Well, I need to ASK a question this time...
The 1990 6-bolt 4G63T in my Summit GTX has done about 200,000 km, and under acceleration blows quite a bit of oil smoke, meaning the rings are shot. Needs valve stem seals too. Oil was pretty low, just on the bottom of the dip stick, meaning there was about 1L left ie not run dry. I've had it that low before.
Last night it was running fine, but this morning the engine rattled when I tried to start.
Pulled off the rocker cover, and found one inlet lifter (the noisy one) was not pumped up at all and the rocker was floating about under the cam. Put in a good spare lifter, and the rocker was again tight on the cam.
Topped up the oil, tried to start, and got lots of valve clatter, the engine ran like the timing was way off. There was no audible big end knock. Valve clatter suggests no or little oil pressure is getting to the lifters. The standard (Eclipse) oil pressure gauge shows normal.
Disabling the fuel and the starter spins the engine OK, no valve rattling or knocking noises.
The cam timing SEEMS to be about right in that the pulley TDC mark and the cam sprocket marks seem to line up on the right places. This suggests that the hydraulic tensioner has not caused a cam timing problem.
With the plugs out, I can turn the main pulley with an 8" ratchet arm, till it gets to a point that I just can't move it. Surely the valves springs are not that tough? The starter spins the engine over smoothly, no audible "hard" spots that would suggest a really jammed big end.
I know I have to take the sump off and have a look ($sob), and I was planning full rebuild anyway.
What's the consensus? Spun bearing?
Stewart DIBBS