Chuck:
Just my 0.02 worth:
Sounds like piston to valve contact, or possibly piston to head
or
valve spring coil bind.
The loosened pushrods are a clue.
The fact that you have installed a new cam, and decked the block
(instead of blocking the deck?) has removed piston to valve clearance.
You don't say what you new cam's specs are, nor do you mention what your
roller rocker ratio is. You have shaved the head, which also removes
valve/piston clearance. All of these are important details, given that
you have extensively modified your motor.
So,
1. Check for valve spring coil bind.
2. Check piston to valve clearance.
3. Check piston to head clearance.
Just curious; what ratio rockers are you running, and
what are your cam specs?
Vance
-----Original Message-----
From: owner-6pack@autox.team.net [mailto:owner-6pack@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.
<snip>
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
|