Saturday, November 18, 2006

Minding Your Own Business

Growing up in a small central California town during World War II had a curious effect on my age. If you were big enough to do a thing, you were expected to do it, how old you were wasn’t a consideration. That rule saw me driving a tractor when I was eight and piloting the Model-T into town on errands, a feat that made my older cousin David wild with envy for he couldn’t crank the T-model, nor was he tall enough to reach the pedals. He assumed the role of co-pilot. I was a big kid so the cranking and driving fell to me. I didn’t think it exceptional, it was the natural order of things.

A typical chore was picking up chicken mash at the feed store or repair parts from the Ford dealer. Once we carried home an irrigation pump from the machine shop where it had been fitted with a new impeller. The pump was so heavy the front wheels of the Model-T came off the ground when I crossed the railroad tracks. Naturally, we had to back up and try it again.

Such errands never involved money. Back then, the economy of every small town ran largely on trust. Everyone knew my grandfather, who paid his bills promptly the first of each month.

When running such errands we were always admonished to ‘mind to your business.’ As my grandfather’s agents we were duty-bound to make no side trips and to offer no rides, other than to ladies burdened with packages. We couldn’t even buy ourselves an icy Dr. Pepper unless the necessary nickels needed to do so were provided along with our instructions.

We were told what had to be done and left to get on with it. Our ‘business’ was to make a safe, successful trip to town and back. And we took our business seriously, aside from catching a little air now and then.

After bringing home a rebuilt or repaired part, the next step was to dismantle it in order to clean it. New, ready-to-use parts were rare things during the war and even those required cleaning since the cast iron was usually coated with protective grease. Aluminum parts were unheard of. Like the chrome-based green dye on packages of Lucky Strike cigarettes, aluminum too had gone to war.

The need to clean a part before installing it remains valid today although many aluminum parts are wrapped in protective paper instead of being coated with preservative. But a heavy preservative similar to Cosmoline is still used to protect new sets of Volkswagen cylinders & pistons and it must be removed before the parts can be used.

About twenty years ago I saw a fellow rebuilding a Volkswagen engine at a local garage. He was plucking cylinder assemblies right out of the box and slapping them on the engine. No cleaning. No inspection. Thinking he didn’t understand, I pointed out the need to clean them and was told to mind my own business, along with an ear-full about the hundreds of VW engines he had built and his many years of experience. The fellow was perhaps twenty years old, half my age at that time. The garage is no longer in business.

I was reminded of the incident today as I was scrubbing a new set of forged Mahle pistons destined for Bob Polys’ engine. The pistons and other parts are going to the balancing shop tomorrow and it’s important that every trace of the heavy preservative be removed. And there was a lot of it, more than the usual amount. It looked as if one of the pistons had been dipped in the stuff. A mere rinse in the solvent tank didn’t begin to remove the gummy tan grease, it took a lot of scrubbing with a fiber-bristled brush and running a bore brush through the oil scraper holes before it came clean.

Free of the heavy grease and blown dry with compressed air, the gram-scale showed only a few tenths difference across the set of four pistons, close enough for a regular repair. But the two-liter Polys engine will spend much of its life above five thousand rpm so the pistons will be matched to a tenth of a gram. A tenth of a gram of aluminum, not grease.

Had the pistons not been cleaned, the heat of running and the constant spray of oil from the journals would eventually remove the heavy coat of Cosmoline. But in the case of the piston with the blocked oil scraper holes, I doubt if the engine would have broken in properly.

I’ve already posted an article about jugs, explaining the need to scrub the cylinders and paint them, and to clean the pistons and rings, even though the parts are brand new. But having led the horse to water, the rest of the job depends on the horse.

The growing popularity of the Internet is causing many Volkswagen owners who have never heard of the various VW-specific mailing lists to discover the archive of my articles maintained by Richard Kurtz. Sometimes they’re happy with what they find. And sometimes they are not.

Recently, a fellow purporting to be a mechanic happened across the archive and took me to task over the ‘Jugs’ article saying many of the same things I heard from that other fellow twenty years ago. (This fellow referred to my continual emphasis on attention to detail as ‘anal retentive’ which shows he knows even less about psychology in general and the theories of Sigmund Freud in particular than he does about auto mechanics.)

This fellow’s main complaint seemed to be that he had not seen any of my suggestions in the magazines or manuals. I’ve no idea what manuals he’s been reading but when it comes to ‘magazines’ I can make a pretty good guess.

My response was to direct him toward a source providing the same information. Although I couldn’t find a reference to painting cylinders in Tom Wilson’s excellent “How to Rebuild Your Volkswagen Air-Cooled Engine,” I notice the engine pictured on the cover of the book has painted cylinders. And on page 132 under the heading ‘Clean Parts’ Mr. Wilson says what all competent mechanics say -- scrub the jugs. “Such parts are shipped with dirt-collecting grease and oil, and are never cleaned at the factory with engine assembly in mind. That is your job.”

Sermonette

Free advice being worth exactly what you pay for it, when it comes to overhauling Volkswagen engines if you’ve never done one the wiser course is to seek the widest possible range of opinions. And when someone offers an opinion, they should be willing to support it in the form of additional references and so forth. A few questions will be enough for you to tell if the person’s opinion is based on factual experience or second-hand information, perhaps gleaned from one of the VW-specific magazines, whose primary business is selling magazines rather than overhauling engines.

Automotive engineering is a mature technology with a relatively narrow range of acceptable procedures for doing any given job. As you gather opinions on how best to do something you will see that experienced mechanics and engineers tend to do a given task in one particular way and will offer a sound, well-reasoned justification for their chosen method. These are people who know their business. No one can properly teach a subject they have not mastered themselves.

In that regard I think it best to use magazine articles only for their illustrations and to discount their textual content unless it can be verified by other, non-magazine related sources. Because when it comes to engine overhauls, magazine writers and editors can surely teach us all a great deal about selling magazines.

When you overhaul an engine you are the Mechanic in Charge; the success of the job is up to you. You may be a programmer, farmer or accountant but for the duration of the job you are in the Engine Overhaul Business. And it always pays to mind your own business.

- Robert S. Hoover (1995)

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