I have had a number of listers ask me how my V8 is doing
lately, so I thought I would send this out to everyone. This all took
place in August on the way from Denver to Grand Rapids for the V8
meet; this was also the first part of a horrific move from Boulder, CO
to Akron, OH that ended up involving a new (used) truck, a u-haul, two
trailers, two dead cars in Nebraska, two weeks, and three laps across
the country. Nuff said. Enjoy!!
Here are the details of my engine failure. Unfortunately, my hopes of
a recoverable situation were thuroughly dashed. The engine was
balanced as evidenced from the markings of 1-4 L and R on each rod and
piston. The rods are of H beam type and clearly showed that they were
ground to debur them. It was the #3 rod that broke, the small end was
still in the piston, and I know this to be the source of the failure
because one peice of the H that was left exposed by the failure was
the same darkened color as the whole inside of the block (almost
black). So I know that the rod was cracked for a very long time, if
not from the factory. The engine had 1100 miles on it since the
rebuild from the PO. The rod snapped at the top of its stroke, because
there was no indication of impact damage to the bottom of the piston
which was sitting at the top of the bore. About 1/3 of the skirt was
missing from the #3 piston, including half of the wrist pin bearing
surface on one side. Either the rod broke and the action caused the
fracture of the piston, or the piston broke, cocked in the bore and
caused the rod to break. I think it was the first one because there
was no damage to the #3 sleeve. The rod removed a chunk of the block,
on the passenger side, under the engine mount of about 25 square
inches, gutted the pan on that side,crushed and tore the motor mount
(stock olds mount), and opened up the galley from pickup to oil pump
and broke open the waterjacket; on the other side it punched straight
through the block about 5 times and punced straight through the pan
about 8 times. The #3 rod swung through the #4 sleeve about two inches
up, and cracked and holed the piston on both sides, in line with the
damage to the sleeve. It also hit the cam; the cam broke between the
#2 intake lobe and the 2nd bearing, this first section consisting of
the front of the cam and the first 4 lobes walked out, the timing
chain started to eat the cam gear and all four spokes of the cam gear
cracked. The second bearing and the next two lobes (#3,4 int) broke
and were forced up in the journal about 40 degrees, the #4 int lobe
was the only one showing significant damage, was in line with the
broken rod, and was forced up tells me that this was the point of
impact. The #3 rod was curved about 30 deg presumably from this
impact. The next two lobes, for #3,4 exh, were in the pan, however the
big end cap of the #4 rod showd significant signs of damage from
impacting this. It bent the bolt hole around one of the rod bolts and
I had to hammer the rod apart from this damage, the crank shows a few
small dings from the same impact, the remainder of the cam, from the
3rd bearing back (4cyls worth) was intact. What I think happened was
that the #3 rod hit the cam made the rear most break (at 3rd bearing)
which left a bent cam connected to the timing gear. The bent, spinning
cam then impacted the #4 rod cap causing the other fractures, forced
the cam to angle up, cracked the timing gear, and broke out the lifter
guides for the #3 int and exh and the #4 exh. One of those pushrods
was severely bent, but I found them all in the pan so I don't know
which one. In total about half of the pushrods were bent. The #4 exh
rocker broke where the valve arm joins the rockershaft bearing
surface. I think that when all of this happened the #7 intake was open
and the valve colided with the piston, because this was the worst bent
rod of all, I think this is what caused the back half of the cam to
stop turning. I saw indications that most of the valves had collided
with the pistons, and roughly 10 of the valves were bent, but none
very bad; none of it was bad enough to damage the piston tops but it
did in most of the valves. One of the lifters from the #3/4 area was
shattered and about 1/3 of them were chipped around thier cam
surface. Most of the valve train and block parts were found in the oil
pan, along with the remains of the coolant and the oil. I also found
some magnetic parts that were probably from the #3 rod, since about
1/2 inch of it is unacounted for. The bearings from #3/4 big ends look
perfect as does the rest of the bottom end except #3 and #4's
parts. That leaves me in need of an entire engine as even the heads
are suspect if enough force made it up there to break a rocker arm and
bend most of the valves. The valley pan gasket was severly dented up
around #3/4 but the intake showed no signs of being hit. Basically I
think my only useable parts are the flywheel, pulleys, front cover,
intake, exhaust, and valve covers. Somewhere in here should be
factored in that the right bank showed the most severe signs of valve
/ piston collisions and had a head gasket (steel shim type) .020
thick. The left bank had two new felpro gaskets (steel shim type)
stuck together for a total of .035; and a stock steel shim thickness
of .040. I also noted that the seat and installed heights of the
valve springs were all over the map, well over .050 variation between
them. There also seemed to be a big variation in the installed height
of the valves, but I didn't measure that. Oh well. AND THE MORAL OF
THE STORY IS.... you really ought to magniflux old parts, especially
if you are going to try and lighten a stock part. It looks like the
rod was cracked from new but the fact that they had all been ground
may or may not have been a factor in causing it to let
go. Unfortunately the motor was built about a dozen years ago, buy a
guy that was into these motors in northeast OH. My dad traded him an
old Oliver tractor for the motor and trans, so no chance of
reimbursement or anything there. Whew!!! I think that about covers it.
James Nazarian
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