Monday, October 25, 2010

Engine Work

Rebuilding an automobile engine is a dirty, tedious and thankless task. I know because I did it. Twice.

The first time I did it, I did it because I wanted to. The second time I had no choice.

Choosing to rebuild an automobile engine by myself was a decision made in no small part due to outright hubris, but I can't rule out foolish ambition nor willful ignorance. This sad state of awareness was tempered only slightly by the musings of John Muir, who not only convinced me that I could do it before I did it, told me how to do it; guiding me through the process first bolt to last as though he were there in person.

Muir, of course, did not advocate rebuilding the same engine twice, but he was there for me the second time round with nary a note of recrimination.

His book, How to Keep Your Volkswagen Alive, is considered the precursor to the whole "S&*! for Dummies" phenomenon that swept through the pre-internet publishing world a scant decade or so after Muir's hard-edited typewritten and photocopied manuscript was spiral bound and set upon the Whole Earth catalog for hippies like me.

Muir was prescient that way, knowing that humans needed technology but also realizing that we needed humans to tell us how to fix technology. A couple of years later I read Zen and the Art of Motorcycle Maintenance, where Robert Pirsig explored and expanded on similar themes, so I was primed to work on my car both from a cultural, physcial and intellectual background that led to this desire.

Well, if you ask me, any amount of reading, no matter how much, just isn't enough. Muir's book, fortunately, was less about reading and more about the doing, so when it came time to find this bolt or that nut or just how-in-the-hell-do-I-get-a-screwdriver-on-that?, Muir was my guide. Emphasis is on the word guide, for as much as I concentrated on his instructions, at some point I had to set aside the book and actually assemble things, and that's where it got a bit tricky.

Actually I did pretty well at the tear-down part, but only in terms of speed. My organizational skills were decidedly lacking. For one thing, I didn't label things with anything like the detail that was really required, so even though the result of a week's work looked like I had the damn thing apart and under control, only the former was true. I had the thing apart alright.

Even though it was better than some of the places where I have worked on my bits of metal, including the present spot, my workspace for this engine rebuild was not exactly ideal. I chose to spread the pieces out on several tables under the carport at the the house where we were living. So, even though it couldn't technically rain directly onto my work area, it was exposed to the elements to a degree that made work intermittent and unpredictable even when I did get out there.

One thing that I learned from the experience was about the practical aspects of engineering. When working on a bit of metal as complex as an automobile engine, the consequences of how something has been cast, machined or milled can be serious. The order in which the thing is assembled may not be the way it comes apart, and it certainly is not often the way it is repaired.

Not only did I manage to get the thing apart, I also managed to get it back together.

Though all the details are lost to me already, I know that there were more than a couple of mistakes made along the way. I am pretty sure it took at least two sets of bearings before I learned how to properly 'seat' them in the crankcase, and I know I went through a couple sets of not-so-very-cheap rings before I got them into place. The various seals were not as easy to put in as I'd hoped either, and as a result, there were more leaks from that metal assembly than I have fingers and toes. Thank goodness there is no water system in a VW engine, or that would have leaked good and proper as well.

Suffice it to say that by the time I had the thing back together, I had made every mistake in the book. Plus, I had enough that weren't in the book left over to write a book. That is, if I hadn't already dismissed them all from memory. Muir's warnings notwithstanding, if it took several tries before I broke it, I broke it. To my credit, I did manage to step back from the brink often enough that the various critical systems eventually stopped leaking, grinding and/or scraping long enough for me to declare it finished and put it back in the car.

That, however, was just the beginning.

From the sound of it, the first time I started the engine up might easily have been the last, but for some quick reflexes and plain dumb luck. Instead of bench testing the engine before I put it back in the car, I simply pushed myself hard to get it all back in, wired and hooked up before I settled in and turned the key. Big Mistake.

The sound that came out of the engine with the first three or four revolutions (thankfully it was no more than that) was horrendous, to say the very least. It sounded like I had imprisoned a demon with hammer inside, and it was banging desperately to get out.

I felt sick. After all that work, it just didn't seem possible. What had I done? More likely: What had I missed?

It turns out that what I had missed was a simple little metal washer, about a quarter of an inch in diameter. Somehow--and family 'lore' has it being the innocent act of a small child, but no names will be named--that washer made it's way into the bowels of the engine through an uncovered hole in the block. It had to have happened sometime after the block was back together, but it obviously hadn't made it's way to a critical place before I put the engine back in the car.

I had no idea that a piece of metal that small could sound so loud. The pounding coming from the interior of an engine made me think that the entire guts had just been destroyed. As I stepped out of the car and took a look, the realization hit me. Sadly, the only way to find out what it was would be to tear it all back down.

As I said, rebuilding an automobile engine is hard, thankless work, but never so much as during the time I was tearing my handiwork apart. Two weeks later, through the tears, blood and motor oil filling my eyes and covering my hands, I found the washer, bent double and resting on top of the cylinder head. In spite of all the horrific noise, other than a small semi-circular dent in that head, there was actually no damage to the engine.

The second time, I figured out how to bench test the engine before I put it back in the car, but it was of little comfort to me when it finally passed. By this time I was exhausted and frustrated, which is not the way you want to start off working on the body.

Next: Body work: The bigger hammer

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