Ned,
The theory of the "wet" compression test is that a dollop of oil will
improve the seal of bad rings. If the compression goes up noticeably and
temporarily when oil is added rings are the likely cause.
If the valve train looks to be in good condition and you can hear a ticking
noise when U crank the engine over I'm afraid that piston damage is the most
likely problem in which case the ticking will be louder with that plug
removed, particularly if you listen close to the plug hole with a piece of
hose.
It is unlikely that a valve could cause a partial loss of compression and
produce a ticking noise.
The ideal tool to use for diagnosis is a borescope, but not everyone has one
in their tool box.
U can see one here
http://cgi.ebay.com/ebaymotors/New-Borescope-Fiberoptic-Inspection-Tool-18-w
ith-Case_W0QQcmdZViewItemQQcategoryZ43989QQitemZ4629754717QQrdZ1
The first step of repair is to remove the head; it may be possible to change
the piston without removing the engine, but unfortunately bore damage is
quite likely ....sorry.
Keep us posted.
Michael Salter
www.precisionsportscar.com
-----Original Message-----
From: owner-healeys@autox.team.net [mailto:owner-healeys@autox.team.net] On
Behalf Of Ned Smith
Sent: Wednesday, April 12, 2006 10:16 AM
To: Austin-Healey List
Subject: Bad Sound 2
A compression test showed this:
1 - 70#
2 - 150
3 - 155
4 - 155
5 - 150
6 - 170
Clearly Cyl. 1 has a problem.
I am looking at references to a "wet test" and not understanding the
explanations.
If I add oil to the cylinder and compression goes up, this means I have good
rings and valves?
If it does not change, it means I have bad rings and/or bad valves.
Since I can hear can hear a loud ticking when I spin the engine with not
spark plugs, it probably means I have a bad valve?
If so, what then? I guess the head has to come off. Does anyone have a
procedure for doing that?
What other things should be done at the same time?
TIA
Ned Smith
BJ8
near Chattanooga, TN
N34.98 W85.5
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