Hydraulic Valve Adjuster

[Charlie Guthrie]

Problem resolved. Thanks for the helpful responses. We received several good
tips and specific instructions which gave us confidence to proceed. And now
the rest of the story:
The noise started at an autocross on Sunday afternoon, but it didn't sound
terrible. The sound was not the ticking sound that one usually associates
with sticky valves or excess valve lash; it sounded more like a knock (small
ballpeen hammer tapping inside the valve cover). We were, however, convinced
that the sound was coming from the top of the engine, so it MUST be
valves....right.
Getting the valve cover off was straight forward enough (if you discount the
time spent crawling around under the car in the dark looking for the dropped
nuts and washers from the cover, and the impossible to reach bolt that was
dropped into the crack between the header pipes....we did eventually find
the bolt). Sounds like a comedy of errors so far.....but wait, there's more.
With the cover off, we could see no evidence of broken parts or hydraulic
adjusters that were stuck,  all the adjusters were nice and springy.
Refusing to put the cover back on until we had found the source of the
noise, I stood over the engine to listen and look for unusual behavior while
my son, Pete, started the engine. With the emissions hoses off, the idle
speed was around 2K RPM. It is truly amazing how much oil is slung around
inside the valve cover (when it's on), my left side is now completely
saturated in 10W30 synthetic, and still no clue what is making the noise.
Not to let the evening go to waste, Pete decides that we should replace the
timing chain tensioner with the new one that was installed in the previous
engine just before it blew up. I insist that we at least put the engine back
together before we start the second phase. Being older and grouchier, I win.
Pete handled the hard parts of bolting things back together and I performed
the highly technical task of plugging in the plug wires....let's see,
4...3....2....Hmmm....2....that feels funny, must have bent the connector
because the boot won't seat on the valve cover. Try the #1 plug boot on the
#2 plug......HHHMmmm. Neither of the boots will seat all the way down.
Better pull the plug and see what is bent. Slip on the plug socket and break
the plug loose.......HHHHMMMmmmmmm! Pretty easy to turn.....only 2-3 turns
to remove the plug. The plug had loosened and was backed out almost 1/4"
(6.35mm).
Tightened the plug, fired it up......TaDa! noise all gone.
I have been working on cars for a very long time and have never run across a
loose spark plug. I would have never guessed that it would sound like that.
Interestingly, Pete had not noticed a significant loss in power with the
loose plug, but I have to believe that it cost a few horsepower. Maybe he
would have won that autocross if he had all 4 cylinders....he likes to think
that, and maybe he would have....he wasn't running in my class.
Charlie Guthrie
Old age and treachery
always overcomes youth and skill.

Again thanks for being out there when the call for help went out.