Ok, pretty sure my problem was a blown head gasket. Pulled the head and the
gasket seems to indicate that that is the case, but I don't have a lot of
experience reading signs. Nice clean copper color except between #2 and #3
and between #4 and #5. There, the gasket was a dark brown/black color,
which I would guess would indicate something was happening there, that
wasn't occuring elsewhere, ie. maybe either combustion gases causing the
darker color, or possibly water stains? I'll be taking the gasket with me
tomorrow to the machine shop when I take the head to have it magnafluxed and
checked for flatness, and have them see if they can read the gasket to tell
me what might have been happening. Not really any signs that water was
getting into the chambers, as al cylinders had about the same amount of
carbon buildup...so I suspect, the problem was the combustion gases getting
into the water jacket. I finally saw the bubbles (lots) in the rad. When
the radiator is very full, you don't see them...but if the level is down
about 1/2 - 1 inch, they are very apparent. I guess I would simply have
been checking with the rad topped off.
However, I think I need some suggestions on the best way to replace the new
head gasket. That head is very heavy, and since there are no alignment pins
to hold the gasket in place while I try to manuever the head onto the block,
does anyone have any useful suggestions on the best way to try this with the
engine in the truck...last time I did this, the engine was out...much
easier. I think I may try to position my body in the engine compartment in
order to be able to lift the head onto the block. Very difficult to do from
outside the fender (too heavy to hold the head with arms outstretched, and
not really very easy to position two people on opposite sides. Just getting
the head off was difficult...and that was when it really didn't matter if
the head gasket was maybe scratched or slightly damaged in the process. The
reverse will need to NOT damage the head gasket in any way, so if anyone has
tried this with the engine in the truck, please let me know how you did it.
Oh, one more item. When I removed the head bolts, I was very surprised that
it took very little force to loosen them...seems it should have been
somewhat difficult, right? I know I never retorqued them after the first
500 or so miles as I was not aware at the time I rebuilt the engine that I
should have done that, and then just never did as everything seemed to be
fine until just recently. Obviously, if they were a bit on the loose side,
that certainly would have helped to lead to a blown head gasket. So, what
I'm wondering, is the force needed to loosen them not necessarily gonna be
all that much? I will be chasing all the threads, both in the block, and of
the head bolts.
Is it possible to still get replacement head bolts from a FLAP? I almost
torqued a head off one the last time I did this, and don't want to risk that
again if I can help it. How safe is it generally to reuse head bolts?
Finally, I believe that only the number 1 bolt enters the water jacket...is
that correct? (By #1, I'm referring to the center bolt, nearest the outside
(passenger side of the block). So, if correct, then that is the only one I
would need to put a dab of RTV on the threads, right?
TIA,
Rob
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