Tuesday, August 21, 2018

Ignition Re-Assembly

In my last post, I described the tear-down of the ignition assembly of the old 1972 VW microbus. Today's post covers the re-assembly.

Some Part Suppliers Are Better Than Others
I mentioned that I found a bus wrecker in Washington who sold me a lock housing for $75 plus shipping. What I learned when I opened the box was that the lock housing came with an original key cylinder and key. The seller had stored the housing, cylinder and key all oiled up and in a zip-lock baggy. The key works the mechanism flawlessly. They included the small set-screws which hold the housing into the black box. Avery's Air Cooled, you rock. I wish I'd found you years ago. You'll be my first call now.

Lock Cylinder, Housing and Sub-Harness
new plug has exposed
solder so I taped it off
The Bentley has re-assembly instructions. I tried them. They didn't work. The book says to install the housing, then put in the lock cylinder and then, once everything else is in place, install the electrical sub-harness. Yeah.. that last bit doesn't work. The harness is constructed so that the wire bundle comes out to the side, not straight out. In general, that's good, but once you orient the plug to the housing, you realize that the wire bundle comes out the completely wrong way, running almost rear-wards. Holding the housing up with the plug facing you, it comes out around 4:30. Ideally it comes out around 9:00. So, to plug it in, and have it click home, the wires needs to double-back on themselves in a very tight area while you are somehow applying leverage for it to snug in. Physics just won't comply.

So, we do it differently. Before I started, I removed the lock cylinder from the housing and test fit everything. First the harness, then trying the lock cylinder first to see if there were any serious issues with doing the lock cylinder last. Nope. Since the harness was already wired into the bus, all of this was done using the driver seat as a work bench. So glad it's Summer, by the way. I plugged the harness into the lock cylinder and made sure it clicked home. There is only one way to get this all the way seated, with a larger tab fitting into the larger slot and a smaller tab into the smaller. I even tested whether the key, housing and sub-harness would trigger power, so I hooked up the battery and turned the key to the run position. I could hear the click-click of things getting juice, so I considered the test a pass.

Into Darkness
turn signal wire bundle
With the harness in the housing, we now twist into a pretzel to fit the housing into the black box. For reference, consider that the entire steering post, etc had been back together only to discover that the old housing wouldn't work. Recognizing how difficult the tear down was before (3 full days), I wasn't going to do that again. So, the black box is on the steering column with the rubber bushing, and such in place. The housing takes some fiddling to get into the right orientation, in part because the harness is plugged in, but mostly because it is not exactly parallel to the bottom of the black box. It tilts up to the right (towards the key opening). Once the tabs find the slots, you need to press the housing firmly as deep as it can go into the slots while tightening the set screws. This took a few tries, but once it was in the right place and the set-screws cinched down, I could start to see the light out of the dark

Key Lock
With the housing in-place, the lock cylinder can slide home. This is a do-it-once kind of thing. If everything isn't lined up right, and you need to pull the lock cylinder again, its a multi-day job. Things looked good, so I slid it home. It fortunately had no issues.

Other Discoveries
In my case, we believed the ignition fry was caused by either the heat/defrost fan or by the headlight switch. So, I removed the wiring for the heat/defrost fan and replaced the headlight switch. As happens these days, the headlight switch was faulty out of the box. I had to wire both the running lights and the headlights out of the same pin because the pin for the headlights simply didn't work. Also, the new switches don't come with a pin for the idiot-light on the dash, so I wired that into that same pin. Now, when I pull the stalk out one spot, the running lights, headlights and idiot light all illuminate. Nice.

While I was removing wires for the heat/defrost fan, I installed a new switched 12V wire along the same route. Following older VW coloring, I used black, and tied it into the furthest right fuse, the switched 12V for the coil used to come from. Now, when I turned the key to run, I have a nice strong signal for the new-engine electronics. But there was more darkness ahead. I'll get into that next time.

Thanks for following along. I'll wrap this up next time

1 comment:

PdxPaulie said...

After sitting over the winter, the switch did not work when I tried to start Hapy. I will post on how I solved later. Not sure what caused the failure, but now I have 2 keys for Hapy: one to unlock the steering and one to start/run. Neat.