Lew,
I don't know about utter despair just yet.
First of all, the cardinal rule I've heard over and over is that your
average compression gauges are reasonably precise but notoriously
inaccurate (an instrumentation problem that isn't restricted to
compression gauges, by the way). So don't worry about exact readings,
just whether they are within 10 or 20 psi (dry) of each other, which
these readings are. I also think that the most that your oil squirt
test has revealed is that #1cylinder has rings that are slightly worn
compared to the others. Not recalling a rule of thumb for wet readings,
they look OK to me. I would certainly recheck dry and wet compression
at every oil change, but I don't think that a 9 psi difference in one
cyclinder is reason for more than mild paranoia.
The plug conditions confuse me. If 1 and 4 are truely sooty (matte
black), then they those cylinders are running rich. But how could that
be if the middle cylinders are at the correct mixture? If #1 is oily
rather than matte, you may well have bad rings there.
How many miles on the engine? Oil and filter changes done regularly?
Ther are other places to squirt oil from: pushrod inspection ports, oil
pan, timing cover, valve cover, rear main seal, sometimes even the
head-block interface. If you haven't already, best to look at them,
maybe after degreasing the engine so the flow is more visible.
Lastly, I would see what the repairs you've just made do to fix the
problem. I would think one could lose oil at a significant rate from
the oil cooler region since it is pressurized - you may well have fixed
your main leak already.
Sorry to be so long-winded.
Geoff Cram
66B
gcram@wdni.com
----------
From: Lewis Dove
To: mgs@autox.team.net
Subject: engine compression
Date: Tuesday, October 01, 1996 10:25AM
>> Now for something new: I am planning a 3000+ mile trip later this month
and have been having really bad oil loss problems. I found a leak in the
oil hoses and replaced them along with the oil cooler. I still
lose/consume oil, so I checked the engine compression, warming the<<
etc...
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