So many possibilities it's impossible to guess. You'll certainly know when
you get it apart.
-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net] On Behalf
Of Chuck Arnold
Sent: Sunday, March 21, 2004 10:58 AM
To: 6pack@autox.team.net; Fot@autox.team.net
Subject: Opinions on engine problem
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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