'68-'73 to '74-'79 Westfalia Pop Top Conversion

by Jim O'Hara

From the LiMBO newsletter "The Transporter" v6 n3 June-July 94:

Pop Top Replacement Guide

(Arizona member Jim O'Hara sends this article "covering" pop top swaps)

It is possible to exchange the old style pop top (the one with the really uncomfortable cot) with the newer style that has a large double bed. For comforts' sake it makes all the difference in the world and pretty much maintains the stock look, but it's not an easy job.

Before attempting this, I called just about anybody I thought would know if this had been done before, only to find that everyone had heard it could be done, but they didn't know for sure. One guy even told me the easiest way was to chop off both the roofs at the pillars and weld the new one on to the old one! I decided the only way to find out for myself was to go to the junkyard and look. Contrary to popular belief, the pre-'74 and post-'74 pop tops do not have the same size roof holes and the hinges are located at opposite ends of the bus. I figured I could deal with these details and since I found a nice top with a decent canvas I bought it. The rest of the job took several weeks and probably 75 hours of labor, but just in case there are any other masochists out there I'll outline the steps I followed for the rest of the job:

Find a top with a good canvas, seals and all the necessary parts (including cushions). Take pictures of how everything looks and works, and draw diagrams of everything that looks like you might forget how it should go back together. Now is the time to really think: "Is this worth the trouble?"
Pick a nice day and plan to spend the entire day at the junkyard. Make friends with the people that run the junkyard because you will need help lifting off the new top and moving it around. Remove the top and keep all the hardware and the wooden boards that form the base of the bed. Keep track of where all of those hundreds of nuts, bolts and screws came from. Afterwards, study the roof of the bus you took the top off of. I made a template with newspapers to locate the correct positions of the holes for the hinges and the luggage rack. The top itself is really heavy, you may want to brinig a pickup truck but I just threw it on top of my bus, tied it down and drove away. You'll have a fun ride back home.
Remove the folding support arms from the new top and patch any holes in the canvas.
Remove your old top, saving all of the hardware and the old seal. This requires removing all of the ceiling panels, so I took the opportunity to refinish all of them and add some insulation. I also removed the sink and fridge unit for extra space. If you want to keep yours, you may have a problem with the vent pipe getting in the way. Alternatively, you can install the full interior from the donor bus if it had an intact interior.
Use the templates to drill new holes in the rear for the hinges. Put the new top on and attach the hinges. I used plenty of washers on the inside to spread the stress some and some on the outside to raise the whole top to add clearance. A milk crate works well to hold the front up enough to get at the hinges.
Attach the folding support arms to the fiberglass roof and drill holes where they need to attach to the bus roof, noting how much material is going to have to be ground away to give them enough clearance. Scribe the area to be ground away and get out the grinder. After cutting the metal, I bought some plastic trim that goes on the edges of car doors, and put it on the sharp edges. I lined the bottom of this area with some of the rubber seal from my old top laid flat and glued down. Doesn't look too bad.
Take off the metal arms (watch the springs) that hook to the bottom of the folding supports to hold the top closed. Shorten them with a hacksaw so they will hold the new top down.
Lay out the metal pieces that hold the canvas to the bus roof. Use a few of the screws and tape to temporarily attach the canvas to the metal pieces. Mark the place on the roof where they need to be and drill all of the holes. Don't really screw it down yet.
Lay that big flat board on the rounded roof and figure out how you are going to make a bed out of that! I did it by cutting Styrofoam into the right shape to support the board and then wrapping it with duct tape. Then I attached 6 hooks to the board, one in each corner and two in the middle. I also attached 6 round eye bolts to the roof in corresponding locations and used turnbuckles (available in different sizes at any hardware store) to join them together. By tightening the turnbuckles you can adjust the position of the big board to allow the roof to close. After a lot of adjustments and hassles, I finally got it just right by shoving the Styrofoam wedges in exactly the right places. There is enough clearance that you don't have to cut the board. Then I altered the front section of the bed by cutting the board a little for clearance and changing the places where the brackets attach. In order to make the big board even with the little board you have to build little platforms about three inches high and attach them to the roof. I made it up as I went along, but the final result is that with the top down, the front board is in place (but not locked) with the cushion off. After you open the top, you secure the front board by locking it in alignment with the big board by using two sliding bolt type locks (again from a hardware store) and snapping the cushion on. If you are not using the bed but have the top up, you simply fold the front board back over the big board out of the way. This system works very well and is not as complicated as it sounds.
The front luggage rack is probably the hardest part of the whole project. It is impossible to scribe correct locations for the holes which the brackets mount to because the fiberglass rack covers everything. I attached the brackets to the rack with screws, and put glue on the bottom of the brackets where it meets the roof. I put the rack in the right position and let the glue dry. Then I carefully removed the screws and picked up the rack, leaving the brackets glued in the right place. Then I drilled my holes to permanently attach them. Easier said than done, you might find a better way or use a template.
Seal up all the extra holes in the roof. Silicone worked great for me. Contact lens wearers read and heed the warning label on the tube. Silicone residue stays on your finger for days and is a severe eye irritant. When you wash your contact lenses, silicone gets on them and you will know it!
Connect the canvas to the roof using the 700 tiny screws.

It was a lot of tedious and time consuming work, but worth it for me. The bed is plenty big enough for two and very comfortable. It doesn't leak at all and since most of the parts used are Westfalia, it looks fairly original. The hardest thing is getting everything to fit under the top when it is folded down, as there is considerably less clearance than the old one. Be creative and you can find a solution.

Jim O'Hara
Tucson, AZ