hope to have it fine tuned soon.
Given that these parts support a fair amount of weight, use this information at your own risk. Consult your Vanagon Bentley. This information is based, for the most part, on a 1981 Westfalia but to the best of the authors knowledge, wear points and assist construction is the same for later model years.
The ends of the pop top push bar are prone to wearing through. Each end is housed in a pivot point between the upper and lower arms. The relatively narrow end of each upper arm eventually cuts into the push bar posing the risk of it cutting through completely. The hole on this part of upper arm also wears as it rubs on the push bar ends. General opinion seems to be that these parts should be inspected and repaired sooner than later.
Parts description and normal operation.
The pop top arms contain a lift assist system; a cable and spring in each lower arm. The author recently viewed a version of ETKA showing the Westfalia having a lift assist only on one side. It's likely the factory installed one on each side.The cable has a large bolt shaped part on one end, and "Z" termination on the other. The "bolt" seats at bottom of spring, the cable passes through spring, exits lower arm, follows a curve on big end of upper arm. The "Z" secures to a hole. On each side, as the top is lowered, the cable pulls the spring open tensioning the springs. Tensioning of the spring effectively "takes some weight off" the top. As the top is raised, the springs are allowed to contract. This aides in lifting. Some Westfalias may have failed cable(s) so one or both springs may not be assisting the user. It's possible most owners don't know of these parts. Since the pop top is typically closed most of it's time, the springs stay expanded, putting the cable and springs under stress.
Strut assembly removal: method 1.
Top down, secure upper and lower arm together at bracket ends with a suitable wire or rope. If not enough room to work, top can be resting but not latched. Ensure that wire or rope is passed through upper hinge then around lower and upper arm so it won't slip down the arms. If this happens, the arms will spring apart with considerable force. Consult Bentley for fastener removal. Remove fasteners at upper and lower bracket hinges. Ensuring pop top is safely supported, raise it enough to provide L/R movement for strut arm assembly removal.
Strut assembly removal: method 2. Untested by author.
Raise pop top to full height. Support properly with temporary support. Tension in springs will be almost totally released. The stop pins keep arms from moving any further at joint. Remove fasteners and/or hinges. If temporary support is not in the way, there may be enough room to take out strut assembly as one piece. If not, on one side, remove the stop pin, allow lower arm to release any remaining tension. Remove "Z" end of cable from hole, remove nut/bolt. Tap arms off end of push bar.
With assembly on bench, disassemble as per steps above. Check cable(s) for excessive wear. They do fail. When a cable fails, and user is lowering or raising top, weight of top suddenly increases. Inspect ends of push bar and hole in big end of upper arm for wear. A bushing made of bronze or copper can be epoxied in hole on upper arm. Better yet, weld in a steel bushing. The bushing will act as a bearing and spread out pressure. Lubricate these parts. Though likely not needed, the author epoxied a piece of 5/8" bolt into the push bar ends to add support.
Authors pics/text of repair: picasaweb.google.com/musomuso/PopTopStrutCableAndSpringEtc#
Possible issues
Pivot pin push nuts get deformed during removal. Both sizes of pivot pin and push nut can likely be sourced from a generic auto parts store in SAE size. If using method 2, pre plan for some way to safely lower the top. IT'S PRETTY HEAVY. Preplan for a safe and slow way to release the arms once on the bench, then unsecured. They are under a fair amount of tension. Be aware that you have to bring the arms back together and tie up if installing as per first removal method.
Installation of assembly: method 1.
Pop top safely raised and supported to allow room to put assembly into position, install lower fasteners, slowly release the arms, line up upper hinge (top may need to be lowered for this to line up bolt holes). Install Phillips screws most of the way in, caulk the carriage bolt heads. Install bolts mostly tight, final tighten Phillips then bolts.
Installation of assembly: method 2.
Fold arms and tie together as per removal method 1. Lower pop top, but leave it open enough so assembly can be put into position. Support top properly. Install lower fasteners, slowly release the arms, line up upper hinge (top may need to be lowered for this to line up bolt holes). Install Phillips screws most of the way in, caulk the carriage bolt heads. Install bolts mostly tight, final tighten Phillips then bolts.
