[Healeys] playing detective

[Michael Salter]

Hi James,
As you have probably concluded "something just does not add up here". If the
piston seal, valve seal and gasket are all good there is no where else for
the compression to leak. 
I would have to agree with the others that the issue has to be valves. If
you are using bronze guides, and you have run the engine I would recommend
that you read this. http://www.netbug.net/blogmichael/?p=384
I have some questions,
1. Did the engine actually run after assembly and before you did the
compression test?
2. Did you actually check for valve clearance at the same time that you did
the compression test?
3. Are you absolutely sure that there was not something inside the ports of
#1 cylinder.
I had a similar issue on a TR6 many years ago when a nut had made its way
into the intake. Sometimes it would just hold the valve open others it would
allow it to close. It wasn't small enough to go through the valve opening
and it fell out of the port as the head was being turned on its side after
removal. Of course nobody had any idea where the nut had come from!!!

Michael Salter
100S (1955)
3000 Mk111(1965)
100 (1953)
AHX12 (1953)
Bugeye (1961)
http://www.netbug.net/blogmichael/
-----Original Message-----
From: healeys-bounces+msalter=precisionsportscar.com at autox.team.net
[mailto:healeys-bounces+msalter=precisionsportscar.com at autox.team.net] On
Behalf Of James Shope
Sent: September 27, 2007 11:15 PM
To: healeys
Subject: [Healeys] playing detective

my friends bj8 started running rough a while back. we were going to do a
tuneup but a compression check showed only 60 psi in #6.  machine shop found
a
crack and pinned it, plus all new valves, hardened seats, and new guides.
new
rings and bearing were also put in.  after reassembly, all cylinders but #1
had 125-130 psi.  1 had no compression. after checking everything we could,
off came the head again.  nothing is wrong!!  the valves look perfect and
held
solvent for over an hour with nothing coming out of the ports.  the cylinder
held solvent until we wiped it out.  the gasket looks perfect.  we took
valves
out and checked them and they appear absolutely perfect.  what else can it
be.
#1 was fine before going to shop and appears perfect now.  anyone ever had
anything like this happen?  now is your chance to be a columbo or dirty
harry.
do your duty and send a clue.   healeymanjim