I was tinkering with Martha (my '77 Midget) this past weekend, and
encountered something really odd. When I ran a compression test for a
baseline, the results came out:
1: 153 (or thereabouts, my tester's only marked in 5lb increments)
This was done with all sparkplugs out, throttle held open and piston lifted.
Now the car hasn't been running badly (slightly rough idle sometimes, but
nothing objectionable). I checked the valve lash (thinking I had
ham-fisted it the week before), and they were all .010, right where they
I ran a pseudo leakdown test by hooking up the compression tester and
cranking the engine 4-5 revs, left the tester hooked up and noted how much
the pressure dropped off from the max reading in 20 minutes. I only
checked the best and worst cylinders (#4 and #2) as it was getting late,
but they each only bled down about 3 lbs in 20 minutes.
Anybody out there have any ideas of what's going on here?