Symptoms:
-Tons of black smoke coming from the exhaust. Wideband readings extremely rich. Got progressively worse over starting the car about 6 times. Got to the point where the car would start but wouldn't stay on.
-Compression test was 30psi on all cylinders
-Erratic oil pressure

Problem:
Only a compression test was done. Pistons were assumed to be bad so motor was torn done. It is now in pieces so no further tests can be done.

Teardown Findings:
-#1 and #5 main bearings were damaged
-Pistons and rings look just fine. The rings don't stick. The ringlands are collapsed. Nothing.

Help:
What is wrong with my motor? Can I contribute the erratic oil pressure to the main bearings? What about the black smoke/rich condition?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dominate9 &raquo;</TD></TR><TR><TD CLASS="quote">-Compression test was 30psi on all cylinders</TD></TR></TABLE>

I would have stopped right there. Something is seriously wrong. Valves?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dpaton &raquo;</TD></TR><TR><TD CLASS="quote">

I would have stopped right there. Something is seriously wrong. Valves?</TD></TR></TABLE>

I changed my valves seals on it about a month before it happened. It also came to mind that the valve seals might be the culprit.

 

Valve seals will not effect a compression or leakdown test.Check for bent valves.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by NJIN BUILDR &raquo;</TD></TR><TR><TD CLASS="quote">Valve seals will not effect a compression or leakdown test.Check for bent valves.</TD></TR></TABLE>

Is that something that I can check on my own or do I need to bring the head to a machine shop?

 

So the problem got progressively worse everything I cranked the car. If the valves were bent, wouldn't I get the same response ever time I cranked the car?

Another theory that was brought to my attention was cam timing. Its hard to believe for me personally, but maybe the timing belt slipped. And then slipped again causing the engine to be way off timing which made the car day after a while.

 

You can do a quick check by flipping the head upside down with the cams out and the sparkplugs in.Pour some windshield washer fluid in the chamber and see if it leaks past the valves.
A slipping timing belt could do what you described also.

 

did you ever put a little pit of oil in your cylinders and cranked it again. Also did you remember to have it WOT? That would of told you if you rings were bad or not and would give you accurate readings

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by integ401 &raquo;</TD></TR><TR><TD CLASS="quote">did you ever put a little pit of oil in your cylinders and cranked it again. Also did you remember to have it WOT? That would of told you if you rings were bad or not and would give you accurate readings</TD></TR></TABLE>

With only 30 psi per cylinder there is something major wrong.Most likely bent valves or cam timing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by integ401 &raquo;</TD></TR><TR><TD CLASS="quote">did you ever put a little pit of oil in your cylinders and cranked it again. Also did you remember to have it WOT? That would of told you if you rings were bad or not and would give you accurate readings</TD></TR></TABLE>

Nope, I didn't do the oil trick but like the said, the rings are in great condition...visually.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dominate9 &raquo;</TD></TR><TR><TD CLASS="quote">Symptoms:
-Compression test was 30psi on all cylinders</TD></TR></TABLE>
wow.. that's pretty bad... something is very wrong....