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I have completed a cylinder head swap with reground cams on a 92 Mazda Protege. All new valve train, new head gasket set, timing belt, and head bolts. I have the car timed properly according to the repair manual. I even had my work double checked by another mechanic! And I still have zero compression in the numbers one and two cylinders. Firing order is right, good fuel, good spark, YET no compression.

Let start by doing the following: 1) Remove the valve cover. 2) Put the cylinders that have no compression up to the top of their compression stoke. (one cylinder at a time) 3) Make sure the cam lobes on that cylinder you are checking are pointing down 4) Make sure the rockers have a little play about 12 thousand of an inch. 5) Attach a compressed air line to the spark plug hole. 6) If the piston does not go down listen for air to come out the intake valve or the exhaust valve. If so, then you MAY have bent the valves when you placed the cylinder head on the engine block.


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