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Tom's 392



I finally had a moment to pull the driver's side head from the 392 (that
suddenly lost all compression after 900 miles on #7 after breaking and
bending #1 pushrods) last night.

The head gasket seems to be "OK" to my untrained eye. It tore just a
little when removing the head, and the headgasket and dowels both came off
with the head, leaving just a spot or two near water jackets of torn
gasket.

I haven't pulled the gasket from the head yet. I need to get the digi-cam
and get pictures of what I have thus far.

On the head, the front chamber (#1) looks a little "drier" or cleaner than
#3/5, which look dull and carbon'd, while #7 has a streak of "wet" across
both valves.

It could be coolant from tearing it down, though the stand leans with the
front down. #7 and #3 had coolant in them, with less on #1/#5, but those
were closer to TDC, too.

No obvious signs on the head of the valves hitting anything or being
nicked or anything else.

On to the block.

No obvious (to me) signs of headgasket failure. I'll get pictures.

All 4 pistons are carboned. #1 is at TDC. The other three all have a
black carbon ring about 3/8" thick (going Up/down the bore), and then
another ring, about 3/8", that's discolored ("gold"-ish color), before
going to the rest of the bore, which is roughly uniform.

I see little black lines in this discolored area, that might be carbon
deposits. I see some in each bore I can see. #7 has a couple lines at 6
o'clock, within 1/2" "grouping" - I presume these lines are from the top
ring gap, and it's walked a little. The other bores have a slight
variance in the location of the lines as well.

Nothing looks obviously scratched to me, and there's no hole (visible) in
the #7 piston.

I still need to drain and pull the pan, and then see about pulling the #7
piston out, for a closer inspection.

But thus far nothing LOOKS bad.. at least, not like my spun con-rod did on
my race 304C ("Black.. hmmm..")

-Tom Mandera, Helena MT
'74 200 Travelette, dead "hot" 406cid 392.. just got a 5spd w/ PTO for it
though..


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