No compression after new timing set, tensioner and head
I have a 2004 Pontiac sunfire, the timing chain tensioner went bad, bent all valves on exhaust side. The mechanic replaced: Timing Set and tensioner, Head, all gaskets and head bolts. Car was put back together. The car cranked up and ran for approximately 10 mins. There a metallic pop and the engine shut down and will not crank back. Now no cylinders have compression. When engine is rotated cams and valves operate smoothly, mechanic checked cam timing and said it was good. No strange noises when the engine is turned over by hand or with the starter it just does not have any compression. Do you have any ideas as to how it can go from running with good compression to not running with no compression?
head gasket or rings, I'd guess head gasket (I'm assuming no cylinder has compression) Have your tech check the seating surfaces and torque values for the head bolts.
Head gasket is new of course, the head was resurfaced and the bolts were torqued to the manufactures specs, new head bolts were aslo used because this engine uses stretch bolts for the head. It had compression before the metallic pop and it quit running. It seems rather unlikely that all the rings would have failed at the same time. Is there any kind of pressure release valve for this engine?
did you ever resolve this?
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