Rocky,
My machinists says it's a fairly easy repair. He drills a hole and puts a plug
in then makes a chain if the crack is bigger then the one drill hole. I saw the
cracks and they are about 1 to 3 inches long. They start at the top of the head
above number 1, 3 and 4 spark plug holes and travel down towards the spark
plugs on the outside as well as on the inside. Number 3 is only just starting
about 1" long. No water areas are affected. I'm going to find another head just
to be safe and check it. If the same symptoms show up, then I'll have to go
ahead with the repair. It cost 50.00 per inch to repair.
Rocky Frisco <rock@rocky-frisco.com> wrote:
JAMES SCHULTE wrote:
> Listers, I talked with my machinists today about my 69C Head. He said
> there are 3 cracks just above where the spark plugs screw into the
> head. He said they are not a problem and he could repair them. If I
> didn't have them repaired, the head might leak oil from these areas.
> Anyone have experience with this sort of thing? Jim 69C 70B
That's when I buy a new head. Seriously.
The only valid way I know to repair that kind of crack includes heating
it up, taking two or three days to do it slowly, until it is glowing
bright red hot, almost melted, and then welding it, using metallurgy
techniques almost entirely outside my reckoning, and then taking another
three or four days to allow it to cool slowly. I would guess a repair
like that would cost five to ten times as much as replacing the head
with an uncracked used one. Anything less than the above-described
process is not to be depended on.
Don't make my mistake and depend on the eBay seller's assurances that
the head isn't cracked; the one I bought *wasn't* cracked, but it *had*
been decked .030" so I burned the top out of #3 piston. After reviewing
the facts, I am proud that I managed 250 miles of highway driving before
it burned out. ;)
>From now on, I will have the shop measure the combustion chamber in the
head, if it's a strange one. The extra $25 is well worth it.
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