Great, that means you are closer to the resolution. With regard to cleanup I
would definitely use engine flush fluid (the type that is sold at Walmart
(big 1L bottle). You want to thin the sludge and drain all crap thoroughly,
so all the oil changes should be preceded with this step until the oil is
clear. No particular source recommends that but this is my way of thinking
(after seeing what I have drained first time).


Terry Haywood wrote in message
...

Removed the intake manifold yesterday. It appears to have 3 cracks
running lengthwise. I say "appears" because they are not as obvious as
I expected; I thought I would see a gaping hole with daylight shining
through. I even filled the manifold with water expecting it to flow
out the cracks. It didn't. However there is clear water in the lifter
valley and along with everything else that has been said I'll believe
the manifold is the cause.

My local boat dealer said these can't be repaired. It looks like an
easy weld to me (but I don't weld so I don't know). Do they crack
internally also? What's the problem with fixing it?

Cleanup: Assuming all is well after replacing the manifold I figure
run the engine a few minutes, change oil and filter, run up to
operating temperature, change oil/filter again. Maybe change the
filter again after the first outing. I really don't know, just seems
like I need to get all that water out of there.

After preparing myself for a multi-thousand dollar cracked block
repair I'm practically giddy about dropping "only" $350 for a manifold
and gasket. Hope that's all there is.

Thanks to all for the help,

Terry

On Sat, 08 May 2004 22:32:52 GMT, "Billgran"
wrote:


Terry Haywood wrote in message
.. .
On Sat, 08 May 2004 19:19:59 GMT, "Lawrence James"
wrote:


Yes, I removed those drain plugs from both sides of the block and left
them out. Also drained the exhaust things and pulled off the cooling
water hoses from the water pump.

It's the same thing I have done for the past few years, don't know
what is different. Agree it sounds like a cracked block.




Just above the circulation pump, on the front of the intake manifold,
there
is a pipe plug that has to be removed to drain trapped water on late
model
4.3L engines. Was this done? Many mechanics are not aware of this drain
if
they have not attended a training seminar or a factory school concerning
this engine.

The bottom of the intake manifold cracks from the freezing water and when
you fire it up the following spring, cooling water flows thru the crack
and
right into the lifter valley, and down to the oil pan. Your best bet is
to
pull the manifold and that way you can check for cracks in it and also
inspect the lifter valley walls for freeze cracks.

Bill Grannis
service manager