Tuesday, August 28, 2018

Hapy Rides Again

My last 2 posts have been about my efforts to resolve the electrical melt-down we had on the way home from 4Peaks. Today, we hit bottom and work our way back to operational.

No Start
With so many good signals, I wanted to try starting the engine. So, I turned the key to run and nothing happened. At first, this was because the wire to the starter (circuit 50) out of the ignition wasn't connected. Once that was solved, things got worse. I tried the start again and everything went dead. Nothing worked. I went around to check the voltage on the battery and it was crazy low, like 5V. Huh? While watching the voltmeter, it climbed back up to 12.5V. I checked other circuits and they started to show 12V too. By the time I had worked by way to the front of the bus, everything was working again.

I was able to demonstrate this a few times, and it seemed like no matter what wires I tested, I couldn't find a new burned wire. "Could the starter have fried," Boo asked. Why, yes. Yes, it could have. Since so much power routes through the positive post on the starter, the electrical fry that smoked between my knees could have caused a short there too. So, I pulled the starter and tried a ShadeTree starter test.

ShadeTree Starter Test
First, I checked for resistance between the positive and negative sides of the starter solenoid. It was infinite, which told me that the solenoid was probably fine. Still, I couldn't find a good recommendation for testing the starter motor on the internet. Most folks encouraged various tests while the starter was in the car. Mine was on the ground, and I wanted to test just the starter motor without all the other variables. So, I tried my own ShadeTree bench test. I grabbed an old battery that I had lying around. It had around 9V charge. That's enough to trigger the start, but not enough to do much else.

I took my jumper cables, and clipped one black end to the mounting ear (ground) and the negative battery post. I clipped one red end to the positive post on the starter and the positive battery post. I double checked the voltage. No change, indicating again that the solenoid is not blown. If it had been the solenoid, I would have expected current to travel through the starter all the time (solenoid broken with the current open) or none of the time. I worked the leads for the multi-meter into the clips on the starter so I could see how voltage changed when I triggered the start. Using a short section of insulated wire, I touched one stripped copper end to the positive post on the starter and the other stripped copper end to the trigger tab.

The starter did not fire, but the voltage dropped to almost 0. I immediately removed the trigger wire and watched multi-meter. The voltage climbed slowly, but steadily back to 9V. Yep. That starter got toasted, but the solenoid was doing it's job: open the circuit to fire the starter when 12V (or in this case 9V) is applied to the switch. I phoned over to the no-longer-local VW Friendly Auto Parts Store and they had one for me on the following Monday.

Assuming the starter was fried during the initial issue, replacing it should be fine. What if the starter was fried by my test-start because something else was still wrong? Then, the next test-start will cause the new starter to fry as well, right? Eek.

My fears, ultimately, were not realized. I swapped out the rebuilt Bosch I installed less than 3 months earlier with another rebuilt Bosch from Discount Import Parts (still only on the east side... and still not Hapy about it). I followed the instructions I laid out back then, and the test start provided the same disheartening click noise. So, I removed the starter and performed a very similar ShadeTree test. I used the battery and battery-to-starter cable from the bus for the positive side. I clamped a black jumper cable on the negative battery post and to the mounting ear on the starter for the negative side. Using the same little jumper wire from before, I triggered the starter and it fired. So, I haven't re-fried a starter and so maybe some of the wiring has been improved. But something remained. So, I looked at what was still an unknown around the starter while I re-installed it again.

There's the 30 circuit (always hot) that runs to the front of the bus from the positive post and there's the trigger signal plug (circuit 50). I checked the 30 circuit first next because I felt it would be easy to rule it out. The 30-circuit is a red-with-white-stripe wire that runs from the starter positive post to the fuse box. In the Bentley book it is labeled as a "4" thick. That's in cubic millimeters and translated to AWG 12 (see my handy conversion reference here). The plastic on the wire near the fuse box was a little melted or swollen from the ignition failure, but I assumed (possibly a mistake) that it was just from being near the issues and that it was fine. To prove it wasn't an issue, I tried a few things. First, I did a continuity test to show that the wire didn't have a break in it. I believed that wasn't the case and the continuity test proved it. Resistance tests didn't show anything either (very low resistance). I didn't want to run voltage through that wire again, so I ran a long wire from the positive post on the battery along the ground under the bus through the driver door and into the same spot on the fuse box as the red-white stripped wire. This eliminated that wire from the equation as a variable. Then, I tried to start again. Just a "click" again. I tried swapping out the "50" wire that triggers the starter to fire. "Click".

Clumping the Circuits
In the interests of reducing variables, I considered the wiring as 3 large units or clumps.
There's "front-of-bus": that's the original wiring, including the ignition switch, fuse box,etc.
There's the "back-of-bus": that's the '98 NewBeetle engine related wiring. I include the battery in the back-of-bus not because its in the back, but because there are lots of wires routing to the NewBeetle stuff and only one heading to the front-of-bus.
Last, there's the "accessory" that is the deep cycle battery that powers the cabin lights. The accessory is completely separate, only connected by a common ground: the bus chassis. So, we rule that out.
If we consider that the front and the back only connect through a few wires, and I just tested replacements for them above, maybe we can unplug those and test. So, I disconnected the trigger wire for the starter (50), the always hot wire from the starter (30) and the signal wire for switched power (15) from the front-to-back connections, completely separating the clumps. Using my remote starter, I tried to start. "Click". From this, I concluded that the issue was not a front-of-bus problem nor a connection between problem. It resided squarely in the back. That's when Boo dropped by to see how things were going. "Could the battery have gotten affected," she asked. I had been checking voltage and it had been consistently 12.5V, but maybe there just isn't power (amps) behind that voltage. So, following that question, I put the battery on the charger.

I left the battery charging at low amps (2A setting) overnight while Boo and I went to catch the new Incredibles movie. The next day, I re-set all my wiring was back at normal (front-to-back returned, nothing left unplugged, etc), and verified that the battery charger was complete. Everything looked good. So, I tried the new key. It fired right up. Ahh... much rejoicing.

Dollars and Sense
old housing,
melted and hammered
In the end, we add one starter ($160) to the total of the running costs from the last post, and we're approaching $1000. That's pretty darn expensive, but I can't say it was because of either owner neglect nor because of the engine upgrade. The interfaces between the front and rear of bus are very few, insulated with fuses or relays and weren't part of the problem. Ultimately, 50 year old wiring eventually fails. I need to commit to a complete rewire one of these days... but not while there's camping to be had this Summer. As to the total cost, if I remove the wiring harness I didn't need, the cost of the hotel that was just a bad timing thing and the steering wheel I chipped due to being dumb, this electrical repair cost me $295US ($85 for new housing and switch, $25 sub-harness, $25 headlight switch which is another whole story, $160 new starter) plus a $300 tow.

I do want to point out that the 2 major failures found along the way after the original ignition was solved were both identified by Boo. Obviously, she's amazing, but this also serves to illustrate something so important on projects like this: this is a team sport. You need input from a random friend leaning against the fender while drinking a beer pointing at stuff and asking questions. Or, a helpful wife wandering over with a lemonade innocently asking if the starter or battery could have been affected. I'm looking at trees, and she asked about the forest. Brilliant.

That's the end of the ignition smoked saga. While we may have missed String Cheese in the bus, it looks like our other musical (and simple summering) events can include Hapy. Thanks, as always, for following along.

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