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Opinions on engine problem

To: <6pack@autox.team.net>, <Fot@autox.team.net>
Subject: Opinions on engine problem
From: "Chuck Arnold" <chuck.arnold@oracle.com>
Date: Sun, 21 Mar 2004 10:58:11 -0800
Hi, need some insight on what might be going on with my engine
Facts:
New rebuild, just started
New crank [nitritded]
+4 forged pistons [new]
New rod and crank bearings
Deck blocked
New cam, lifters and moly push rods
External oil feed to number one cylinder.  This originates from a 1/2 NPT
fitting hole made where the aluminum plug was just above the oil filter
housing.  There is a "T" with one side feeding number one via AN4 line, the
other side goes via 10AN to an accusump
Head is unchanged from last rebuild [ported, roller rockers, shaved to 3.3
inches.

I started it yesterday for the first time and let it run 5 minutes to break in
the cam.  Seemed to go OK, but was quite noisy [piston slap?].  At next start
there was an obvious problem that turned out to be two pushrods were loose
[out of their sockets].  Neither was bent.  Both nuts had loosened allowing
the set screw to back off.  Fixed that.
Today I took it for a drive.  Seemed to be OK, ran up to 4K just fine.  Went
up a hill just in case had problems.  At about 2 minutes into the run, a
horrible racket came from the engine.  [hard to describe, obvious metal on
metal that should not have been].  ?Stabbed the clutch, killed the engine,
tuned around and coated to a parking lot.  Rechecked the pushrods.  All was
fine.  Started up again, no horrible racket.  Continued on , and, at about 2
minutes, got the noise again.  Shut it off, rechecked, all seemed fine.
Coasted down the hill.  Restarted, sounded OK, drove back up the hill, same
result, 2 minutes, bad noise.

So, what can it be?  Heat related?  The mechanic, when he decked the block,
said the pistons were not square to the top [uphill to the front] and that he
had to do some adjusting [not sure to what, wrist pins?] to get them lined up
right.

I figure no matter what, the head comes off so I can verify it is not valve
problems, then probably engine out again.  Guess I should pull the oil pan and
see what I can see by looking at the bottom end.

Would appreciate any opinions.


Chuck Arnold
Technical Manager
Oracle Northwest Fulfillment Practice
425 241 0457 [cell]





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