It sounded like maybe I had blown an exhaust gasket this weekend. So I drove
the 200 miles home, and it didn't seem like a serious problem, but I figured
I'd investigate further before ordering parts. Last night I looked (with no
real sense of urgency) for that leak. With the engine at idle I could not
feel any puffing of hot gases from around the manifold-catalyst joint, but
there could have been a small leak I didn't detect at that level of effort.
(I wasn't ready to burn my hands by feeling around the backside, and it was
late and the car was idling in the garage - not good for breathing.)
What I did notice was a lot of valve clatter. So I went to dinner, then
returned in a few hours to check his valves. They are supposed to be .010
in. One intake valve had opened up to .014 (!), some were nearly right on,
some were slightly tight, especially both on cyl #3. Hmmm, I had set these
valve clearances this spring, not that long ago, but maybe it *is* overdue.
Geez, usually I futz over this car too much, looking for stuff to do that
isn't necessary, so I can't imagine how they got so far off. Well, the
engine had cooled and I had only idled it for a few minutes an hour or two
before, so I set them all. Then I checked compression just for curiosity.
The plugs looked absolutely great, but the compression was curious.
some slop for memory)
Hmmm, #3 looks suspicious. Squirt a little Marvel Mystery Oil in #3 and
try it again. It comes up to about 179, not really much, I figure. Maybe
some of the low compression here is due to valves, some due to rings. But
then, a little oil might bring the others up by 10 psi too. Note too that
#1 is quite high, and it is (coincidentally?) this cylinder that had the
very loose intake valve. Okay, put it all back together, go for a quick
test spin. (Blew one headlight!) The engine still sounds like a sewing
machine, but not quite so much. Maybe I should recheck them tomorrow. There
seems to be a very slight spitting sound, but I can't be sure; certainly it
is not especially louder under load. Maybe there is some crud on a valve seat
that will burn off if I drive with it properly adjusted...wishful thinking.
This morning I drove him to work, and the engine feels just fine. There is
no *noticeable* spitting as from a blown gasket, but there may be a slight,
possibly imagined spitting from something. And there is still more valve
clatter than I would expect, but I can't be sure. By this time my judgement
is becoming suspect. I don't know what I am hearing or imagining. Can't
work on him tonight, the band is practicing. Tomorrow maybe I will check
all those valve clearances when the engine has not been run for a day. I
may re-check compression. I will try harder to locate any exhaust leaks.
What I am afraid of is that somehow in the last two months I may have fried
a valve surface or seat on #3. Another parallel possibility is a damaged
cam surface for one of the other valves. I dunno'. At this point there is
nothing to do but wait, I guess. Eventually I am going to have to do some
heavier work on him, to plug oil leaks at front and rear of the tranny, and
maybe the engine rear seal too. Pulling the head would be easy if I had the
time. And the space. Etc. At this point I am open to comments. Nothing
bugs me more than feeling like that *might* be a problem, but I can't be sure,
let alone identifying it...
Jim Muller
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