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Sunday, March 16, 2014
ENGINE BIRTHS AND BOO-BOOS
Men never get an opportunity to give birth. Never have and never will, But I do
believe that we get to have an experience that's somewhat akin to birthing a
baby. What on earth could that be? Now, I don't want to insult any of you ladies
out there, so please don't take this too seriously! But, I'm referring to giving
birth to an engine.
If you've ever built an engine - assembling it piece by piece, and then cranking
it over, watching it come to life - you know what I mean. First you must spend
countless hours measuring, checking, and determining what's needed to complete
the rebuild. Then you go out and find all the parts you need to complete
the job. Finally, there's the long and laborious assembling of all those pieces.
Everything must be done with extreme care and in a certain order. Certain parts
must be bolted together and then torqued to proper specifications. Gaskets and
seals must be installed in their proper places. The timing gears must be lined
up, and the cam timed properly. And all the parts that are normally lubricated
must be coated with a special grease. That's so they won't starve of oil until
the oil pump is primed and is able to pump oil to all the moving parts.
And then, after all those long painstaking hours of work, the moment of birth
finally comes. You twist the key and bring the engine to life. First, it cranks
and cranks over. It takes its first breath. It starts to fire as it sparks to
life. And the final reward is hearing it roar as it fires up. And everything
that you did, all those painstaking hours of tedious labor, must be right on the
money - or it won't work. Even the tiniest mistake can result in a disaster. But
this is the story of one particular engine rebuild that didn't go well, In fact,
it ended in a disaster.
I've certainly had my share of engine disasters in my time. Ironically, it was
because I didn't want to make a mistake - building this particular engine - that
the disaster happened. I let the machine shop build it for me, and they blew it
royally. And this was an important engine that was going into my personal
vehicle, my Ford camper. Unfortunately for me, my shop at that time was completely
open on one side and sand blew in the door making it impossible to assemble the
engine without grit contamination. So I let the machine shop build it for me.
Actually, I had the machine shop assemble the short block and grind the valves.
A "Short block" refers to the block sans the cylinder heads. I installed them
myself. I had the engine fitted with new pistons and a reground crankshaft. It
got a new camshaft, lifter, oil pump, and all bearings. The connecting rods were
reconditioned and the cylinders were bored oversize. The ticket was a couple of
big ones, like two grand plus. But, its the price you must pay for reliability.
After all, I wanted my camper to be as reliable as possible. That's what you pay
for. I mean, I could have just installed a junkyard motor and taken my chances
and saved big bucks. But who wants to break down in the middle of the Painted
Desert, right?
I know, I know. This is supposed to be a story about the joys of building an
engine and watching it come to life for the first time, right? Okay, I really do
love to build engines. Build plenty of 'em. In fact, I once had a job where
that's all I did - build engines day in and day out - engine after engine. I
guess I became somewhat jaded after "birthing" all those engines. After awhile
you get kinda' callused. You stop caring. I mean it works or it don't work -
and you could care less if it don't. Oh yeah, you care enough to be sure that
your productive - but not to the point of being insane about it.
I also remember those engines I installed when I worked at the Mercedes-Benz
dealer in Palo Alto. Hey, that was really a tight-run shop. Clean, clean, clean -
everything had to be as clean as a whistle. You had to keep your clothes neat
and clean. Shoes shined. Hands always clean. Wash your hands maybe twelve times
a day. Because if you didn't, and you left a grease smudge on a customer's car,
you were fired right on the spot. And we didn't build engines either. We only
installed Mercedes-Benz factory-built ones.
Oh, and what a strange sight those engines were, those beautiful Mercedes-Benz
engines sitting there in their cages. That's right, cages. instead of being
shipped in a crate like other rebuilt engines, they came in a cage - just like a
lion. In fact, it looked a lot like a lion cage - with strong metal bars and a
cage door. Only the door was on the top instead of in front. Wild! It was like
the engine was dangerous and had to be kept in a cage or it might get out and
run away!
As part of my initiation at that MBZ dealership, they tested my skills. And no
one warned me about it either. they just sprung it on me. When I came in to work
one Monday, there was one of those engines-in-a-cage sitting on the floor in my
work bay. Next to it, on my rack, a car was waiting to have it installed. By
five o'clock I had the new engine in the car and running. The old engine was
bolted in the lion's cage, waiting to be shipped back to the factory in Germany.
Now that was an accomplishment. There aren't many guys who can swap out an
engine and have it running in an eight-hour day. And remember, when I was done,
there couldn't be as much as one smudge left on the car either.
Then, the next day when I came in, there was another new engine sitting in a
cage, and another car in my bay waiting for a transplant. And once again, by
five o'clock, the new engine was running and the old one was bolted to the cage,
ready to shop, Then, on Wednesday, the same thing. Thursday ditto. And when
Friday came, things were different. This was the final test. Instead of being in
my bay, the car needing an engine was parked on the outside service rack, and
the engine was sitting next to the door. Chan, the shop foreman, had taken over
my rack and was using it for some other job he was involved with while his rack was
tied up. Actually, it was a setup, just so I would have to do the job outside.
It's not like I mind working outside. In fact, I love the opportunity to get out of
the stinking shop and work in the California sunshine. But, it was raining that
day. Bummer. I would have to do the job in the rain. So, I rolled my toolbox as
close to the door as I could, without blocking it, and went to work. Working in
the rain means slipping on the pavement, having tools slip out of your hands,
and rain trickling down your back while you worked. But, by 5 o'clock, that
engine was installed and running. I had passed the test. My initiation was over.
I'm sorry. I've strayed from the story. I was telling you about the Ford engine
in my camper, Anyway, as I was saying, I had this machine shop build the engine
for me because of the sand that would blow into my shop. I installed the engine
in my camper and went happily sailing around the country. Over the next dozen or
so years, I drove that camper all over. I visited Yellowstone, Yosemite, the
Grand Canyon, Arches, the Painted Desert, drove the Blue Ridge Parkway and even
the 7-mile bridge to Key West. I took I-10 from Tallahassee to L.A. and went
from San Francisco to Baltimore, and back again, camping all the way. Loved every
moment of it.
It was fifty-seven thousand miles later, and more than a dozen years, when I was
on my way into Denver that it happened. As I drove westbound, halfway across the
great western prairie that leads to Denver, I noticed one of the cylinders
beginning to misfire. How could I tell? After spending that much time in the
driver's seat of my camper, I could tell. I knew that engine intimately. And I
knew instantly, when it began to miss. I stopped and checked all the usual
things, but nothing appeared to be wrong. So, I decided to limp into Denver
where I could do a more thorough analysis of the problem.
The next day I began my diagnostic checking by pulling the spark plugs. Oh how
well I remember the sinking feeling when I removed the spark plug for
number-eight cylinder. It was completely oil-fouled. Not good. I figured that a
valve guide was probably to blame, and calculated that I was in for some repair
work to the head. No big deal. Maybe a few days delay, no more. Boy was I wrong!
I removed the cylinder head and popped off the valve keepers in order to get the
springs off so I could eyeball the guides. There wasn't anything wrong with the
guides. Damn!
With major depression setting in to my mood, I figured it had to be a damaged
piston. Wrong again! As I carefully examined number-eight cylinder, I saw a dent
in the cylinder wall. Not just a nick, but a big dent. I mean big! By now my
heart was in my stomach as the realization hit me. This engine was toast. A oat(?)
anchor. Scrap metal. What caused the Dent? I just had to know, But First, I
would need to find another engine or remain stranded in Denver! Luck was with me
and I located a used engine in a local wrecking yard. Only $350. Guaranteed to
run. Oh goody, I wasn't stranded.
Knowing that another engine was available, I rented a portable engine hoist,
jerked out the engine and began tearing it down in order to find the answer to
the mystery of the dented cylinder wall. I discovered the answer as soon as I
removed number-eight piston. The damn machine shop had failed to install the
piston wrist-pin clip and the wrist pin made the dent. Without the clip, the
wrist pin floated in its bore. And when the circumstances were just right, it
would slide over and kiss the cylinder wall. The dent was exactly at the place
where the piston changed direction from its upward to it downward stroke. When
this happened, coupled with the force of the air-fuel combustion, the piston pin
would shoot sideways and hit the cylinder wall at exactly the spot where the
dent was.
Funny, for years I had been hearing an engine tap or knock. In fact, it began
not long after I installed that engine. it would come an go, sometimes louder
than others. I figured it was a lifter or rocker arm. But since it never got
worse, and the tapping was so intermittent, I would just wait until it failed
altogether before digging into it. i(I) had no idea that I was hearing the wrist
pin banging against the cylinder wall!
I've seen this kind of mistake before, but it always looked different. The usual
scenario when a C-Clip is left out will result in the wrist pin gouging a long
trough in the cylinder wall - the whole length of the piston st(r)oke. but this was
only a dent. It looked like someone had taken a ball-peen hammer and hit the
cylinder wall in the same place a million times. Why wasn't there a long gouge
in my engine's cylinder wall? And why did it take fifty-seven thousand miles to
fail, instead of a couple hundred - as usual? What was different? Was I blessed
or what?
The answer was simple. The difference was that I used synthetic oil. The
synthetic oil was such a terrific lubricant, it prevented the piston pin from
digging into the cylinder wall. When the pin hit the wall, the synthetic oil was
there to lubricate it and keep metal-to-metal combat from taking place. It
provided adequate barrier protection, never allowing the two metals to bind or
scrape. Instead, the pin would just hit, bounce back, and go about its merry
way. And over the past dozen years, and all those miles, the pin had hit the
cylinder wall enough times to make a large enough dent to allow oil to bypass
the rings. And that's what finally fouled the spark plug.
So what was I do to? The machine shop screwed me totally when they built the
engine. What could that machinist have thought when he finished and discovered
the extra wrist-pin clip laying there? Did the jerk even know he'd made a fatal
mistake? Maybe he was on drugs. Was there anything I could do now, a dozen years
later? No way. Sorry. Too bad. You don't just walk in and say, "Hey, you screwed
up an engine rebuilt(d) that you did fourteen years ago and I want my money back!"
I don't think so. There wasn't a damn thing I could do except eat the mistake.
Welcome to the wonderful world of automotive repair. Anyway, I installed the
used engine and drove away with hatred and loathing for that machine shop. For
the previous week I had racked my brain trying to come up with a way to get even
with them for their dirty deed. Now, here I was, driving with a junkyard engine
after all. And all the money I had spent on having the other one built was
wasted.
Just for the record, the junkyard engine only lasted eighteen thousand miles
before it went south. And it was a total mess, needing everything to be rebuilt
or replaced, including a bent crankshaft. And as I went through it, and was
rebuilding the heads - which I had swapped with the junkyard engine - I found
another mistake. The jerk also installed the valve-guides upside-down!
Anyway, with the nightmare behind me, I drove away from Denver en route to Santa
Fe. As the miles disappeared, my anger began to abate. My hatred cooled, and my
thought(s) turned to my vacation once again. As I drove through the day and into
the night, lo and behold, another nightmare started to happen. I began hearing a
horrible noise coming from the driveline. A loud metallic nose, like a metallic
snap. But, that's another story.