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This is a scan of an article that originally appeared in Car Craft in
September 1998. It is very informative, and deserves to be shared with the
world. If you don't subscribe to Car Craft already, reading this should be
incentive enough to go do it - now. Their
articles and tech sections kick ass and they understand the whole "performance
on a budget" thing better than any other car magazine out there.
(Page 1)
(Page 2)
(Page3)
(My vote for the best item is the one of the hashed short block assembly on
the bottom left of page 2. :-)
I've also collected a few pictures of failures in stuff I've owned or worked
on.
This is what happens to a slant six rod after the engine is severely
neglected for, oh, saw, 30+ years. Eventually the rod bearings wear out and
seize up, then spin, then all sorts of bad stuff happens in rapid
succession. This is from the rearmost cylinder. Note that the rod is bent in
two different planes (aka, it's twisted two different ways), hit the piston
skirt, and broke off completely at the big end (!). Once the big end came
free, it also punched a hole in the side of the block. Sadly, I didn't take
any pics of the window in the block.
This is the oil pump drive rod out of a 1979 Ford 302. It was a "Shuck's
Special" rebuild long block and ran OK for about a decade. One day there was
a snap and then no oil pressure. The cause was this. Note the twisting in
the rod - it was being torqued slowly until it finally gave up and snapped.
Why'd it get like this? The oil pump used in the rebuilt engine was a
cheap-o unit and had a sticky spot in the gears. My best guess is that the
sticky spot caused a high torque to be placed on the oil pump drive rod once
a rotation. Eventually, it couldn't stand the strain and started to twist
along it's length to absorb the strain. Once it twisted enough, it was all
over. When I tore down the engine, the oil pump had finally seized and
wouldn't move. Once I took it apart, it started to move again, but had one
sticky spot in the gears that I could barely turn by hand, even with the
pump cover off. You'd think that because the pump gears are always bathed in
oil, there'd be no problems. You'd be wrong. Luckily, the motor wasn't run
long after oil pressure went away, so it's a rebuildable core. All this
because someone wanted to save $10 on the oil pump when rebuilding the
motor. Any guesses on why I rebuild my own motors and don't go with the
super-cheap-o rebuild special at the auto parts store? This is one good
reason why.
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